Communities/ Ecosystems

Question 1

What is an ecosystem?

Answer 1

The interaction between a community of living organisms and their environment.

Question 2

What is a community?

Answer 2

Two or more populations of organisms.

Question 3

‘As you move outwards from a tree there will be more plant growth.’
Explain why the students thought their hypothesis would be correct.
(3)

The leaves _______________ near the tree so there is more light as you __________________ for ___________________.

Which produces more __________ for ____________.

Answer 3

block light
move outwards
photosynthesis

glucose
growth

Question 4

Give three reasons why a strawberry decays after 3 days of storage:

1.
2.
3.

Answer 4

1. It was stored at a higher temperature.
2. It was stored in more moisture.
3. The storage contained more microorganisms that cause decay.

Question 5

What 4 factors do plants compete for in an ecosystem?
1.
2.
3.
4.

Answer 5

1. Light.
2. Space.
3. Water.
4. Minerals.

Question 6

What 4 factors do plants compete for in an ecosystem?
1.
2.
3.

Answer 6

1. Food.
2. Mates.
3. Territory.

Question 7

What is intraspecific competition?

Answer 7

Competition between organisms within the same species.

Question 8

What is a stable community?

Answer 8

A community where the size of the populations of all species remain relatively constant over time.

Question 9

What are the 7 abiotic factors that affect the abundance and distribution of plants?

Answer 9

1. Light intensity.
2. Temperature.
3. Moisture levels.
4. Soil pH content.
5. Soil mineral content.
6. Wind intensity/ direction.
7. Carbon dioxide concentration.

Question 10

What is interdependence?

Answer 10

The fact that organisms in an ecosystem are dependent upon each other to survive.

Question 11

Bacteria and fungi are _______________ that ______________ dead matter by __________________ onto the matter and ___________________________________.

Answer 11

decomposers
break down
releasing enzymes
consuming the broken down substances

Question 12

In the carbon cycle, what are the 3 main processes:
1.
2.
3.

Answer 12

1. Photosynthesis.
2. Respiration.
3. Combustion.

Question 13

How is carbon recycled into the growth of new leaves? (6)

Carbon compounds in dead leaves are ______________________________.

________________ respire and release carbon from leaves as ___________________.

Plants take in the released carbon dioxide for photosynthesis to ____________.

Glucose produced in photosynthesis is used to make ________________. Which are required for the ______________________.

Answer 13

broken down by microorganisms

Microorganisms
carbon dioxide

produce glucose

amino acids
growth of new leaves

Question 14

Describe the processes in the water cycle.
[6 marks]

Water _______________ from the __________________.

_________________ occurs so water evaporates from plants.

Water vapour ___________________________ into clouds.

Clouds can be transported far distances by the _________.

Then water can then fall as ________________.

This water can either ____________________ into the land surface during ______________.

Answer 14

evaporates
Earth’s surface

Transpiration

rises, then cools and condenses

wind

precipitation

run off or absorb
infiltration

Question 15

In a balanced ecosystem the numbers of predators and prey remain _________________.

Answer 15

fairly constant

Question 16

In a predator cycle,

1. The number of predators _____________ because there is more prey.
2. The number of prey ____________ because there are more predators.
3. The number of predators _____________ because there is less prey.

Answer 16

increases

decreases

decreases