!! 4.7.2

Question 1

what are predators

Answer 1

consumers that kill or eat other animals

Question 2

why does the number of prey fluxuate

Answer 2

based on their surroundings

e.g in a milder winter there’s more food so more survive

Question 3

what happens to the number of prey and predators in a stable community

Answer 3

the number of both falls and rises

Question 4

which organisms are the producers of biomass for life on earth

Answer 4

photosynthetic organisms

Question 5

what do all food chains begin with

and a real life example

Answer 5

a producer which synthesises molecules

usually a plant or algae which makes glucose by photosynthesis

Question 6

what can be represented by food chains

Answer 6

feeding relationships in communities

Question 7

what is a community

Answer 7

every individual from every species in a habitat

Question 8

what is the most significant effect on biodiversity from human population increase

Answer 8

reduction in habitat

Question 9

3 ways humans reduced habitat effecting biodiversity

Answer 9

buildings

farming

dumping waste

Question 10

how have buildings effected biodiversity on earth

Answer 10

growing population needs somewhere to live

quarrying for building materials massively increased

leading to habitat destruction

Question 11

how has farming effected biodiversity on earth

Answer 11

more and more land devoted to farming

e,g more and more deforestation of the rainforest for cattle ranches for burgers

Question 12

how has the growing human population dumping waste affected Earth’s biodiversity

Answer 12

more and more consumption leads to more and more landfill

Question 13

increase of human population effect on raw materials

Answer 13

raw materials being used up rapidly such as coal, oil and wood

Question 14

which 3 places can pollution occur

Answer 14

water

air

land

Question 15

how does pollution occur in water

Answer 15

fertiliser, runs off farms into river and streams

sewage, pumped into rivers and streams

toxic chemicals

Question 16

how does pollution occur on land

Answer 16

landfill

pesticides

herbicides

toxic chemicals

may all be washed into water

Question 17

how does pollution occur in the air

give an example

Answer 17

smoke

acidic gases

e.g sulfur dioxide dissolves in rain, forms sulfuric acid and then becomes acid rain

Question 18

how does climate change have an impact on biodiversity

Answer 18

changing distribution - organisms moving to different parts of the world

plants blooming earlier

Question 19

why may removing one species from an ecosystem make it unstable

Answer 19

interdependence between different species

one species may rely on another species for services such as food, shelter, pollination, and seed dispersal.

removing one species from an ecosystem could remove a key predator or prey.

either increasing or reducing population size

Question 20

what is a transect

Answer 20

a line defined using a tape measure

Question 21

where are transects usually placed

Answer 21

across a changing habitat

e.g across a rocky shore

Question 22

basic transect method

Answer 22

use tape measure to produce transect across (where you’re measuring)

place quadrats along transect at appropriate intervals

measure presence of each species and how many of each there are

repeat 10 times

Question 23

what can transects be used to investigate

Answer 23

the effect of a factor on the distribution of a species

Question 24

what is a quadrat

Answer 24

a square frame that can be used to estimate population size

Question 25

calulation for estimated population size using qaudrats

Answer 25

no. individuals counted × area sampled / total survey area

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