B21 Energy flow in ecosystems

Question 1

the principal source of energy input to biological systems

Answer 1

the sun

Question 2

food chain

Answer 2

a chart showing the flow of energy from one organism to the next beginning with a producer

Question 3

food web

Answer 3

a network of interconnected food chains showing the energy flow through part of an ecosystem

Question 4

producer

Answer 4

an organism that makes its own organic nutrients, usually using energy from sunlight, through photosynthesis

Question 5

consumer

Answer 5

organism that gets its energy by feeding on other organisms

Question 6

herbivore

Answer 6

an animal that gets its energy by eating plants

Question 7

carnivore

Answer 7

an animal that gets its energy y eating other animals

Question 8

decomposer

Answer 8

an organism that gets its energy from dead or waste organic matter. they excrete enzymes onto the material and consume it. They help assist in decay

Question 9

ecosystem

Answer 9

a unit containing all of the organisms and their environment interacting together, in a given area

Question 10

trophic level

Answer 10

the position of an organism in a food chain or food web

Question 11

why is not all energy passed on from one trophic level to the next?

Answer 11

1) not all material can be digested by the consumer/ not all is consumed
2) part of the biomass is used in respiration, movement etc
3) much energy is lost as heat

Question 12

examples of decomposers

Answer 12

bacteria, fungi

Question 13

detrivores

Answer 13

they digest dead/ waste matter internally and assist in decay by breaking it up into smaller pieces/ increasing surface area

Question 14

Detrivore examples

Answer 14

worms, beetles, termites

Question 15

conditions for fast decomposition and nutrient cycling

Answer 15

1) moist environment
2) oxygen
3) warmth

Question 16

Carbon cycle

Answer 16

the constant recycling of carbon between living things and the environment

1) CO2 removed from air by plants in photosynthesis- used to make carbohydrates, proteins, fats
2) plants eaten by animals
3) plants and animals respire to release CO2 back into air
4) plants and animals die and bodies decomposed. decomposers respire to release CO2.

^humans combust fossil fuels to release CO2- affecting carbon cycle

Question 17

Carbon sink

Answer 17

a forest, ocean or natural environment that can absorb CO2 from the atmosphere

Question 18

greenhouse effect

Answer 18

when energy from the sun passes through the atmosphere and is reflected back to the earth. Due to the greenhouse gases, some energy is absorbed and re-emitted, warming the Earth’s atmosphere

Question 19

Human activities that increase greenhouse gases

Answer 19

1) deforestation- removing carbon sinks
2) combustion of fossil fuels- releases CO2
3) increasing agriculture- releases methane