ecology (p2)

Question 1

What is an ecosystem?

Answer 1

The interaction of a community of living organisms with the non-living parts of their environment.

Question 2

What do plants compete for in a community?

Answer 2

light,
space,
water,
mineral ions from the soil

Question 3

What do animals complete for in a community?

Answer 3

mates,
territory
food

Question 4

What is interdependence?

Answer 4

Species in a community depend of each other species for food, shelter, pollination, seed dispersal, etc. If one species is removed it can affect the whole community.

Question 5

What is a stable community?

Answer 5

A community where all the species and environmental factors are in balance so that population sizes remain fairly constant.

Question 6

What are the abiotic factors that can affect a community?

Answer 6

light intensity,
temperature,
moisture levels,
soil pH and mineral content,
wind intensity and direction,
carbon dioxide levels for plants,
oxygen levels for aquatic animals.

Question 7

What are the biotic factors that affect a community?

Answer 7

availability of food,
new predators arriving,
new pathogens,
one species outcompeting another so the numbers are no longer sufficient to breed

Question 8

What does abiotic mean?

Answer 8

Non-living

Question 9

What does bioitic mean?

Answer 9

Living

Question 10

What is an adaptation?

Answer 10

A feature that enables an organism to surve in the conditions which they normally live.

Question 11

What is an extremophile?

Answer 11

An organism that lives in an extreme environment, such as one with high temepratures, high pressure or high salt concentration.

Question 12

What is a producer?

Answer 12

An organism which synthesises molecules. This is usually a green plant or alga which makes glucose by photosynthesis.

Question 13

What is a consumer?

Answer 13

An organism that eats other organisms in a food chain.

Question 14

What is the definition of prey?

Answer 14

Consumers (animals) that are killed and eaten

Question 15

What is the definition of a predator?

Answer 15

Consumers that kill and eat other animals

Question 16

How are quadrats used in random sampling?

Answer 16

1. Mark 1m intervals along the axes of the area you will sample
2. Using a random number generator to select coordinates, place the quadrat in the area
3. Count the number of organism, eg. daisies, in that quadrat
4. Repeat placing the quadrat & counting at least 10 times
5. Calculate the average number of organism in one quadrat
6. Using the area of the area, and the average, calculate an estimate for the number of organism in the area.

Question 17

What process removes carbon from the atompshere?

Answer 17

Photosynthesis

Question 18

What processes add carbon dioxide to the atmosphere?

Answer 18

Respiration,
combustion,
decomposition

Question 19

Why are microorganisms an important part of an ecosystem?

Answer 19

They help to cycle material through the ecosystem by decomposing dead organic matter. They release carbon dioxide to the atmosphere & mineral ions to the soil.

Question 20

What is biodiversity

Answer 20

The variety of all the different species of organisms in an ecosystem, or on earth.

Question 21

Why is it important to maintain a high level of biodiversity?

Answer 21

To maintain stable ecosystems by reducing the dependence of one species on another for food and shelter.

Question 22

What types of pollution can be present in water?

Answer 22

Sewage,
fertiliser,
toxic chemicals

Question 23

What types of pollution can be present in air?

Answer 23

Smoke and acidic gases

Question 24

What types of pollution can be present on land?

Answer 24

landfills & toxic chemicals

Question 25

What human activities reduce the amount of land available for other animals?

Answer 25

building, dumping waste, quarrying, farming

Question 26

What is a carbon sink?

Answer 26

An area where carbon is removed from the atmosphere and stored for a long period of time, such as peat or in a fossil fuel

Question 27

Why are peat bogs being destroyed?

Answer 27

to produce garden compost

Question 28

What are the negative effects of destroying peat bogs?

Answer 28

It reduces the habitat available for plants, animals and microorganisms that live there. Burning or decay of peat releases carbon dioxide inot the atmosphere.

Question 29

Why has large-scale deforestation occured in tropical areas?

Answer 29

to provide land for cattle and rice fields, to grow crops for biofuel

Question 30

What programs area there to help maintain biodiversity?

Answer 30

Breeding programs for endangered species, protection and regeneration of rare habitats, reintroduction of field margins and hedgerows in areas where farms grow only one type of crop, reduction of deforestation and carbon dioxide emissions by some governments, recycling