B16 organisms and ecosystems

Question 1

what is the source of energy for most communities of living organisms

Answer 1

light from the sun

Question 2

what are plants and algae

Answer 2

producers

Question 3

what is biomass

Answer 3

the mass of one animal or plant species in a food chain or web

Question 4

what are producers

Answer 4

things that produce there own food from photosynthesis`

Question 5

how can feeding relationships be presented

Answer 5

food chains

Question 6

what are primary consumers

Answer 6

animals that eat producers (plants)

Question 7

examples of primary consumers

Answer 7

sheep, hippos, crabs or caterpillars

Question 8

what are secondary consumers

Answer 8

animals that eat primary consumers

Question 9

examples of secondary consumers

Answer 9

lions, foxes, seals or eagles

Question 10

what are tertiary consumers

Answer 10

animals that eat secondary consumers

Question 11

what are consumers that eat other animals calles

Answer 11

predators

Question 12

what are consumers that are eaten called

Answer 12

prey

Question 13

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

Answer 13

they rise and fall in a linked cycle

Question 14

what are the producers of the biomass for earth

Answer 14

photosynthetic organisms

Question 15

describe the cycle for predator and prey populations

Answer 15

1 if plenty of food is available prey reproduce successfully so numbers increase
2 As prey numbers go up, predators have more food so their numbers begin to go up
3 the high number of predators eat all the prey leading to prey population falling
4 with less prey, predator numbers begin to drop
5 with less predators, prey numbers go up and the cycle repeats itself.

Question 16

what are decomposers

Answer 16

a group of organisms that break down waste and dead animals and plants

Question 17

what chemicals make up organisms

Answer 17

Carbon, Oxygen, Nitrogen and Hydrogen

Question 18

examples of decomposers

Answer 18

bacteria and fungi

Question 19

how are organisms decomposed

Answer 19

maggots and worms start the decay cycle by eating dead plants and animals and produce waste material. Bacteria and fungi then digest everything and use the nutrients to release Carbon Dioxide, water and minerals as waste products.

Question 20

What do decomposes do

Answer 20

clean up the environment

Question 21

what does decay do

Answer 21

it returns Carbon to the atmosphere.

Question 22

what are the main stages to the decay cycle

Answer 22

1 plant eaten by consumer
2 death/excretion
3 decomposes break down waste materials and dead bodies
4 Carbon dioxide in air and minerals in soil
5 Carbon dioxide into plants via photosynthesis Minerals into plants through roots

Question 23

what are the main stages to the water cycle

Answer 23

condensation
precipitation
evaporation
transpiration
respiration
percolation

Question 24

what is percolation

Answer 24

where water trickles through gaps in soil and rocks

Question 25

what is transpiration and respiration

Answer 25

where water gets into atmosphere directly from pants and animals.

Question 26

what are carbon sinks

Answer 26

a place where carbon is locked up

Question 27

examples of carbon sinks

Answer 27

coal, oil, gas, dissolved in lakes and oceans

Question 28

how is Carbon taken out of the environment

Answer 28

photosynthesis

Question 29

how is carbon returned to the atmosphere

Answer 29

respiration in animals and decomposers

Question 30

what is combustion

Answer 30

the burning of fossil fuels and wood

Question 31

how does combustion add carbon to the atmosphere

Answer 31

fossil fuels and wood contain locked up Carbon, and when burnt, this carbon is released back into the atmosphere.

Question 32

equation for combustion

Answer 32

fossil fuel/wood + oxygen –> Carbon dioxide +water

Question 33

describe the carbon cycle

Answer 33

• animals eat plants
• animals and plants die leaving organic materials in dead organisms
• decay and decomposition releases co2 into air when decomposers respire
• carbon compounds in fossil fuels are burnt releasing co2 into air
• photosynthesis removes co2 from environment
• respiration from plants and animals returns CO2 to atmosphere

Question 34

what is causing global warming

Answer 34

levels of carbon dioxide in the atmosphere have increased.

Question 35

what do scientists fear about the carbon cycle

Answer 35

it may not maintain atmospheric carbon dioxide at a level that will maintain long term human survival