An interesting study by Drs Jenny Stauber and Mark Florence from CSIRO’s, Division of Energy Chemistry, Lucas Heights Research Laboratories, Sydney, Australia found that copper ions depressed both cell division and photosynthesis in many species of algae notably the common freshwater green alga, “Chlorella” (Chlorella pyrenoidosa). They suggested that ionic copper toxicity may result from an intracellular reaction in which copper suppressed mitosis. In addition, they said that copper inhibits the enzyme catalase and reduces cell defence mechanisms. Reference: J. Stauber and T. Florence, ‘Mechanism of toxicity of ionic copper and copper complexes to algae’, Marine Biology 94, 511-519 (1987).

●    Liquid seaweed extracts
Scientific opinion on the beneficial effects of seaweed extracts on plants range from dismissal as “muck and magic” to cautious acceptance (Abetz, 1980).  Unscientific opinion is often wildly enthusiastic and claims all sorts of wonderful effects. Liquid seaweed extracts are sold in garden shops under weedy names like Seasol, Marinure, Maxicrop, Algistim. Scientific analysis has shown that the beneficial effects are unlikely to be from the mineral nutrients in the extracts but possibly come from hormones or other organic substances included in the extract. Claims are made that seaweed extracts affect plants in the following ways a) increase frost resistance, b) increase resistance to fungal disease, c) increase resistance to insect attack, d) result in higher yield, e) deeper root penetration, f) increased nutrient uptake, g) better shelf life of fruit and vegetables.  A good EEI might be to investigate these factors, however, it would not be possible for you to investigate a), b) or f) in an acceptable way but other features are open to experimentation.  Alternatively, you might try something new like the effect on keeping qualities of cut flowers. Click Project 2-2 for Prof. Jennifer McComb’s resource sheet.

Marine phytoplankton are extremely tolerant to changes in salinity. The best algae growing conditions for most species is at a salinity level that is slightly lower than that of their native habitat. Salinities of 20-24 g/L have been found to be optimal.	Seasol Liquid seaweed extract. Said to be a “soil revitaliser, growth stimulant and plant tonic, not a fertiliser”.

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●    Life cycle of mosses
Little is known about the relative importance and timing of the parts of the life cycle of most Australian mosses.  The sort of details that are required are the times of spore discharge, growth of the protonema, leafy gametophyte production, sex organ production (archegonia and antheridia), fertilization, growth of sporophyte, relative importance of reproduction by spores or gemmae and tubers. Decide how much time you want to spend in the four possible areas of activity – field observations, spore culture, cultivation of gametophytes, experimental investigation of spore and leafy gametophyte growth. Where are you going to get information on local temperatures, day length, rainfall etc. to relate to your life cycle observations? Click Project 3-1 for Prof. Jennifer McComb’s resource sheet. Note: this EEI does not involve manipulating variables; instead it relies on natural variation.

The upper part of the moss capsule (sporangium) often specialized for gradual spore discharge.	The life cycle of moss begins with asexual reproduction. Leaf-like moss grow thin, brown stalk with capsules at the top. The capsules contain tiny spores instead of sex cells. Spores are the cells that can develop into a new individual without fertilization.	Moss spore capsule. Coloured scanning electron micrograph (SEM) of the mouth of a capsule (spore case) of a moss. Mosses reproduce by means of spores (small blue spheres) which are dispersed from the mouth of the capsule by the numerous rays (orange and brown) that snap open.

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●    Germination and growth of moss spores
It is fairly simple to grow moss spores under sterile conditions.  In time, leafy gametophyte may grow from the protonoma.  You might like to try to grow spores of various Australian mosses about which little is known.  Alternatively, you could pick one that is easy to grow like Funaria hygrometrica (Club Moss) and conduct experiments to determine what controls germination, growth, differentiation of leafy gametophytes etc. An EEI such as this will depend on what time of the year you do it. Mature spore filled capsules are mostly available in the latter half of the year and ones collected in February, March often are hard to sterilize.  Glasshouses may be a source of ‘out of season’ capsules. What will you look for as an early sign of leafy gametophyte development? How might you count the numbers of spores per capsule, per culture, or the number of leafy gametophytes that form? Click Project 3-2 for Prof. Jennifer McComb’s resource sheet.

Funaria hygrometrica (Club Moss)	Funaria hygrometrica (Club Moss) found growing on a fireheap.	Club Moss spore

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●    Bulbs that pull themselves down into the soil
Some plants have contractile roots that pull the bulb down into the soil.  Oxalis (sour sob) does this, but the published work is on American species and it would be of interest to know how the local weed species (Oxalis pes caprae) behaves before designing eradication programmes. This suggests a possible EEI. Are you going to use bulbs of one particular size or compare burial rate/final depth of bulbs of different size classes? How does the final burial depth and switch over from vertical to horizontal contractile roots compare with depth of bulbs in the field? Click Project 4-2 for Prof. Jennifer McComb’s resource sheet.

Oxalis pes-caprae is often called by the common name  soursob due to its pleasant sour flavour.	"Sour sob" is also a local weed - but is quite pretty.	Close up of its roots.

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●    Root responses to gravity
As you know roots grow downwards and if tipped sideways will curve over to point downwards again.  This is called geotropism.  There are lots of fairly conventional experiments you can do to find out which part of the root bends, if bending occurs if the roo tip is cut off, the relationship between the outward force and gravity etc.  However for an EEI you may wish to do something more difficult. It is known that the first root that comes out of a seed (the radicle) is strongly geotropic.  Lateral roots must be less so.  Can you measure the strength of geotropism in a radicle and compare it with that seen in 1^st order, 2^nd order laterals?  Is there any difference between plants that have a taproot compared to a fibrous root system?  If you cut off the tip of the radicle when it is about 2 cm long is the strength of geotropism altered in the side roots if you measure it about a week later? How will you measure curvature? How are you going to measure “strength” of geotropism? How are you going to hold the seedlings vertical till you’re ready to start the experiment? Click Project 4-3 for Prof. Jennifer McComb’s resource sheet.

Example of geotropism in the remains of a cellar of a roman villa in the Archeologic Park in Baia, Italy.	Coloured scanning electron micrograph (SEM) of a late stage in the germination of a plant seed. The radicle (white), the embryonic root, is growing downwards in a response to gravity.

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●    Root parasitism by the Christmas Tree
The West Australian Christmas tree Nuytsia floribunda is a “hemiparasite”.  Although it has green leaves and apparently normal roots it is unable to live unless it makes connections with the roots of other plants from which it sucks nourishment.  The connections are called haustoria and a possible EEI would be to discover what stimulates the Christmas tree roots to make haustoria.  Other hemiparisites are found in Queensland and these may be suitable for this investigation. Trees are apparently not very selective as they have been known to latch hopefully onto underground electric cables. How will you select the place in the field to bury your objects?  How will you find the stuff you bury in several months’ time? Are you going to have one harvest or several? Think carefully about your experimental design so that you will distinguish between substance, shape in cross section and diameter of your test objects. Click Project 4-4 for Prof. Jennifer McComb’s resource sheet.

The species is known locally as the Christmas Tree, displaying bright orange flowers during the Christmas season.	The Western Australian Christmas Tree is an important food source for wallabies and kangaroos. The habit of the species is a tree up to 10 m high, or as a shrub.	Plant roots with attached white Nuytsia haustoria. Photo by Christopher Taylor entomologist.

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 ●    Rooting of cuttings
Propagation of plants from cuttings is important in the horticultural industry and there is a continual search for compounds that will improve the success rate with rooting cuttings.  Auxin hormones which induce root formation are available commercially.  It has been found that commonly used fungicides may have a stimulatory effect or a depressing effect on root production when used along with the rooting powder.  For an EEI you might like to examine the effect of these chemicals on some exotic and native plant species. For interaction experiments like these you have to be extra careful about your design.  There may be several ‘control’ treatments necessary. How are you going to score rooting?  Can you devise a quantitative scheme that will convert observations like ‘poorly rooted’ and ‘many vigorous roots’ to numerical values allowing a mean to be made of all cuttings for one treatment? Click Project 4-5 for Prof. Jennifer McComb’s resource sheet.

Rooting hormone compounds are available  in the form of a dry powder (above) or as a gel or liquid.	Ezi Root Gel is an Australian-made blend of IBA (indole-3-butyric acid) and  NAA (naphthylacetic acid) hormones along with a wetter and fungicide.

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●    Tolerance to waterlogging
Plants vary in their ability to survive periods of waterlogging.  Species differ, and within species some strains or cultivars are superior to others.  Observe which plants have survived in waterlogged areas in your district, and those that are abundant on well drained sites.  You could do an EEI to show whether or not species found in waterlogged conditions can in fact survive waterlogging better than others. At what stage of growth are you going to flood the plants; to what depth? For how long? How are you going to measure recovery, growth, yield and so on.  Remember, a plant has both above and below ground parts. How many harvests are you going to make? What other soil or water parameters might you measure during your experiment? Click Project 4-6 for Prof. Jennifer McComb’s resource sheet.

