Paper 1 - Section B, Ecosytems

Question 1

What are producers

Answer 1

Producers convert energy from the environment into sugars. For example, plants that convert energy from the sun by photosynthesis

Question 2

What are consumers

Answer 2

Consumers get energy from (eg a pond snail gets its energy from eating plants)

Question 3

What are decomposers

Answer 3

Decomposers break down plant and animal material and return nutrients to the soil eg bacteria and fungi

Question 4

What is a food chain

Answer 4

A food chain shows direct links between producers and consumers in a simple line

Question 5

What is a food web

Answer 5

A food web shows all the connections between producers and consumers in a rather complex way

Question 6

What are some examples of abiotic factors in a freshwater pond ecosystem

Answer 6

• solar radiation
• temperature
• depth of water

Question 7

What are some examples decomposers in a freshwater pond ecosystems

Answer 7

Bacteria and fungi

Question 8

What are some examples of consumers in a freshwater pond ecosystem

Answer 8

• frog
• duck
• pond snail

Question 9

What are some examples of producers in a freshwater pond ecosystem

Answer 9

Grass, algae and bushes

Question 10

What would happen if the pond became polluted

Answer 10

Plants and animals would die and this could cause a knock-on effect up the food chain and effect the whole thing

Question 11

What would happen if an animal in a food chain went extinct

Answer 11

Its prey would no longer be hunted and its predator would no longer have any food and can cause a chain of reactions effecting the ecosystem. For example, the prey would overpopulate as there would be nothing hunting it

Question 12

What are the 5 habitats within a freshwater pond ecosystem

Answer 12

1. Above the surface
2. The surface
3. Pond margin
4. Midwater
5. Pond bottom

Question 13

Describe the surface within a freshwater pond ecosystem

Answer 13

• plenty of oxygen
• animals breathe through gills, skin or lungs

Question 14

Describe above the surface in a freshwater pond ecosystem

Answer 14

• birds and animals breathe oxygen
• food found in or in water or in the margins

Question 15

Describe the pond margin in a freshwater pond ecosystem

Answer 15

• plenty of oxygen, light and shelter for plants and insects for small animals to eat

Question 16

Describe midwater in a freshwater pond ecosystem

Answer 16

• animals breathe through gills/skin
• fish are the main predators
• food found on the surface or in pond

Question 17

Describe the pond-bottom in a freshwater pond ecosystem

Answer 17

• little oxygen or light
• plenty of shelter and food
• decomposers and scavengers live here

Question 18

What is an example of a food chain in a freshwater pond ecosystem

Answer 18

Solar energy —> algae (producer) —> mayfly (consumer) —> fish (consumer)—> heron (consumer) —> pond snail (decomposer)

Question 19

What does it mean if an ecosystem is said to be in equilibrium

Answer 19

All the components of an ecosystem are in balance

Question 20

What are natural causes of change in an ecosystem

Answer 20

• extreme weather events (eg flooding)
• volcanic eruptions
• climate change

Question 21

What are human causes of change in an ecosystem

Answer 21

• ponds may be drained for farming
• woods cut down
• urbanisation

Question 22

How does climate control the distribution of tropical rainforest ecosystems

Answer 22

• sunlight, temp and rainfall can affect the type and number of plants that can grow
• TRF contain greatest variety and density of plant growth because they are located in climate zones where temperatures are warm and wet
• warm due to being near the equator, and wet because low pressure zone created by rising warm air at the equator