ecosystems

Question 1

what are the trophic levels?

Answer 1

the stages in a food chain

Question 2

what is a producer?

Answer 2

is at the bottom of all food chains,
always a plant or alga which can photosynthesize,
provide all the biomass for the food chain

Question 3

what do the arrows on a food chain represent?

Answer 3

the arrows show the transfer of biomass from one trophic level to another

Question 4

what is a primary consumer?

Answer 4

is the second stage of a food chain,
is a herbivore or omnivore,
they eat the producer

Question 5

what is a secondary consumer?

Answer 5

is a carnivore or omnivore,
eats the primary consumer,
there may be additional carnivorous consumers which would be called tertiary and quaternary

Question 6

what is an apex predator?

Answer 6

is at the top of the food chain,
have no predators
is a carnivore or omnivore

Question 7

how do you calculate the percentage transfer of biomass between trophic levels?

Answer 7

(energy transferred to biomass ÷ total energy supplied to organism) x 100

Question 8

what is biomass?

Answer 8

is the total mass of living material in an organism multiplied by the number of organisms

Question 9

what does the pyramid of biomass represent?

Answer 9

represents the relative amount of biomass at each trophic level in a food chain

Question 10

what is the rule about the transfer of biomass?

Answer 10

10% of energy from a given trophic level will be available to the next trophic level

Question 11

what does the inefficiency of the biomass transfer mean?

Answer 11

energy is wasted at each trophic level in a food chain, meaning less biomass and energy is passed on,
this progressive loss of energy usually means that there are fewer individuals at higher trophic levels

Question 12

what are the 4 reasons for the inefficient transfer of biomass?

Answer 12

1. not all the food is digested
2. mobile animals require a lot of energy for their movement, which means they have less energy for growth
3. warm-blooded animals need to use energy to maintain a suitable body temperature.
4. some of the material is excreted

Question 13

what is a predator-prey graph?

Answer 13

they show the cyclical nature of predator-prey populations in stable communities
an increase in prey means there is more food for the predators so both population increase
an increase of predators means more prey is eaten so the prey population decreases and then so does the predator

Question 14

what is mutualism?

Answer 14

when both species in this relationship benefit

Question 15

what is parasitism?

Answer 15

when one organism benefits from the relationship but the other is harmed

Question 16

what is biodiversity?

Answer 16

is the variety of all the plant and animal life in the world or in a particular habitat

Question 17

what does the industrial revolution have to do with biodiversity?

Answer 17

since the industrial revolution, humans have done things that have caused a severe decline in biodiversity like sewage and litter

Question 18

what is waste management?

Answer 18

as the human population increases, the volume of waste and pollution produced also increases

Question 19

what is intraspecific competition?

Answer 19

competition between members of the same species

Question 20

what is interspecific competition?

Answer 20

competition between members of different species

Question 21

what 3 human activities impact biodiversity?

Answer 21

1. overuse of fertilisers can cause eutrophication and reduce biodiversity
2. fish farming can reduce biodiversity
3. Introduction of non-indigenous species can reduce biodiversity

Question 22

what is eutrophication?

Answer 22

excessive nutrients in a body of water due to run-off from the land, which causes a dense growth of plant life

Question 23

what are non-indigenous species?

Answer 23

are species introduced outside their natural habitat through countries trading