food chains, food webs, pyramids of biomass and pyramids of energy transfer

Question 1

what is a community?

Answer 1

the populations of all the species present in an ecosystem at a particular time

Question 2

how do the species in a community interact with eachother?

Answer 2

feeding on eachother- this allows nutrients to be recycled
competition for resources- e.g. food, mates, resting sites, light, mineral ions
using abiotic factors- e.g. absorbing mineral ions from the soil and using water

Question 3

what do food chains show?

Answer 3

feeding relationships in an ecosystem

Question 4

what do the arrows show?

Answer 4

means “is eaten by”
they show the direction that energy and biomass moves from the species that is eaten to the animal that eats it

Question 5

what are these stages in a food chain/ web called?

Answer 5

trophic levels

Question 6

what will food chains always begin with?

Answer 6

a producer

Question 7

how does energy not get passed/gets lost?

Answer 7

few organisms eat the full organism e.g. bones, hair etc

Question 8

how is the majority of energy lost/ not passed on?

Answer 8

making waste products e.g. urine
movement
heat
undigested waste (faeces)

Question 9

what is a food web?

Answer 9

a network of interconnected food chains

Question 10

what are food webs useful for?

Answer 10

understanding the links between the species in a community

Question 11

what is a decomposer?

Answer 11

bacteria and fungi that get their energy from feeding off dead and decaying organisms and undigested waste (such as faeces) by secreting enzymes to break them down

Question 12

what do food webs also show?

Answer 12

interdependence

Question 13

what do most of the changes of plants and animals occur by?

Answer 13

human impact- overharvesting of food species or by the introduction of foreign species to a habitat

Question 14

what do food pyramids show?

Answer 14

shows how many organisms we are talking about at each level of a food chain

Question 15

what does the width of the box indicate?

Answer 15

the number of organisms at that trophic level

Question 16

what do ecological pyramids represent?

Answer 16

the relative amounts of organisms at each trophic level

Question 17

what does a pyramid of biomass show?

Answer 17

shows how much mass the creatures at each level would have without including all their water inside the organism (their dry mass)

Question 18

what do pyramids of biomass give a good idea of?

Answer 18

the quantity of the plant or animal material at each level of a food chain and therefore are a better way of presenting interdependence within the food chain

Question 19

what do pyramids of energy show?

Answer 19

illustrate the amount of energy contained within the biomass of individuals within different trophic levels

Question 20

what does the area of each box in a pyramid of energy represent?

Answer 20

the quantity of energy

Question 21

why do these pyramids always have a large base?

Answer 21

due to the large amount of energy contained within the pyramid of biomass