SB9

Question 1

what is an ecosystem

Answer 1

a community of living organisms interacting with each other and their non-living environment within a specific area

Question 2

what is a population

Answer 2

all organisms of one species in an area

Question 2

what is a habitat

Answer 2

place where an organism lives

Question 3

what is a community

Answer 3

all populations in an area

Question 3

what is a producer

Answer 3

makes own food by photosynthesis

Question 4

energy source for most ecosystems

Answer 4

sunlight

Question 5

what is a consumer

Answer 5

eats other organisms

Question 6

what is a predator

Answer 6

hunts other animals

Question 7

what is a prey

Answer 7

eaten by predators

Question 8

what happens to energy every trophic level

Answer 8

it is lost to surroundings as heat, waste etc

Question 9

examples of abiotic factors

Answer 9

temperature, light, water, pH, minerals

Question 10

effect of temperature on communities

Answer 10

extremes reduce population size

Question 11

purpose of quadrat

Answer 11

estimate population size of plants

Question 12

purpose of transect

Answer 12

study distribution of organisms along a line

Question 13

how to calculate population from quadrat

Answer 13

mean number per quadrat × total area ÷ quadrat area

Question 14

effect of competition

Answer 14

reduces population size of competing species

Question 14

examples of biotic factors

Answer 14

animals, plants, microorganisms

Question 15

indicator species for clean water

Answer 15

mayfly larvae, stonefly nymphs

Question 16

indicator species for polluted water

Answer 16

rat-tailed maggot, bloodworm

Question 17

method to assess air pollution

Answer 17

lichen diversity

Question 18

what is parasitism

Answer 18

one organism benefits, one is harmed

Question 19

example of parasitism

Answer 19

tapeworm in intestine

Question 20

what is mutualism

Answer 20

both organisms benefit

Question 21

example of mutualism

Answer 21

bees pollinating flowers

Question 22

what is biodiversity

Answer 22

variety of species, habitats, and genes in an ecosystem

Question 23

why is biodiversity important

Answer 23

stabilises ecosystems, provides food, medicine, and ecosystem services

Question 24

methods to preserve biodiversity

Answer 24

protected areas, breeding programs, reforestation, legal protection

Question 25

example of legislation

Answer 25

CITES – protects endangered species

Question 26

what does biodiversity include

Answer 26

species, habitat, and genetic variety

Question 27

what is food security

Answer 27

reliable access to sufficient, safe, nutritious food

Question 28

main processes of the water cycle

Answer 28

evaporation, condensation, precipitation, infiltration, transpiration

Question 28

factors reducing food security

Answer 28

pests, climate change, overfishing, war, disease

Question 28

role of plants

Answer 28

transpiration returns water to the atmosphere

Question 28

main processes of the carbon cycle

Answer 28

photosynthesis, respiration, decomposition, combustion, fossilisation

Question 29

role of decomposers

Answer 29

break down dead matter → carbon returns to soil or atmosphere

Question 30

key processes of the nitrogen cycle

Answer 30

nitrogen fixation, nitrification, assimilation, ammonification, denitrification

Question 31

importance of nitrogen

Answer 31

used to make amino acids, proteins, nucleic acids

Question 32

factors affecting decomposition rate

Answer 32

temperature, oxygen, moisture, number of decomposers

Question 33

effect of higher temperature

Answer 33

increases rate of decomposition

Question 34

effect of anaerobic conditions

Answer 34

slows decomposition

Question 35

what does decomposition do

Answer 35

returns nutrients to the ecosystem

Question 36

how is nitrogen recycled

Answer 36

by bacteria