Olive trees: even small periods of waterlogging or "wet feet" can predispose trees to root-rot and other disorders that affects tree growth and survival.	In high rainfall areas of Australia, waterlogging is the major constraint to soil health and crop yields particularly of many grain legume, oil-seed and cereal crops early in the growing season. Photo: S. E. Victoria.

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●    Effect of seawater and/or detergents on plants
Plants that grow along the beach can tolerate the salty ocean spray that blows onto their leaves.  They may however be severely damaged or killed if any detergent gets into the water.  The question is what would happen to your local beach plants if the sea water was polluted with detergent? The beautiful Norfolk Island Pines around Sydney beaches like Bondi and Maroubra were killed as a result of the detergents in sewerage released in the ocean (see Pitman, MG, Dowden HGM & Humphreys, FR 1977, ‘The outfall connection: the plight of our coastal trees’,  Australian Natural History, vol. 19, no. 3, pp. 74-8). Plants that grow around river estuaries that go salty in summer could also be investigated. Having observed the effects of an experimental salty spray and which plants are most sensitive you might check out plants near your local ocean sewerage outlet.  It is important to know how the sewerage is treated as different treatment methods reduce the amount of detergents that remain. Will you treat the plants with detergent in straight sea water or diluted sea water?  How often will you treat?  How will you mark the treated leaves, prevent spray drift, score the damage? What will be your control? Is there any way of measuring the salt the plants get in the field in addition to your experimental sprays? Click Project 4-7 for Prof. Jennifer McComb’s resource sheet.

Norfolk Island Pines along Bondi Beach, Sydney,  at the southern hill.	Norfolk Island Pines at Port Macquarie, NSW

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●    Effect of coal seam gas water on plants
Coal seam gas is an important energy resource in Queensland and production of this gas now makes up an increasing proportion of Queensland gas demand. Coal seam gas is natural gas - a mixture of predominantly methane and other hydrocarbon gas compounds. It is bonded (through geological and hydrological pressure) to microscopic surfaces (described as cleats or fractures) of the coal. It is effectively held (adsorbed) in the coal by burial pressure and water. Coal seam gas producers drill numerous wells into the coal seams below the surface to extract the gas. The Queensland Government acknowledges that landholders face increasing pressure for access to their land for gas and other resources exploration and development. Water is a primary by-product of CSG development. The quality of the water ranges from potable to saline and may be rich in other constituents that make it unsuitable for many uses. The rapid expansion of the coal seam gas industry in the rich farming region of the Surat Basin (Darling Downs) may poses significant risks to agricultural production and water supplies where agricultural production in the Surat Basin is worth $1.5-2 billion. The coal seam gas industry is likely to drill up to 40 000 wells in Queensland by 2030, taking a minimum one hectare each of prime agricultural land each. Yet many people believe that there are many unanswered questions about its broader impacts which have alarmed farmers who fear that their livelihoods and the country’s food security may be put at risk. The water that comes out of the coal seams contains a lot of salt, something like five to eight tonnes per megalitre and up to 2.8 million tonnes of salt could be brought to the surface by coal seam gas mining to impact local prime farm soils. This seems like an ideal topic for an EEI. You may like to find out what chemicals are in coal seam gas water and investigate their effect on the growth of plants (but don't even consider the BTEX carnicogens benzene, toluene, ethylbenzene and xylene).

Surface water can be contaminated with the toxic chemicals used in the fraccing process, including the so-called BTEX group (benzene, toluene, ethylbenzene and xylene), as well as salt and methane.	Drilling for gas: Queensland's new coal seam gas industry is booming - but it is not without it's concerns.

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●    Movement of plant stems
The growing tip of a stem does not grow directly vertically but moves upwards in a helical path.  The question is whether there is a difference in the magnitude of the movement (called circumnutation) in shrub plants and twining climbers.  What environmental factors affect the movement e.g. will it continue in complete darkness?  What happens if a piece of vertical fencing wire is placed in the path of a twining stem of leaf tendril? Darwin’s method of examining circumnutation works well even though it is 100 years old!  The idea is to mount a sheet of glass about 10 cm above the plants and to line up the apex and put a spot on the glass.  Doing this every couple of hours gives you a record like that in the diagram of the plant’s movement. What do you think causes the movement of the tip? How will you be sure wind, drought etc. are not affecting your plants? How are you going to quantify the magnitude of the movement? How will you be sure that phototropism is not affecting your experiment? Can a given twining plant climb around supports of different sizes? What is the critical cylinder radius above which a plant is no longer able to twine? What is the effect of friction in the vine ability to grasp the pole? Similarly, what is the pressure generated by a plant on the pole? Click Project 4-9 for Prof. Jennifer McComb’s resource sheet. The figure below on the right has been taken from "Mechanics of Climbing and Attachment in Twining Plants" by Alain Goriely and Sebastien Neukirch, Physical Review Letters 97, 184302 (2006) - click here to get an extract.

A curling tendril	Circumnutation showing the continuous, almost helical, curling followed by the anchor that provides tension in the filament.

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●    Floral clocks
The timing of flowers opening and closing and of pollen shed is well known for European and horticultural plants.  In fact Linnaeus in 1748 made a floral clock in his garden so that you could roughly tell the time of day by seeing which flowers were out!  Similar information is not available for most Australian wildflowers. Some species have flowers open only once, others several times.  Do learn about the structure of a daisy “flower” before tackling these. For some species like Hakeas and Banksias with spikes of flowers the number of newly open flowers as well as the time of opening is of interest. What might control time of flower opening and pollen shed?  Do you expect differences in opening time on cooler days, wet days, and overcast days? Do you expect any difference in time of pollen shed between flowers pollinated by bees or moths, or wind? Click Project 4-10 for Prof. Jennifer McComb’s resource sheet.

Mirabilis jalapa (The four o'clock flower) opens in mid- to late-afternoon and closes again the next morning.	Hartweg's Evening Primrose (Calylophus hartwegii)  opens in the evening and closes the next afternoon shortly before new flowers open.

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●    Wind borne pollen
Pollen carried by wind can be taken to very high altitudes or hundreds of miles out to sea.  However the distance from the parent plant that most of the pollen actually gets may be surprisingly small. Selecting a pollen source is the difficult bit.  It must be a plant that sheds lots of pollen and the pollen must have a distinctive shape.  There must be no other plants of this species in the area.  Neither can there be plants of another species with a similar sort of pollen in the area.  A suitable plant would be a pine tree (an introduced plant) on a farm with no other pines around; a patch of Juncus (rush) in a wet spot with no other rushes (or bulrushes) around etc. Are you going to expose slides only on the windward side of the tree or on all sides.  How are you going to arrange to have slides exposed all at the same time?  For how long will you expose slides?  Will you shut down your experiment if the direction of the wind changes? What environmental factors will you monitor while the slides are exposed? Click Project 4-11 for Prof. Jennifer McComb’s resource sheet.

Coloured scanning electron micrograph (SEM) of pollen grains of the elder tree, Sambucus nigra. These grains are wind-borne pollen.	Absinthe (Artemisia absinthium) wind-borne pollen may cause allergy in some people.

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●    A pollen calendar
Pollen in the air may cause hay fever in susceptible people.  For this reason in spring and early summer, daily pollen counts are carried out in some cities and the results published in newspapers and on the internet.  For an EEI you could compare published data with what you can collect in your own district. Pollen can be collected by the gravity method – expose slides coated with vaseline for one day.  What other “objects” apart from pollen might you expect on your slides? How are you going to identify the pollen you find? Could a local doctor or hospital give you data on frequency of onset of asthma to correlate with your pollen counts? Perhaps you could investigate and compare the accuracy of various methods. Click Project 4-12 for Prof. Jennifer McComb’s resource sheet. Examples of pollen calendars for Queensland and Australia can be seen at http://www.weatherzone.com.au/pollen-index/qld/brisbane/brisbane  and an allergy calendar at http://www.allergy.org.au/content/category/3/48/241/

Pollen calendar from the UK

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●    Pollen in honey
Some people claim they are allergic to honey because of the pollen it contains. During spring, bees flit from flower to flower and collect nectar, inadvertently collecting pollen from the flowers they've visited along the way. The honey that they produce will therefore contain some of these pollen. Honey is sometimes sold with the different flavours kept separate (e.g. karri, white clover etc.) but more often as a blend.  The question is whether different sorts of honey have a distinct range of pollen types.  Note, however, that commercially produced honey may not contain pollen as these are filtered prior to bottling. Honey from small backyard producers are your best bet. A study by Helbling and co-workers (reference below) showed that 75% of honey-allergy sufferers were sensitive to dandelion honey.  For an EEI would you just score presence or absence of various sorts of pollen or are you going to estimate frequency as well. How are you going to identify the sort of pollen that you find? (it may be impossible, in which case good drawings should be made). Are you going to “stick” to local pollen or look at some from overseas as well. Click Project 4-13 for Prof. Jennifer McComb’s resource sheet.  Note: this EEI does not involve manipulating variables; instead it relies on natural variation.
See "Allergy to honey: relation to pollen and honey bee allergy" by A. Helbling, et al, Allergy, V 47, No. 1, pages 41–49, February 1992.

