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Flashcards in Unit 3 Deck (72)
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1

What is a niche?

The role an organism plays within a community

2

What are the factors that determines an organisms niche?

Habitat, feeding level, when active, interaction with other organisms

3

What are biotic factors?

Factors related to living things

4

What are abiotic factors?

Non-living or physical factors

5

Give an example of a biotic factor

Competition for food, space, mates. Number of predators. Disease. Grazing

6

Give an example of abiotic factors

Temperature, humidity, pH, light intensity, rainfall, wind

7

What could over grazing lead to?

Plant species being destroyed

8

What is predation?

The eating of one organism from another

9

What do predators keep down the numbers of?

Their prey

10

What is biomes?

The different regions of our planet as distinguished by their similar climate, fauna and flora

11

What can biomes be influenced by?

Temperature and rainfall

12

How can energy be lost in an ecosystem?

Heat movement, trapped in waste

13

In a food chain how much of the energy is lost between each animal?

90%

14

When an animal or plant dies what breaks it down?

Decomposers

15

What is a pyramid of biomass?

Represents the mass of each feeding level in a food chain

16

Which type of pyramid is the most accurate?

Pyramid of energy

17

Why do living things need nitrogen?

To form proteins

18

What can farmers do if the soil is low in nitrates?

They add it in the form of fertilisers

19

What is nitrification?

Bacteria converting ammonium compounds into nitrites then nitrates

20

What is denitrification?

Bacteria deprived soil of nitrogen by releasing gas into the air

21

What is nitrogen fixation?

Bacteria absorb and 'fix' nitrogen into nitrates for plants to absorb

22

What is intra specific competition?

Competition between members of the same species

23

What is the definition of a community?

All living things in an ecosystem

24

What is inter specific competition?

Competition between members of different species

25

What does competition help prevent?

Population of animal and plants becoming too large

26

What can competition be for?

Space, mates, food, water, light, shelter

27

What would plant in a large forest compete for?

Light, water, CO2, nutrients

28

Name two sampling techniques for biotic factors

Quadrat and pitfall trap

29

How does a quadrat work?

Laid out randomly on ground, plants and animals are counted

30

How does a pitfall trap work?

Animals fall into container