Organisms In The Environment

Question 1

What happens during photosynthesis

Answer 1

Light energy is transferred to chemical energy

Question 2

What is the equation for photosynthesis

Answer 2

Carbon dioxide + water—> (+light energy) glucose +oxygen

Question 3

What is released as a byproduct of photosynthesis

Answer 3

Oxygen

Question 4

What is the process for photosynthesis

Answer 4

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

Question 5

What is some of the glucose is converted into

Answer 5

Insoluble starch for storage

Question 6

What is the test for starch and what are its results

Answer 6

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

Question 7

When do plants grow best

Answer 7

When they have enough light, carbon dioxide and water and are kept at a suitable temperature

Question 8

Why do enzyme reactions slow down

Answer 8

When the temperature falls the enzymes work slower

Question 9

What will happen if there is too little carbon dioxide- give an example

Answer 9

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

Question 10

Name a limiting factor that would slow down the rate of photosynthesis

Answer 10

A lack of light

Question 11

What is a limiting factor

Answer 11

Anything which put a cap on the rate of a reaction

Question 12

What is the independent variable

Answer 12

The one being tested e.g. concentration of carbon dioxide

Question 13

What is a dependent variable

Answer 13

The one you measure in photosynthesis it is usually the volume of oxygen produced

Question 14

Name three substances used for storage in plants

Answer 14

Starch fats and oils

Question 15

What happens to the glucose produced by photosynthesis

Answer 15

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

Question 16

Why do plants and algal all cells need a supply of mineral ions such as nitrate ions

Answer 16

In order to produce protein. Plants absorb nitrate ions from the soil. Algae absorb nitrate ions from the water they live in

Question 17

What factors must be controlled in a greenhouse to improve plant growth

Answer 17

Light, temperature and carbon dioxide

Question 18

What is biomass

Answer 18

Biological material from living or recently living organisms

Question 19

What are physical factors that may affect the distribution of organisms

Answer 19

Temperature, availability of nutrients, amount of light, availability of water, availability of oxygen, availability of carbon dioxide

Question 20

Why are there so few animals living in very cold regions such as the Arctic

Answer 20

Very few plants grow there – those that do are very small, so there is little food for animals

Question 21

What is a quadrat

Answer 21

A square frame which may be divided into a grid

Question 22

What is a quadrat used for

Answer 22

A quadrat is used for estimating the distribution of living things in their natural environment

Question 23

What is random quadrat or a transect

Answer 23

A quadrat

Question 24

What is a transect

Answer 24

A measured line marked between two points on which a quadrat can be placed at equal distances apart.

Question 25

How can you make sure an investigation is valid

Answer 25

Only the independent variable Should affect the results all other variables must be controlled

Question 26

Why is it necessary to check the results

Answer 26

To ensure your results are reproducible

Question 27

Why is it important to get the right sample size

Answer 27

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

Question 28

Why would there be little point in heating the greenhouse on a summers day

Answer 28

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

Question 29

Why is it difficult to be sure an investigation in outdoor habitats is valid

Answer 29

There are so many variables which are difficult to control

Question 30

What is meant by the term reproducible results

Answer 30

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

Question 31

Where does the energy for photosynthesis come from

Answer 31

Sunlight although artificial light can be used in experiments