2.1 Practical
Investigation
Practical Investigation Ideas
Micro-organisms
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Do different types of bacteria grow on different foods?
What is the effect of temperature on the growth rate of bacteria?
What factors affect the effectiveness of preservatives on the
growth of bacterial colonies?
Do bread yeast and wine yeast respond in the same way to
ethanol?
What is the effect on the density of soil bacteria of incorporating
different types of organic matter into soil?
Investigate succession on a piece of bread
Practical Investigation Ideas
Plants
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What factors affect the germination of sunflower seeds?
What is the effect of wavelength of light on plant growth?
What is the effect of wavelength of light on the rate of
photosynthesis?
What is the effect of light colour on the growth of seedlings?
What is the effect of different mineral nutrients on seedling
growth?
What is the effect of different brands and types of fertilisers on
seedling growth?
What is the effect of salt tolerance on seed germination?
What is the effect of wind (none, intermittent, constant) on plant
growth?
Practical Investigation Ideas
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Does the effectiveness of different brands of weed killer vary?
Is weed control dependent on the concentration of the
weedicide?
Does planting depth affect the rate of germination in clover and
pea seeds?
Does soil type affect the germination of clover and pea seeds ?
Does soil type affect the formation of roots on geranium
cuttings?
Is hormone rooting powder effective in promoting the rooting
of cuttings?
Does temperature affect germination of clover seeds?
Investigate the distribution of lawn species in the sun and in the
shade
Practical Investigation Ideas
Cell chemistry
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Rate of enzyme action at different temperatures
Transport
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Osmoregulation in Nereis sp.
To measure the heat beat of Daphnia at different temperatures
Compare the transpiration rate in different plants
Respiration
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The effect of temperature on the rate of anaerobic respiration of
glucose by yeast
Biological Concepts
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Enzyme activity
Cell processes such as: photosynthesis, protein
synthesis, cellular respiration, mitosis…
Surface area versus volume ratio
Transport: diffusion, osmosis, active transport
Patterns and interrelationships in populations and
communities
Transport in plants and animals
In the Past…
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To see if different storage places have an effect on the sucrose
concentration in potatoes
To determine whether the sucrose concentration varies between
different root vegetables.
To find which river in the Nelson region has the highest density
of micro invertebrates
To find out what effect the texture of soil has on seed
germination
To find out, if the flow rate in a steam has an effect on the
diversity and the abundance of bacteria and fungi found in the
stream
Does the temperature of sodium hydroxide have an effect on the
rate of diffusion into agar?