Honey bee collecting pollen	Dandelion pollen (pictured) is notorious for causing allergies in honey.

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●    What causes the death of annual plants?
Some trees live for thousands of years but at the other end of the scale annual plants die after a year or less – why?  It is not fully understood but it is known that you can extend the life of annual plants by removing the fruits.  A good project would be to investigate how long you can extend the life of the plant if you remove the flower buds; the flowers after pollen is shed, the young developing fruit, the immature fruits, the mature fruits?  However, this may take to long to carry out and only be successful if you began earlier than the rest of your class. As a related issue you might compare the total yield of fruit from your plant if you remove fruit as it matures rather than do one harvest when the plant dies. Plants like legumes or tomatoes which flower on side branches are suitable to use, but you might also like to include something like sunflower in which the top growing point is “used up” in producing the inflorescence. Click Project 4-15 for Prof. Jennifer McComb’s resource sheet.

If you want to form just a few large pumpkins fruits per vine, pinch off pumpkin blossoms and small fruits. The plants will send more energy into the remaining fruits and they will grow larger.	If tomato transplants have small fruit at planting time, remove fruit to prevent stunting the plants.	Start thinning gooseberries during late Autumn, removing about half the crop. This will give a longer cropping season and leaves others more room to grow to a larger size.

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●    Seed germination
The environmental conditions that stimulate seed germination are poorly understood for many Australian native plants.  For an interesting EEI you could investigate the conditions needed for germination of several related species, particularly those with horticultural value. Hint: select species for which you can obtain large number of seeds so that you can have a good experimental design.  Try and find out when the seeds germinate in the field as this might help you determine the most likely treatments to use.  Avoid using orchids as they may have very special requirements like a suitable fungus being present. Factors to investigate include: hard seed coats (common in legumes); an impermeable seed coat (prevents water uptake); germination inhibitor (causing dormancy) - some seeds contain substances that prevent germination and these inhibitors are leached out over a period of time (maybe years); temperature requirement (many seeds will germinate only at a particular temperature); light requirement (some seeds require light to germinate (often fairly small ones) or just the opposite – they won’t grow except in the dark. Think carefully about how many factors you can test with the number of seeds you have in hand. Click Project 4-18 for Prof. Jennifer McComb’s resource sheet.

Smoke is a critical factor for promoting germination of seeds in areas subject to bushfires. For example, Grevillea and Hakea (Proteaceae) germinate in response to fire-related cues such as heat and smoke. The seed coat is responsible for dormancy in G. linearifolia (pictured).	Acacia seeds need to be pre-treated with near-boiling water. Then the seeds are then ready for sowing. This photo shows Acacia baileyanna seeds with the radicle emerging after boiling water treatment.

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●    Dispersal of plants in clothing, towels and rugs
Humans may unknowingly carry around weed seeds particularly if they have brushed past plants or gone for a bushwalk. Surely you’ve walked through long grass and found your socks covered with Cobbler’s Pegs which you’ve picked out at home and disperse. Pretty clever seeds! Interesting research has been done by Ken Scott from the School of Environmental and Life Sciences, Charles Darwin University (reference below). He investigated the potential of Gamba Grass (Andropogon gayanus) seeds to be dispersed unintentionally attached to the clothing and backpacks of four people while performing field work in a Gamba Grass-invaded savanna in northern Australia. Gamba Grass seeds attached to, and were carried by, each subject during the course of field work. One person carried 65 seeds, while another carried just eight. They stuck to water bottles, and in the crevices of shoes and socks, rather than on the exterior of clothes. This suggests an interesting topic for an EEI and it would be worth reviewing his journal article. Perhaps you could look in or on shoes and boots, stuck in tread or on shoe laces; in socks, trouser cuffs and pockets, on coats (particularly sheep skin coats), beach towels, travel and picnic rugs car floor mats and car carpets. Maybe a friend living in a country area will clean his door mat for you and send you the specimen (it is illegal to send soil specimens interstate).

The extraordinarily efficient barbs of the Cobblers Peg (Bidens pilosa), otherwise called “Farmers Friend” because the seed sticks to you.	Gamba grass seed has little barbs that make it stick to everything. It is a Class 2 declared pest plant in Queensland. It was introduced into far north Queensland as cattle feed but it also has significant negative impacts.	Gamba grass roadside infestation on Rum Jungle Lake road Northern Territory. It invades non-grazed parcels of land such as conservation areas, semi-urban residential land and mining leases and can replace native grasses thereby reducing natural biodiversity on non-grazed land.

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●    Dispersal of plants by vehicles
Vehicles may carry seeds in cracks or in mud and provide a threat to quarantine barriers.  For example, cars brought in from overseas are steam cleaned before being delivered to their owners.  You could survey the seeds/plant material carried by a range of vehicles. You could compare what is caught in say tyre tread of different vehicles or you could deliberately wash a vehicle thoroughly before a long journey, or a journey through a scrubby area and then wash it again afterwards. How will you identify what grows?  How will you know if everything has germinated?  How long will you wait for things to germinate? Click Project 4-20 for Prof. Jennifer McComb’s resource sheet.

Tiger pear (Opuntia aurantiaca) is a native of South America. It is believed to have been introduced into Australia as an ornamental garden plant during the early 1800s.The segments, easily detach from parent plants and attach to passing animals, humans or even to the tyres of motor vehicles. Tamworth NSW	Feathertop grass (Pennisetum villosum) grows along roadsides as it is dispersed by car tyres. It is a pest and has to be constantly mowed by local councils.

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●    Germination and establishment of mistletoe
Mistletoe seeds are easy to germinate but adult plants occur on a restricted range of hosts.  Is this because seeds never get deposited on other plants?  Or if seeds do arrive on other plants, how big does the hopeful mistletoe grow before it is prevented from attaching? The common mistletoe Amyema preissii is found mainly on Acacia but also on Cassia and Eucalyptus. This project is particularly suitable for students living in the wheatbelt of Western Australia where heavy infestations of Acacia acuminata occur but could be adapted for other species and locations. Click Project 4-21 for Prof. Jennifer McComb’s resource sheet.

If you break the skin of a mistletoe berry, you see a liquid, transparent viscous liquid and a milky-white little ball of firm pulp in which there is one single seed.	Mistletoes are dispersed by birds. Chemicals in the fruits of mistletoes may manipulate the passage rates of the seeds through the digestive systems of these birds and, in so doing, manipulate the probability that seeds are defecated on host trees that are genetically similar to those that they are locally adapted to (in this case an Acacia raddiana host).

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●    Competition between weeds and desirable plants
Everyone hates weeding the garden.  It is known that weeding vegetables during the early weeks of their growth gives a big increase in final yield, but that weeds established after a certain time have little effect on yield.  That suggests an interesting EEI: could you find out when you can hope to stop weeding your vegetables? There are two ways of tackling this.  You might plant the vegetable seeds and let the local weeds do their thing, or you might start in weed free soil and deliberately plant weed seeds at a certain density at specific times.  The second approach gives a better experimental approach as you can control density of weeds. Click Project 4-22 for Prof. Jennifer McComb’s resource sheet.

Weeds are many home gardeners’ biggest enemy.	Roundup and other chemicals may seem like the best weapon in the arsenal against weeds. However, many experts discourage the use of chemicals. They can leach into fruits and vegetables.	Severe weed infestation can lead to total crop failure. Even normal conditions of weediness cause very significant losses to the farmer, perhaps 50% or more of their yield.

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●    Growth of weeds
Many persistent weeds owe their nasty reputation to their ability to regenerate from either seeds or from vegetative structures and to their ability to grow up from considerable depths.  For an EEI, you might investigate for example the depth from which bulbs of Oxalis (sour sob) or runners of kikuyu grass, etc. will emerge.  Alternatively, you might investigate how small a piece of couch, veldt or crab grass is sufficient to establish a new plant. Although weeds are very successful in your garden, for experimental purposes it is better to grow them in pots or seed trays so you can control the experimental conditions more easily. How are you going to standardize the material you start with – bulb weight, size, number of nodes on a runner, its length?  Are you going to leave existing roots and leaves on or cut them off etc.?  If taking small bits off a runner it may be important to note the physiological age i.e. how far back from the apex a particular piece is taken. Click Project 4-23 for Prof. Jennifer McComb’s resource sheet.

Clover is a very common weed of lawns. It has leaves with three leaflets, and creeping stems that set roots at whatever point they touch the ground. Clover is a member of the pea family, Fabaceae. This means clovers can fix nitrogen from the air and therefore they favour poorly fertilised lawns.	Bindii is the curse of homeowners and children.  By the middle of spring each rosette of leaves contains a flower head with many spines. Seeds mature and drop from the plant by about the middle of summer.	Kikuyu is a perennial ground-hugging grass which spreads by runners. It is cultivated for pastures, lawns and playing fields and is a common weed of gardens and roadsides. It is recognised as a weed in Queensland and spreads from deliberate plantings and sites where garden waste is dumped.

