Organisms In The Environment Flashcards
What happens during photosynthesis
Light energy is transferred to chemical energy
What is the equation for photosynthesis
Carbon dioxide + water—> (+light energy) glucose +oxygen
What is released as a byproduct of photosynthesis
Oxygen
What is the process for photosynthesis
Carbon dioxide is taking in by the leaves and water is taken up by the roots
The chlorophyll traps the light energy needed for photosynthesis
This energy is used to convert the carbon dioxide and water into glucose
What is some of the glucose is converted into
Insoluble starch for storage
What is the test for starch and what are its results
The iodine test. variegated leaves have patches of green(with chlorophyll) and white (without chlorophyll) only the patches will turn the iodine solution blue black to show that starch has been made
When do plants grow best
When they have enough light, carbon dioxide and water and are kept at a suitable temperature
Why do enzyme reactions slow down
When the temperature falls the enzymes work slower
What will happen if there is too little carbon dioxide- give an example
The rate of photosynthesis will slow down
In greenhouses on a sunny day where there is plenty of light energy available but the plants run out of carbon dioxide
Name a limiting factor that would slow down the rate of photosynthesis
A lack of light
What is a limiting factor
Anything which put a cap on the rate of a reaction
What is the independent variable
The one being tested e.g. concentration of carbon dioxide
What is a dependent variable
The one you measure in photosynthesis it is usually the volume of oxygen produced
Name three substances used for storage in plants
Starch fats and oils
What happens to the glucose produced by photosynthesis
It is converted into insoluble starch for storage
It is used for respiration
It is converted into fats and oils for storage
It is used to produce cellulose which strengthens cell walls
It is used to produce proteins
Why do plants and algal all cells need a supply of mineral ions such as nitrate ions
In order to produce protein. Plants absorb nitrate ions from the soil. Algae absorb nitrate ions from the water they live in
What factors must be controlled in a greenhouse to improve plant growth
Light, temperature and carbon dioxide
What is biomass
Biological material from living or recently living organisms
What are physical factors that may affect the distribution of organisms
Temperature, availability of nutrients, amount of light, availability of water, availability of oxygen, availability of carbon dioxide
Why are there so few animals living in very cold regions such as the Arctic
Very few plants grow there – those that do are very small, so there is little food for animals
What is a quadrat
A square frame which may be divided into a grid
What is a quadrat used for
A quadrat is used for estimating the distribution of living things in their natural environment
What is random quadrat or a transect
A quadrat
What is a transect
A measured line marked between two points on which a quadrat can be placed at equal distances apart.
How can you make sure an investigation is valid
Only the independent variable Should affect the results all other variables must be controlled
Why is it necessary to check the results
To ensure your results are reproducible
Why is it important to get the right sample size
If the sample is too small it may not be representative so the larger the sample size the more trust we can have in the data
Why would there be little point in heating the greenhouse on a summers day
It will be hot enough anyway, so it would be a waste of energy. The rate of photosynthesis may stop if the temperature becomes too high
Why is it difficult to be sure an investigation in outdoor habitats is valid
There are so many variables which are difficult to control
What is meant by the term reproducible results
A measurement is reproducible if the investigation is repeated by another person, or by using different equipment or techniques, and the same results are obtained
Where does the energy for photosynthesis come from
Sunlight although artificial light can be used in experiments
