Unit 4 Ecology

Question 1

Autotrophs

Answer 1

organisms that produce their own food

Question 2

Heterotrophs

Answer 2

organisms that feed on other organisms

Question 3

Consumers

Answer 3

heterotrophs that feed on living organisms by ingestion

Question 4

Detritivores

Answer 4

heterotrophs that obtain organic nutrients from detritus by internal digestion

Question 5

Saprotrophs

Answer 5

heterotrophs that obtain organic nutrients from dead organisms by external digestion

Question 6

Species

Answer 6

organism that have common characteristics which are capable of producing fertile offspring

Question 7

Population

Answer 7

a group of organisms of one species that interbreed and line in the same place at the same time

Question 8

Community

Answer 8

formed by populations of different species living together and interacting with each other

Question 9

ecosystem

Answer 9

a community and its interactions with the abiotic environment

Question 10

mesocosms

Answer 10

experimental systems that can be set up to study natural environments under controlled conditions

Question 11

pyramids of energy

Answer 11

are diagrams that represent that amount of energy converted to biomass at the different trophic levels

Question 12

How is heat lost

Answer 12

through respiration

Question 13

Outline the energy flow through a food web

Answer 13

autotrpohs are producers that convert light energy into chemical energy that is used by the plant and lost as heat to the surroundings through respiration. Primary consumers consume plants and only 10% of their energy is passed on to the next trophic level as energy is lost as heat. Energy is lost as not all of the plant is eaten or digested

Question 14

Carbon Sink

Answer 14

is a reserve of carbon

Question 15

carbon flux

Answer 15

the transfer of carbon from one carbon sink to another

Question 16

peat

Answer 16

organic matter that is not fully decomposed due to acidic or waterlogged soils

Question 17

fossil fuels

Answer 17

partially decomposed organic matter from past geological eras that accumulate in porous rocks

Question 18

limestone

Answer 18

a rock composed of calcium carbonate, is mainly formed from sediments containing the remains or marine organisms such as corals and molluscs

Question 19

greenhouse gases

Answer 19

those that produce the greenhouse effect

Question 20

greenhouse effect

Answer 20

is the process by which the Earths surface is warmed due to entrapment of the radiation re-emitted by the Earth as long-wave radiation

Question 21

Explain the interaction of short and long wave radiation with greenhouse gases in the atmosphere

Answer 21

Greenhouse gases include gases such as CO2, methane, water vapour… Short wave radiation from the rays of the sun penetrate these gases in the atmosphere, reaching the surface of the Earth and thus delivering heat energy. However when they reflect from the surface, they become long-wave radiation which is absorbed by the gases and reflected back to the earth or trapped in the atmosphere causing the earth to become warmer.