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●    Ecological effects of plant chemicals
It has been known for a long time that some plants grow well together while in other cases one plant seems to prevent the growth of another by the chemicals it produces.  This is termed allelopathy.  An interesting EEI would be to find whether there is a scientific basis for the observation that various species of plants can inhibit the growth of other plants. Organic and inorganic substances including growth regulators can be leached from the leaves or roots of plants by rain, influencing the growth of nearby plants of the same or different species.  Volatile substances are also known to be effective.  Plants that are affected can be of the same species and/or different species.  Insects too can be repelled. There is much non-scientific literature on companion plants, and some of these observations might be explained by allelopathy. However, studies by CSIRO concluded that allelopathy is likely to be a cause of understorey suppression by Eucalyptus species especially in drier climates (reference below). How will you first prove that allelopathy exists in your system? How will you then find out where the toxin is coming from? Click Project 4-24 for Prof. Jennifer McComb’s resource sheet. Reference: An Assessment of the Allelopathic Potential of Eucalyptus, FE May and JE Ash, 1990, Australian Journal of Botany 38 (3) 245 - 254.

Probably the most well-known allelopathic plant is the black walnut (Juglans nigra) tree. All parts of the tree – roots, bark, leaves, nuts, and even rainwater that falls off a leaf–release an allelopathic substance called juglone.	Casuarina equisetifolia litter completely suppresses germination of understory plants as shown here despite the relative openness of the canopy and ample rainfall (>120 cm/yr) at the location.	In this high school biology experiment, the student looked at the effects of allelopathic compounds from each of daffodils, apples and lemons on the germination and early growth of lettuce seeds

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●    Litter decomposition
The breakdown of leaf litter is an important part of the cycling of nutrients in the ecosystem.  You could do some experiments to relate the rate of decay of leaf litter to the nature of the plant tissue involved, the soil organisms present and the soil water supply. The succession of fungi associated with the decomposing leaf litter of Eucalyptus regnans was studied by the CSIRO in order to relate the degree of decomposition of the leaves to the mycofloral population. Species of Coelomycetes and some Moniliales were the important initial elements of the mycoflora in the litter, but species of Penicillium and Mucorales succeeded them on leaves in advanced stages of decomposition. For an EEI you could use leaf tissue of contrasting types – Eucalypts, pines, Banksias, and herbaceous plants like cape weed, clovers, grasses etc. How will you study the “nature” i.e. hardness of the plant tissue involved? How will you get comparable initial samples of different species which have different shaped leaves? Click Project 4-25 for Prof. Jennifer McComb’s resource sheet.

Fungus decomposing Eucalyptus regnans litter.	Can you see the camouflaged 20mm flightless nymph Gumleaf Grasshopper, Goniaea australasiae, amongst the decaying eucalypt leaf-litter? Click the image to see a close up of it.	Coelomycetes on a cashew leaf.

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●    Marine environments
Each year many tonnes of leaves and wood from terrestrial plants are deposited in lakes and rivers and eventually carried out to sea.  This suggests a good EEI: you could study the rate of decay of various types of plant material under water. You may wish to compare the rate of decay of material submerged at different depths or buried in the substratum. It might be of interest to compare the rate of decay in an anaerobic stagnant swamp mud and a fast flowing clear stream. Click Project 4-26 for Prof. Jennifer McComb’s resource sheet.
 

Eucalypt leaves were placed by CSIRO at two sites in an intermittent stream during summer to examine the hypothesis that terrestrially-exposed leaf litter accumulates a richer microbial flora than submerged leaves.	In woodland streams, leaf litter is an important energy source and, among the fungi, aquatic hyphomycetes play a pivotal role in the decomposition of dead leaves in these ecosystems.	There are biologically important differences among leaves of different species that may affect microbial community structure, decomposition, and nutrient availability - in this case - underwater.

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●    Litter under trees
Many people hate raking leaves off lawns so they plant evergreen eucalypt trees rather than deciduous trees in their gardens.  It seems however, that eucalypts drop leaves, twigs, bark, flower parts and fruits in vast amounts and the gardener hasn’t solved this problem.  This is even greater when all the litter falls into a swimming pool and blocks the filter. For an EEI  you might like to compare the seasonal occurrence of litter beneath eucalypt and deciduous trees (but recognise that this would have to be over a longer period of time than a normal EEI).  You may also compare pines. How many replicate trays should be used? Are you going to work in a garden situation or a native stand of eucalypts? There is an interesting research article by Prof. Ray Specht and Yvonne Brouwer from the University of Queensland Botany Department entitled "Seasonal Shoot Growth of Eucalyptus species In the Brisbane Area of Queensland"  in the Australian Journal of Botany, V 23, No. 3, 1975, pp. 459-474. The appendix contains data on leaf fall for many Australian native plants. Click here to read this appendix. Also, you can click Project 4-27 for Prof. Jennifer McComb’s resource sheet.  Note: this EEI does not involve manipulating variables; instead it relies on natural variation.

Acacia aneura sheds leaves at the greatest rate from August to November.	For Eucalyptus regnans it is from Dec-April.	... and for Leptospermum, the time for greatest leaf fall is Oct-Jan

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●    Growth of isolated roots in sterile culture
Various parts of a plant are normally linked together – leaves, stems, roots, etc. but by growing the parts separately under sterile conditions it is possible to find out if each can grow independently, or whether it is dependent on material passed from other parts of the plant.  You might like to try and get tomato roots to grow cut off from the top of the plant. Even to get the initial cultures growing well is an achievement but having mastered this you might like to investigate which tomato cultivars grow best, or to try using other plants. You could also compare growth in the complete medium compared with growth in distilled water, or water with 20% sucrose.  If you are preparing your own media you could investigate the effect of different levels of sucrose, or of leaving out the vitamins. Click Project 4-28 for Prof. Jennifer McComb’s resource sheet. Click here for Jennifer's "Sterile Media" instructions.

The standard protocol for performing plant tissue culture experiments is fairly basic. It involves production of plants from very small plant parts grown aseptically (free from any microorganism).	Sweet cherry micro propagation. The container allows the environment and nutrition to be controlled.	Areas of tissue culture collection - buds, nodes, leaf segments, root segments.

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●    Plant callus culture
As a plant grows the cells in various organs mature and stop dividing.  However, under certain conditions such as wounding, some cells can be stimulated to divide and form a mass of disorganised (= undifferentiated) cells called a callus.  This can be used in studies of plant biochemistry, mutation, regeneration of shoots and roots from the callus and plant breeding.  You might attempt to grow a callus from the stems or roots of some plants in sterile culture. Carrot root is a good tissue to start with.  The method involves sterilizing the outside of the carrot then cutting out small pieces and placing them on a medium containing hormones that cause cells, particularly parenchyma and cambial regions to start dividing. Click Project 4-29 for Prof. Jennifer McComb’s resource sheet.

Callus Nicotiana tabacum. In biological research and biotechnology, a callus of cells is a mass of undifferentiated cells. In plant biology, callus cells are those cells that cover a plant wound.	Callus growing on a tobacco plant (Nicotiana tabacum).	Comparison of crown galls (callus) on wild-type tomato (A and C) and the genetically engineered B and D type where it is smaller.

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NOTE: many of the suggestions below involve rates of change (growth rate, germination rate, transpiration etc). You should read the note on "identifying variables" in the description of the “best conditions for growth of a plant" EEI above.

●    How does cold storage affect the germination of seeds? Possible factors: type of seed, length of storage, temperature of storage.

●    The relationship between speed of germination and growth rate

●    Different planting depths will effect the germination rates of seeds

●    Soil with higher soil to seed contact (silt) will have a higher germination rate than those in soil with less contact

●    Chemicals and/or factors affecting the maintenance/survival of cut flowers

●    Response times of sensitive weed under various environmental conditions

●    Effect of household cleaners (other household chemicals) on the growth of plants….. including aquatic and terrestrial. Need to justify why they would have an effect.

●    Finding the optimum concentrations of a hormone in growing tissue cultured plants

●    Plants growing tips will bend towards light, and if the growing tip is removed, the tip will not bend How much of the tip needs to be removed?

●    Effect of environmental conditions on the rate of transpiration of plants using a potometer

●    The effect of humidity on the germination of plants, fungus, seeds…..

●    The effect of duckweed on nitrogen levels in water   

●    The effect of light wavelength on the growth of lettuce

●    The effect of a natural germination inhibitor on the germination of plants (different species)

●    The effect of soil density/depth/structure/type, on the germination/growth rate of plants

●    The effect of salinity on the germination of birdseed

●    The effect of calcium on the germination of beans

●    The effect of pH on the growth of duckweed

●    The effect of temperature on the germination of duckweed

●    The effect of gibberellins on the growth of roots

●    Effect of gibberellins on vegetatively propagated plants … eg basil root growth

●    Effect of geotropism on the growth of plants

●    Effect of phototropism on the growth of plants

●    Determination of the amount of plant mass that needs to be removed to kill weeds

●    Effects of ethylene on ripening …. Either ripe bananas or hormone

●    Determine what effect if any, the amount of stored food has on the growth of potato buds (eyes)/cane billets/

●    Comparison between vegetative propagation of plants and germination of seeds

●    Investigate the various methods of seed distribution….. possibly find links between seed types and another factor like germination rates, method of germination etc

●   How would drought affect the rate of photosynthesis in plant leaves?

