Ecosystems and Material Cycles Flashcards Preview

1[GCSE Biology]1 > Ecosystems and Material Cycles > Flashcards

Flashcards in Ecosystems and Material Cycles Deck (21)
Loading flashcards...
1
Q

What is an individual?

A

A single organism

2
Q

What is population?

A

All the organisms of one species in a habitat

3
Q

What is a community?

A

All the organisms of different species living in a habitat

4
Q

What is an ecosystem?

A

A community of organisms along with the non-living (abiotic) conditions.

5
Q

What is interdependence?

A

When organisms depend on each other for things like food and shelter in order to survive and reproduce.

6
Q

What are the abiotic factors that affect communities?

A

Temperature
Amount of water
Light intensity
Levels of pollutants

7
Q

What are the biotic factors that affect communities?

A

Competition and Predation

8
Q

What is predation?

A

A biological interaction where a predator feeds on its prey.

9
Q

What is a quadrat?

A

A square frame enclosing a known area (eg 1m2) to compare how common an organism is in two sample areas.

10
Q

How do you work out the mean number of organisms?

A

Mean = total number of organisms
————————————-
number of quadrats

11
Q

What is a gradient?

A

When abiotic factors change across a habitat.

12
Q

What does a pyramid of biomass show?

A

How much the organisms at each level of a food chain would weigh if you put them together and how much energy there is at each stage in the food chain.

13
Q

What is a food chain?

A

A series of organisms each dependent on the next as a source of food.

14
Q

How do you calculate how much energy has been lost?

A

energy lost = energy available at previous level - energy transferred to next level.

15
Q

How do you calculate the efficiency of energy transfer?

A

efficiency = energy transferred to next level / energy available at previous level x 100

16
Q

How do you calculate the biomass lost / efficiency of biomass transfer?

A

Biomass transferred to previous level / energy available at previous level x 100

17
Q

What is biodiversity?

A

The variety of living organisms in an ecosystem.

18
Q

What is eutrophication?

A

An excess of nutrients in water which can lead to death.

19
Q

What is an indigenous species?

A

A species that naturally occurs in the area.

20
Q

What are the human impacts on biodiversity?

A

Eutrophication, Fish farming and introduction of non-indigenous species.

21
Q

What are the ways to maintain and conserve biodiversity?

A

Reforestation and conservation schemes (eg protecting a habitat and species)