F215:03:01 Ecosystems Flashcards Preview

F215:03 Ecosystems and sustainbility > F215:03:01 Ecosystems > Flashcards

Flashcards in F215:03:01 Ecosystems Deck (35):
1

What is an ecosystem?

All living organisms and non-living components in a specific habitat and their interactions

2

Give an example of a large and small scale ecosystem

Large: African grassland
Small: Pond

3

Define a habitat

a place where an organism lives

4

Define a population

all of the organisms of one species that live in one place at the same time and can breed together

5

What is a community?

all the populations of different species that live in the same place at the same time, and can interact with each other

6

What is a niche?

The role that each species plays in an ecosystem

7

Why is it almost impossible to define an organisms niche entirely?

Because organisms interact with both living and non-living things

8

What kind of things are included in a niche?

- How and what an organism feeds on
- What it excretes
- How it reproduces

9

Is it frequent for two species to occupy exactly the same niche in the same ecosystem?

No, it is impossible

10

How can living organisms in an ecosystem affect each other?

depending on their niche

11

Give 5 examples of biotic factors

food supply
predation
disease
parasitism
competition

12

Give 4 examples of abiotic factors

pH
Temperature
Soil type
light intensity

13

What is an abiotic factor?

factors that describe the effects of non-living components of an ecosystem

14

How are ecosystems made easier to understand?

As they are often described as being closed even though they do not have clear edges and it is difficult to draw a line around a group of organisms and say they only interact with each other.

15

Is population size stable in all ecosystems?

No, the size can rise/fall either very slightly or very noticeably.

16

Why are their fluctuations of population sizes within ecosystems?

Because the community of living things in an ecosystem interact with each other and with their physical environment.
And so any small changes in one can affect another

17

How does predators and prey affect each others population size within an ecosystem?

As if a predators population size goes up, then the population size of the prey will go down (because it is being eaten more frequently)

18

Give an example of how fluctuations in nitrogen levels in soil can alter the population size of plants growing there

Nitrogen-fixing plants would grow more successfully in nitrogen-deficient soil, but they would cause an increase in soil nitrogen levels so then this would help other plants to grow there aswell

19

How is matter constantly being recycled within an ecosystem and give two examples of this

nutrient cycles
e.g. nitrogen/carbon cycles

20

What is constantly recycled within an ecosystem and what is not?

matter is being constantly recycled
Energy is not constantly being recycled, it flows through the ecoystsem

21

Give an example of how energy flows through living organisms

Energy originates from sunlight
Captured by plant through photosynthesis and converted into chemical energy stored in molecules such as glucose, which are eaten by organisms
In respiration organic molecules e.g. glucose release energy

22

Give some examples of producers in the food chain

plants
photosynthetic organisms
algae
some bacteria

23

Why are plants, photosyntheic organisms, algae and some bacteria known as producers?

As they supply chemical energy to all other organisms

24

Give two examples of consumers

Animals/fungi

25

Give some examples of primary consumers

herbivores

26

give an example of a secondary consumer

carnivores which each herbivores

27

Give an example of tertiary consumers

Carnivores that eat other carnivores

28

Give 3 examples of decomposers

bacteria
fungi
some animals

29

Define a decomposer

living things that feed on waste materials/dead organisms

30

Define a consumer

Living organisms that feed off other living organisms

31

What is the difference between a consumer and a producer?

A producer is always autotrophic, converting light energy to chemical energy
Consumers gain energy and materials by eating other organisms

32

What is the difference between a habitat and a niche?

Habitat is where a species lives
a Niche is its role in an ecosystem

33

Describe the niche of a rabbit that lives in a field

Eats grass in the field
provides waste for decomposers to feed on
hence provides minerals for grass
reproduces with other rabbits
Digs burrows
provides food sources for foxes/birds of prey

34

Suggest why two species never occupy exactly the same ecosystem

If they occupy the same niche, they will compete
One will be better at competing than the other, and will survive and reproduce whereas the other will fail to reproduce and die out.

35

Thermal oceanic vents are examples of unusual ecosystems. There is no light on the ocean bed. What are the producers in this ecosystem and what form of energy do they use?

Producers: bacteria
Form of energy: Chemical energy