●   How would drought affect respiration in plant leaves?

●   How does phototropism affect seedling growth?

●   Does grey water/bore water damage root hairs? Make a time lapse video showing growth of root hairs

●   Does grey water/bore water affect the rate of germination of seeds?

●   Does detergent affect the rate of osmosis in plants?

●   Are cell membranes damaged by washing powder?

●   Which grass species will grow best in drought conditions?

●   Do cacti lose any water in dry conditions? How do they survive?

●   Eucalyptus leaves hang vertically in hot weather. Why is this? How could you prove the benefits.

●   The rate of fall of, and distance travelled by, winged seeds in relation to their structure.

●   Testing for salt tolerance or lead tolerance in races of grasses

●   Growth of duckweed (Lemna species) at different levels of added nitrate and/or phosphate to simulate eutrophication.

●   Growth of duckweed (Lemna species) at different levels of added detergent to simulate pollution.

●   Population dynamics of plants in permanent quadrants; death rates of seedlings and mature plants.

●   Birth and death rates of different leaves on the same plant or leaves on plants from contrasting habitats.

●   Mineral nutrient requirements of plants; water and sand cultures.

●   Tissue cultures of plants in sterile conditions on agar.

●   The effects of different water regimes on plant growth.

●   Inter-specific interaction between clover and grass; addition of fertilizer.

●   Effects of various wavelengths of light, particularly red: far-red ratio, on seed germination, the tropic response of plants.

●   Factors affecting aerial (adventitious) root growth in ivy.

●   Light compensation points of sun and shade plants.

●   Influence of different wavelengths of light on the phototropic response of plants.

The following suggestions involve hypothesis-testing research questions not involving artificial manipulation of variables (relying more on natural variation of variables). This type of investigation is known as a "correlational study" as you you look for correlations between variables rather than artificially manipulating them.

●    Compare the physiology of different species of leaves (mesophyll cells, stomates, chlorophyll distribution and density)... you may use a microtome to section specimens for microscope viewing. This could be tested with a hypotheses like:

• the higher up in a canopy, the greater the abundance of stomata due to an increased capacity to photosynthesise in the presence of a greater concentration of sunlight;
• the leaves at the top of the canopy will have less mesophyll as they are exposed to more sunlight and therefore would lose more water due to evaporation;
• plants which live in the understory will have a higher concentration of chlorophyll as they must utilise as much sunlight as possible which filters through the canopy.

●    Are the stomates on all plants the same size? shape? distribution? Investigate with the Proscope.

●    Do young leaves have the same density and distribution of stomates as older leaves? You could investigate with the Proscope. Possible hypothesis: The younger leaves of plants have less stomata due a reduced need for photosynthesis in new leaves.

●    What controls the opening and closing of stomata on leaves? Use the Proscope to investigate this. Students could investigate the effects of concentration of sunlight on rate of opening, maximum size of opening and compared to different plants in different environments (rainforest to coastal leaves etc). 

●    Compare the reproductive structures of flowers, native – exotic; self pollinating – cross pollinating.

●    Compare the chlorophyll in leaves from the top of the tree to the bottom of the tree (no manipulated variables).

●    Comparison of stomata from plants adapted to different climates/microclimates (dry vs wet environment).

●    Trees and grasses will contain different pigments in their leaves.

●    Pollen counts, made by exposing sticky slides to the atmosphere on several successive days, correlated with weather data and hay fever suffering.

●    Variation in the size of pollen grains in different species of flowering plants.

●    The time and location of most active cell division in root tips.

●    Thin-layer chromatography of flower pigments in closely-related species.

●    Pollination; flower constancy of pollinating insects; pollen identification from insects; flower preferences in relation to tongue length; role of flies in pollen-eating and pollination.

●    Mosses and algae on north-south sides of walls or different levels up a salt marsh; distribution pattern in relation to desiccation tolerance.

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Fungus Options

●    Dung Fungi
Fungi play an important role in decomposing animal dung and recycling the nutrients it contains. The spores of these ‘coprophilous’ fungi are eaten along with the animals food, the fungal hyphae grow in the dung and fruiting bodies are produced on the surface of the pellet. Various fungi appear in succession. A good EEI might be to investigate the succession observed on different kinds of dung. Alternatively, the fungi that grow on dung from a free running animal could be compared with those from a caged animal fed with pellets. You might wish to determine which of the fungi are phototrophic (i.e. shoot their spores towards the light) or how far the spores of various fungi can be shot. Click Project 1-1 for Prof. Jennifer McComb’s resource sheet. Note: this EEI does not involve manipulating variables; instead it relies on natural variation.

There are also various mushroom-producing coprophilous species. This one is Panaeolos sp. on buffalo dung.

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●    Fungi that break down hair and nails and insect skins
Things like sheep horns, wool and hair, bird feathers, animal nails, insect skins etc., are of keratin and chitin. These are rotted away by fungi called keratinolytic and chitinolytic and a good EEI might be to investigtae the abundance and rate of breakdown of such fungi in your local soils. Alternatively, you might want to study how fish scales rot away and do some experiments in fresh or seawater with aquatic sediments. How might you actually measure the rate of breakdown? How will you score the frequency of the various fungi so you can compare the different sources of soil? Click Project 1-2 for Prof. Jennifer McComb’s resource sheet.

White Line disease is an infection horses’ hooves, caused by anaerobic keratinolytic bacteria.

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●    Isolation of fungi from soil
Many fungi occur in soil. Some are saprophytic on animal and plant remains, others are plant parasites. A few trap and digest soil nematodes and other soil animals. In turn, the fungi are eaten by soil animals like springtails and mites. A good EEI might be to isolate soil fungi and compare the frequency of different fungi from various types of soil? How will you check that the fungi you grow are actually from the soil and not from faults in your sterile technique? If you are hoping to estimate the number of fungi per gram of soil, at what stage will you weigh your sample? (You will use a lot less than 1 g). Are you going to sample soil from the same place at different times of the year, at different depths, or from a sequence of places along a transect, say from beach through sand dunes into forest, or from burned to unburned areas of bush? Click Project 1-3 for Prof. Jennifer McComb’s resource sheet. Note: this EEI does not involve manipulating variables, instead it relies on natural variation.

Aspergillus fumigatus conidia (spores). A. fumigatus is a saprophytic fungus and is the main cause of the human disease, aspergillosis (allergic aspergillosis or respiratory infection).

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●    Nematode trapping fungi
Several fungi in soil can trap and digest nematodes. Some of these fungi produce sticky hyphae or spores which become attached to, and eventually penetrate passing nematodes; other fungi produce ring traps that inflate on contact, or coiled hyphae in which the nematodes become entangled. A good EEI might be to grow nematode-trapping fungi and see them catch the nematodes? Are you going to examine one soil type in detail or look at different soil types; sand, compost, mud from gutters, mud squeezed out from mosses, rotting wood? Do you want to do some experiments on why the traps are only produced when there are nematodes present? Will dead nematodes stimulate development; will the liquid in which the nematodes have been growing stimulate development etc.? Click Project 1-4 for Prof. Jennifer McComb’s resource sheet. Note: this EEI does not involve manipulating variables; instead it relies on natural variation.

Nematode-trapping fungi occur naturally throughout the environment, and more than 150 species have been identified. These fungi have evolved a wide variety of devices to trap or invade nematodes and use these animals as a source of nutrients.

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●    Freshwater fungi
Some mould fungi live on submerged decaying dicot leaves and produce non-motile spores (conidia) underwater. These fungi (aquatic hypomycetes) have been extensively studied in Europe and America but little is known about them in Australia. Once you have discovered a source of these fungi you might look at their seasonal abundance and their occurrence on different kinds of leaves. Alternatively, you might compare their abundance in different sorts of habitats – fast flowing streams with tree lined banks (eucalypts and native plants or introduced willows etc.) swampy areas with some water flow (plants like Typha-bullrush and Juncus-rush), or stagnant ponds. How will you figure out from which plants your decaying messy leaves came? How will you distinguish aquatic hypomycete conidia from conidia of terrestrial fungi, moss and fern spores, pollen and so on? Is it possible to determine spore concentration in water by collecting foam or do you need running water for this? If you count spore numbers how will you back calculate to the volume of river water originally sampled? Click Project 1-5 for Prof. Jennifer McComb’s resource sheet. Note: this EEI does not involve manipulating variables; instead it relies on natural variation.

The aquatic hyphomycetes were first recognized by Ingold (1942) and are also referred to as the Ingoldian hyphomycetes in his honor. The one shown here is Tricladium chaetocladium

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Protist Option

Slime moulds, like Physarum polycephalum are part of the kingdom Protoctista. This is probably the least understood of the five kingdoms of life. One of the most interesting things about Physarum polycephalum is that it shows a quality that could be called primitive intelligence. Studies done by Dr Toshiyuki Nagakaki and colleagues in Japan have shown that Physarum polycephalum can find the shortest distance through a maze. When the Physarum polycephalum organism is chopped up and dropped into a labyrinth (a maze), they put themselves back together and start to move. If a food source is placed at the entrance and exit to the maze, they avoid dead ends in the maze and form a connection (as a single tube) between the food sources. In all cases, the Physarum polycephalum chose the path that was the shortest between the two food sources. In a way, it "solved" the puzzle of finding the shortest path through the maze! The paper was printed in Nature V407, 28 Sept 2000, p 470  (click to download). At St Ursula's College, Yeppoon Queensland, HOD Science Barbara Pearson said that her students tried such variables as the type of food preferred (start with oats), time taken, complexity of maze, hazards such as light source, use of Vaseline on maze. Plenty of webpages with ideas.

Physarum polycephalum	Photo of slime mould in maze - taken from Nature article.

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Animal Options

Note: very strict rules apply to the use of animals in schools in Queensland. Information can be found at the official link Animals in Education.

●    Effect of temperature on reproductive success of sea monkeys.
Moreton Bay College runs an open inquiry EEI in Year 12 in which students have to investigate the effect of environmental conditions on the growth and development of an animal (or reproduction if non-vetebrates are concerned). In the one pictured below, this group is considering the effect of temperature on commercial sea monkeys (brine shrimp). Native ones have too long a life cycle to be any use in this experiment. If you want further information email their ever-helpful biology teacher Ms Josie O'Shea: osheaj@mbc.qld.edu.au
 

Setting up the equipment.	Counting the monkeys

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●    Fruit Fly Inheritance
The fruit fly Drosophila melangaster is, and has been in the past, used for a variety of genetic experiments, including the study of genetic inheritance and to discover that genes were related to proteins.  The fruit fly lifecycle is useful for students to study as it has a short lifecycle (11-15 days), is fairly easy to maintain and has a number of easily identifiable phenotypic features to study.   In this EEI students are required to investigate the effect of an enviromental variable (such as light, temperature or pesticide resistance) on the growth and reproduction of the fruit fly Drosophila melanogaster. In the photos below, this group of Moreton Bay College girls is looking at the effect of alcohol. Fruit flies are bought from Southern Biological for $10 per tube and bred up by the lab staff. Each group need about 8 fruit flies per vial (4 males, 4 females) and about 9 vials (3 treatments x triplicate). A few years ago they tried alcohol on food but that was a disaster, then they tried alcohol on cotton balls (no good) and finally settled on alcohol on filter paper. To analyse "inter-relationships" as per the criteria, it seems logical to try the experiment two ways: 1. control the alcohol concentration (eg 100%) and vary the frequency of exposure); or 2. keep the frequency constant and vary the concentration (30%, 70% 100%, or whatever). To count them, knock them out with Carbon dioxide (acid + marble chips + delivery tube). Other variables that could be considered: temperature, type of food, amount of food, size of container on growth, reproduction of flies. One enterprising group even looked at the effect of cigarette smoke.  Click here to download the EEI task sheet as used by Moreton Bay College (my thanks to Josie O'Shea).

Growing them.	Observing fruit flies in the presence of alcohol.	Carly, Izzy and Hannah's "Drunk flies".

Anaesthetising fruit flies with carbon dioxide gas so that they can be counted and boy/girl ratios determined.	Counting the numbers of boy and girl flies.	Boy, boy, boy, girl, boy, girl, girl.

 

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●    Effect of global warming on pest species.
The temperature of the earth is increasing due to global warming. Could this increase in temperature lead to increased reproduction rates of pest species?

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·         ●    Effect of global warming on marine species.
One side effect of global warming is acid rain. If the pH of the Earth’s waters or environment changes could this affect rates of reproduction or the survival of marine species?

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●    Effect of protein on the growth of fruit flies.
This is another one done by some students at Moreton Bay College. The manipulated variable is the quality of protein used as food for the flies. One type is semolina, the other is Nature's Way high protein food supplement - both of which contain which contains 18 different amino acids but in different proportions and absolute amounts. The photos below will give you an idea of what was done in this EEI.

Semolina contains the same amino acids as Nature's Way Protein Powder but has a greater proportion of non-essential acids such as glutamic acid (36%) and proline (11%) compared to Nature's Way (19% and 5% respectively). Semolina is particularly deficient in the essential arginine (3.6%) and lysine (1.9%).	Nature's Way contains a greater concentration of amino acids (both essential and non-essential) and a greater proportion of essential ones than semolina.	Mrs O'Shea has some clever ideas.

Fruit flies feeding on semolina and Nature's Way.	Adding sodium carbonate powder to hydrochloric acid in the anaesthesising vial to make CO2.

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●    Effect of temperature on the growth and reproduction of the Common Egg butterfly.
These butterflies can be bought from Ross Kendall at Butterfly Encounters,17 Eldon St, Indooroopilly, Queensland Ph 07 3378 1187 or Mob 0402 254 370; Email: ross@butterflyencounters.com.au. He's the guy at Indooroopilly (Brisbane) who keeps the caterpillars under his house and breeds them for weddings. See his webpage at www.butterflyencounters.com.au. I think he's with the Moth and Butterfly Association of Queensland.

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●    Growth response of maggots to various conditions
Suggestion courtesy of Jonathan Grassby, Year 11 Co-ordinator, Craigslea State High School .

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●    Growth rate of chickens eating different feeds
There are several factors that affect the chickens’ growth rate and size at harvest. These include: breed, age at harvest, feeding regime, gender (males grow faster), and age of parent flock (ageing flocks produce bigger eggs and the chicks from larger eggs grow faster). Such factors may make a successful EEI however the code of practice for animals in school scientific investigation lays down very strict requirements on such experiments (see link above). If you plan to do a chicken EEI you should plan a year in advance. An interesting investigation is done by some students at Moreton Bay College. They looked at the differences in growth rate depending on the type of food and feeding regime (as mentioned above). Regular and organic feeds were compared. It should be stressed that the conditions for being permitted to do such an experiment would not allow things like restricting food or water, or providing less than optimum conditions for the animals (correct temperature etc). The advice from Biology teacher Josie O'Shea (osheaj@mbc.qld.edu.au) at MBC is to plan well ahead as the obstacles are great. The photos below provide a stimulus for those considering an EEI of this type. Some interesting background on feed requirements is provided by the Chicken Meat Federation of Australia.
 

The set up.	The two types of feed being used.

Organic chicken feed. Click photo to enlarge to see percent protein.	Regular chicken feed. Click photo to enlarge to see percent protein.

How is access to food controlled - if at all? How can variables be controlled and still meet the code of practice? These chickens are called Tandoori, Tikka and Masala.	Temperature should be between 30 - 32°C. Click photo to see an enlargement so you can read MBC's thermometer.

They start off small and cute.	Need to find a good home for them at the end of the EEI.

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●    Does an individual's ability to return to their normal physiological state, after a period of exercise, depend on individual differences?
The Effects of Exercise on the Maintenance of Homeostasis: Homeostasis is the maintenance of a relatively stable internal environment. However, exercise disrupts homeostasis. The changes that occur in response to exercise are the body’s attempt to reduce the stress that has been placed on the entire organism. Changes that are normal during exercise would be considered abnormal if they were occurring in a non-exercising individual. For example, the level to which the body temperature rises during exercise would be considered a fever if the person were not exercising. Exercise physiology is the study of both the functional changes that occur in response to a single bout of exercise and the adaptations that occur as a result of regular, repeated bouts of exercise. Suggested EEI - courtesy of St Aidan's College, Corinda.

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●    Anaesthetising of barramundi
Clove oil has been used for a number of years to anaesthetize fish in seawater. In fish farming this is essential for performing basic procedures such as weighing, tagging, experimental work and for transport. It considerably reduces pathology risks from stress, injury and accident during handling. Clove oil is distilled from Euglena caryophyllata stems, buds and leaves and has been used on humans for centuries as a local anaesthetic. It is fast, relatively cost-effective and does not harm the fish.

Biology student Cristal Jones of Tully SHS conducted an EEI to determine the optimum concentration of the Clove Oil Anaesthetic for juvenile barramundi. She speculated that Clove Oil, which is not well known or widely used, could become an alternative to the standard phenoxyethanol, quinalidine or benzocaine which are hazardous, expensive, hard to come by in developing countries and sometimes less effective. The relevance of determining the Optimum Clove Oil Anaesthetic concentration formula for juvenile barramundi extends into industrial and commercial situations, scientific studies, veterinary assessments and also in Aquaculture Facilities such as the Barramundi Ponds in the Tully State High School. Although it is preferable for the induction to be relatively fast with a quick recovery period, this is not always practical. Cristal has just finished her PhD in the School of Biochemistry and Molecular Biology at the Australian National University and is now working in the biosecurity field. An article in the Weekend Australian (2 Oct 2010) about harvesting eggs from sturgeon to make caviar explains how sturgeon in Australia are anaesthetised harmlessly with clove oil when they are milked. Click here to download a copy of Cristal Jones's 2003 EEI. Note: her EEI is provided as an example of the work being undertaken and is not meant to be an exemplar of an EEI or of a particular achievement standard.

Capturing the barramundi	Barramundi in the Tully SHS fish tank.

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●    Barramundi experiments
As part of the Great Barrier Reef Marine Park Authority’s Reef Guardian Schools program, Tully State High School has established reef related activities to promote the Great Barrier Reef and increase understanding and appreciation of the local marine environment. One of their programs is Aquaculture studies in which they aim to promote understanding of aquatic environments. There is a specialist aquaculture facility on the school grounds where students learn about the advantages, disadvantages and value of aquaculture in the north Queensland region. For Senior Biology students this facility enables them to do some imaginative EEIs on redclaw crayfish and barramundi. Some of the Research Questions posed by students in their EEIs include:

1. effect of stocking density
2. light / dark effects on growth
3. feed types (pellets, pilchards, prawns, worms (and worm farm worms)
4. which fishing lure is most effective (hooks removed)
5. clove oil anaesthetic - as described above
6. temperature of water
7. water quality (pH, DO, nitrates, phosphates, etc)
8. frequency of feeding
9. clean tank walls as opposed to letting the algae grow on the walls of the tank
10. water depth
11. size of the tank
12. isolation v companionship

Fish tanks at Tully SHS's Aquaculture Centre	Water filtration

 

Students performing their EEI	Capture and tagging a barramundi	Tagged and released

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●    Beetles as pollinators
Some insects like bees usually collect pollen or nectar from only one species on a particular collecting trip, or even over a period of several days.  Consequently, they are very good pollinators as they go from flower to flower of the same species.  Other insects like beetles have the reputation of being less selective and of travelling to flowers of different species; they are thus less efficient as pollinators.  For an EEI you could investigate just what range of flowers a particular beetle visits and consequently the range of pollen it carries. How are you going to keep a watch on the beetle as well as recording the plants it visits in sequence? How are you going to catch your beetle without showering it completely with the pollen of the flower it happens to be on? How will you clean your brush between beetles? What are the floral adaptations for beetle pollination and thus on which flowers are you most likely to find beetles? The abundance of flowering plants of a particular species might influence the animal’s behaviour.  How will you include this variable in your experiment? Click Project 4-14 for Prof. Jennifer McComb’s resource sheet. Note: this EEI does not involve manipulating variables; instead it relies on natural variation.

Beetles comprise the largest set of pollinating animals, due to sheer numbers. They are responsible for pollinating 88% of the 240,000 flowering plants globally.	Argemone has flowers pollinated by beetles, which chew on petals, stamens, and stigmas; although they destroy some of these structures, in the process they transfer pollen to stigmas.

 

Parsonsia eucalyptaphylla flower beetles	Just how "pure" is pure?

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●    Collection of seeds by ants
It has been estimated that there are about 1500 species of Australian plants that are regularly dispersed by ants.  The ants are attracted to the seed because it has a firm fleshy appendage (called an elaiosome) and carry the seeds back to their nests.  Only a little is known about this issue in Australia and could form the basis of an EEI. Be aware that this type of investigation does not involve the manipulation of variables but relies on natural variation. Ant-dispersed plants (dubbed myrmecochorous) are woody shrubs in sclerophyll vegetation. Species in families Rhamnaceae, Fabaceae, Sterculiaceae are commonly ant dispersed as are members of the genera Acacia, Hibbertia, Goodenia. Look up these groups so you can recognize them in the bush. Many species shed their seeds in summer. How will you score your results if ants of several species appear on the scene unexpectedly and a brawl ensues? Are you going to study foraging only during the day or at night as well? Click Project 4-16 for Prof. Jennifer McComb’s resource sheet.

Messor aciculatus ant carrying pampas grass seeds.	Rhytidoponera metallica ant holding a seed of Acacia neurophylla by the elaiosome during seed transport.

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●    Seed survival after ingestion
Not all of the seeds eaten by animals survive the passage through their alimentary canal; thus they end up in the animals’ dung. An interesting EEI would be to find out what proportion of seeds survives the alimentary canal and which seeds are distributed in dung.  The experiment could relate seed size and structure with survival in animals with different types of digestive systems. You should select your seeds from those normally eaten by the animals e.g. oats, clover, medic, ryegrass, etc. and possibly include tomato which has a great reputation for survival.  If the animals normally eat pellets you can make a mash of pellets and seeds and include these in the animal’s food. It would be interesting to include two animals with a contrasting alimentary canal e.g. hens and rats, sheep and horses. A large animal like a horse produces a vast amount of manure, all of which will have to be washed and sieved so use a small animal unless you are very keen! How are you going to compare live seeds in initial samples (before ingestion) with material which has passed through the animal? Click Project 4-17 for Prof. Jennifer McComb’s resource sheet.

Elephant dung with partially digested marula seeds Kruger National Park , Mpumalanga , South Africa.	Dung of the cassowary from the tropical rainforests of North Queensland showing the undigested seeds of the Alexandra Palm, Archontophoenix alexandrae. The cassowary has a very gentle and fast moving digestive tract, so some seeds pass through them without being fully digested.

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●    Effect of household detergents on freshwater organisms
Although many detergents are now what is called “biodegradable”, degradation takes a finite time, and detergents which by one means or another find their way into rivers, lakes, swamps etc. could be quite harmful before they are degraded.  In particular, detergents affect the permeability of biological membranes.  You could investigate the tolerance of certain freshwater organisms to various concentrations of detergents. Organisms easily available in sufficient numbers for testing include mosquito larvae, small arthropods such as Daphnia, freshwater snails, fish, the plant Lemna, and tadpoles. As you will be killing animals you may find it less upsetting to knock off invertebrates rather than vertebrates.  It is important to remember are that it is very difficult to measure when a plant is “dead” compared to an animal, and that some animals like mosquito larvae go through developmental stages during the experiment. Click Project 13-1 for Prof. Jennifer McComb’s resource sheet.

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●    Monitor the population growth of organisms that rapidly reproduce asexually

●    Monitor the metamorphosis of brine shrimp from cyst to adult

●    Gonadotrophic hormone injection of blackbream

●    Compare the histology of animals from various classes, families etc and relate to adaptations

●    Determine the tolerance limits of various organisms

●    Influence of temperature on rainbowfish spawning

●    Reproductive behaviour of aquarium fish.

●    Navigation of ants by pheromones (e.g. in trail-following).

●    Effect of light and/or temperature on the behaviour of fish.

●    Direction-finding in pond snails. (In general snails are good animals to work on: they are easy to keep, move slowly and don’t answer back!).

●    Learning and colour/pattern recognition in relation to feeding behaviour of fishes.

●    Energy budgets of insects of different ages

●    Factors affecting the distribution patterns of different animal species, e.g. planarians, shrimps, barnacles, mussels.

The following are experimental EEI suggestions which do not involve the "artificial" manipulation of variables, rather relying on natural variation. This type of investigation is known as a "correlational study" as you you look for correlations between variables rather than artifically manipulating them.

●    Feeding preferences of dogs/cats/green ants.

●    Compare and display various egg types from a range of organisms and discuss the various adaptations, survival and developmental, the types of eggs convey.

●    Determine the concentration of bacteria in various situations, e.g. milk at different ages, water from local creek.

●    Isolate pure cultures of microbes from soil, the Banyan, the pond or any other safe source.  Check your chosen source with your teacher.

●    Compare the eggs of various fishes and relate the egg’s properties to the niche of the egg and the adaptations it has for survival.

●    Compare the histology of various structures of invertebrates using the microtome…… prepare slides of various structures for various adaptations.

●    Compare the reproductive organs of various fishes….. possibly even various stages of maturity.

●    Analysis of territorial behaviour in birds, e.g. magpies. (Ideal for keen bird-watchers.)

●    Analysis of web-building by spiders as an example of innate behaviour.

●    Stalking behaviour in cats. (In general many interesting projects can be carried out on pets but be sure to adopt a rigorous scientific approach using artificial manipulation of variables or correlation of naturally occurring variables (concomitant variation).

●    How does the shell of a snail grow in size and shape as a snail becomes larger?

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Homeostasis Options

Homeostasis is the condition where the body’s internal environment remains relatively constant despite external fluctuations. It is the job of the body’s organ systems to maintain it, even as they make necessary exchanges with the environment.  Although many projects will be related to homeostasis in the human body, projects involving investigation of Stimulus-Response in invertebrates and in plants are also possible (see Behaviour Options below).

There are several sensors that can be used to provide quantitative data. Diane Mackenzie at Clairvaux MacKillop  focuses on homeostasis in Year 12 EEIs  – using  a number of sensors for measuring surface/skin temperature, ECG, heart rate, hand dynamometer for measuring force or strength, spirometer, respiration monitor belt. Students are taught to use LoggerPro software with some basic sensors in the Junior school.

●    How does human cognitive ability change with temperature change?
Humans can't think straight when they are cold. We all know that. But can this be quantified? If you gave a student some simple maths questions (15 + 8) and noted the score (out of 30) and then had the student climb into a wheelie bin of icy water for 5 minutes - would they be able to do as well on a similar test. I would think not. But, what process is operating here. You'd need some good biological theory to justify your hypothesis before you even started. And are all students the same? Do students with a higher BMI respond with a smaller change in achievement (almost said "ability")? How do you measure a student's core temperature? Photos below courtesy of Moreton Bay Boys College.

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●    How do energy drinks affect heart rate and BP?
Here’s a extract from a newspaper “Energy drinks may help you to exercise but they also raise heart rates and blood pressure, say researchers. They contain chemicals including caffeine and taurine, an amino acid, that stoke up alertness but are potentially harmful to those with heart conditions. A study in Detroit has found they can even harm consumers who are simply sitting still. Dr James Kalus, of the Henry Ford Hospital, said: "We saw increases in both blood pressure and heart rate in healthy volunteers who were watching movies. They were just in a resting state.” This suggests a good EEI. You could compare water, uncaffeinated soft drink, energy drinks (eg Red Bull) and make an assessment of the effect on psychomotor performance (reaction time, concentration, memory) and physical endurance (aerobic endurance - time when maintaining 65–75% max. heart rate) and anaerobic performance (maintaining max. speed) on an exercise bike.

 

Water - the "control".	Or would ordinary sugary lemonade be the "control"?	Red Bull - a can of  independent variable

●    How do caffeinated soft drinks affect heart rate and BP?
Here’s a follow-up to the one above, but without using energy drinks such as Red Bull. Why not see how caffeinated drinks affect BP and heart rate. In this EEI you might like to compare: water, uncaffeinated sugar-sweetened soft drink (eg uncaffeinated Coke), unsweetened caffeinated soft drink (Diet Coke or Coke Zero. Perhaps you could look at psychomotor performance and physical endurance as above.

Uncaffeinated Diet Coke - is the "control" or should water be the control?	Caffeine but no sugar.	Caffeine and sugar.

●     Is reaction time altered following intense exercise? (need more than one type of exercise). How will reaction time be measured?

●     Does reaction time differ according to the time of day?

●     The temperature of the earth is increasing due to global warming. Could an increase in temperature increase the body’s food requirements?

·        ●     Exercising causes the core body temperature to increase. If diffusion rates increase in response to temperature, should food be consumed directly after exercise?

·         ●    What factors have the greatest impacts on reflexes and response time? What is the recipe for maximum response time?

·         ●    Teenagers are said to be most mentally active later in the day. Do reaction times during the day confirm this? Should school hours be altered?

·         ●    Are reaction times affected by food intake, rest, time of day or exercise? If so, should the school day be altered in some way to allow students to achieve maximum alertness.

●    Hot Biceps. Why do my muscles get hot when I use them? How hot do weightlifters/cyclists muscles get? How long does it take for them to cool down?

●    Muscle Fatigue. What causes muscle fatigue? How quickly do muscles recover ? How does training build strength?

●    Cardiovascular fitness. Interval training versus weight training.

●    Heart attack.  What effect does exercise have on an ECG? What does the ECG of a heart attack victim look like?

●    Breathe Deep. Yoga promotes well being and improves lung function – is it a good training technique? What other techniques are used?

●    WII Fit.  Can training improve reaction times – what other factors affect reaction times?

●    Nerve pathways.  Left brain, right brain dominant?

●    Reflex Actions - Can individual differences be attributed to any physical differences.

·        ●     To dance or to run? Which sports increase your fitness faster over a set period of time?

·         ●    Not today!!! Does regular exercise have a greater influence on fitness than sporadic exercise? Should school students be required to exercise everyday?

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Behaviour Options

●    Conditioning mice to follow a stimulus to food….factors affecting ability to run a maze.  From a student (Jessica, Yr 12) at Moreton Bay College: "The question that triggered the topic for this investigation was, “If humans are believed to have a greater learning ability at a younger age, and if they share a similar genetic makeup to mice, do mice learn at younger ages too?” The aim of the investigation was to determine how the factor of age in mice affects their ability to learn how to navigate a maze. It was hypothesized that the younger mice would demonstrate the greatest learning ability, the adults would have a slightly decreased ability and the teenagers having the smallest learning ability".
Here's a little bit of Jessica's introduction: "Each different species of animal learn differently according to their anatomy, physiology and psychology that evolves from environmental pressures over many years. Several factors affect an animal’s learning ability. These include developmental factors – such as age, physiological state and psychological state – and the sensory abilities, as well as the emotional state of the animal at the time of learning. An animal’s ability to learn greatly depends on its capacity to memorise. Mice, which have a remarkable genetic similarity to humans, refer to their episodic memory when learning how to navigate a maze. Episodic memory is the memory of events in our lives which, in the case of a mouse, would be the previous times they had run through the maze. The two learning types that exist for animals are able to be used by mice when navigating a maze: classical conditioning (learning by association) and operant conditioning (learning through a process of trial and error). Classical conditioning is used in maze navigation in that the mouse associates reaching the end of the maze with a reward – usually food or its home. But it does not achieve the same effect that classical conditioning usually achieves, which is to produce a response from a conditioned stimulus (i.e. in Pavlov’s dogs, the bell stimulus producing salivation response in the dogs to replace the food stimulus). Operant conditioning is the major learning in action through the mouse having to trial different directional turns to see which combination leads it to the reward. As the mouse navigates the maze again and again, there are many physical changes that are occurring inside its brain that allow it to learn the correct route.

Note: very strict rules apply to the use of animals in schools in Queensland. Information can be found at the official link Animals in Education.

 

Ebony, Jess and Anna's mouse maze

 

"Tiny" is on the move.	"Tiny" smells the food but is in a dead-end. What to do?

Eyeing off each other.	Sniffing the air in the lab.	Strict animal experimentation rules apply.

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●    Sensation of smell and taste
It is often said that heavy smokers can’t taste and smell things as well as non-smokers.  Can you conduct experiments to show if this is so?  Can you relate your findings to the length of time the people have been smoking and/or the number of cigarettes they have each day? Easiest substances to use are ones that you can measure and dilute accurately so you can find out what is the lowest concentration of a substance your tester can smell or taste (a few suggestions – vinegar, honey, sesame seed oil, chilli sauce etc – don’t use anything poisonous or substances that will evaporate very fast). Many of the things we think we taste, we really smell, and there are only four basic taste sensations, sweet, acid, salty and bitter. Click Project 12-1 for Prof. Jennifer McComb’s resource sheet.

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●    Schooling behaviour of fish
Many small fish show a tendency to school but it is not always clear whether they are responding to each other or to a common external factor.  You can test some of the factors that influence schooling using an aquarium. Although this sort of work has mainly been done using freshwater “tropical” fish, it is equally feasible to use coldwater, estuarine or marine fish – as long as they are small enough. Click Project 9-2 for Prof. Jennifer McComb’s resource sheet. If you plan to undertake an EEI such as this you should be aware of legislation regarding the use of animals in education.

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●    Landing sites of flies
Flies seem to land more thickly on some people’s backs than others.  Do they smell nicer (to the flies!) or is it maybe because they are wearing clothes of a certain colour?  If the smell is attractive enough will the flies worry about colours? To standardize your experiment you will need some cooperative friends to have a swim then to sunbake and work up a nice sweat.  To compare between people simply count numbers of flies in a marked area on their backs at set times. How will you make sure all the bits of cloth smell the same at the beginning of the experiment? Click Project 7-6 for Prof. Jennifer McComb’s resource sheet.

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●    Relationships between green ants and other organisms

●    Defensive behaviours of green ants

●    Innate behaviour of insects to fly, walk etc

●    Hearing of cockroaches

●    Feeding behaviour of different species of fish

●    Attack behaviour of fish to prey

●    Different feeding patterns of fish feeding on different food types, still, moving etc

●    Conditioning of barra to luring (fishing with lures)

●    Conditioning barra to feed

●    Conditioning mice to follow a stimulus to food….factors affecting ability to run a maze

●    Conditioning chickens

●    Chicken behaviour observations

●    Conditioning sensitive weed and venus flytraps

●    Effect of different coloured stimuli on barra feeding

●    Design the most effective lure for catching barra

●    Native Seed germination – heat or hormones – which is more effective?

●    Behaviour of Woodlice – investigate turn alternation using a maze.

●    Osmoregulation in crabs – set up a marine aquarium and investigate changes in salinity

●    Cricket chirping – what affects the rate of chirping in crickets?

●    Diurnal rhythms. What are they? Do they really exist in humans? Why? (Possible ERT stimulus).

 

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