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Question 1

What is a species?

Answer 1

A group of organisms that can interbreed and produce fertile offspring

Question 2

What is a habitat?

Answer 2

The environment in which a species normally lives or the location of a living organism

Question 3

Population

Answer 3

A group of organisms of the same species who live in the same area at the same time

Question 4

What is a community?

Answer 4

A group of populations of the same area living and interacting with each other

Question 5

What is an ecosystem?

Answer 5

A community and its abiotic environment

Question 6

What is ecology?

Answer 6

The study of relationships between living organisms and their environment

Question 7

What is an autotroph?

Answer 7

An organism that synthesises its organic molecules from simple inorganic molecules

Question 8

What are heterotrophs?

Answer 8

An organism that obtains organic molecules from other organisms

Question 9

What is a consumer?

Answer 9

An organism that ingests other organic matter that is living or recently killed

Question 10

What is a detrivore?

Answer 10

An organism that ingests non-living organic matter, a decomposer

Question 11

What is a Saprotroph?

Answer 11

An organism that lives in or in non-living organic matter, secreting digestive enzymes and absorbing products of digestion

Question 12

What is a good chain?

Answer 12

A representation of the relationships between organisms based on their diet

Question 13

What does a food web show?

Answer 13

How food chains are linked together in to more complex feeding relationships

Question 14

How is sunlight converted to chemical energy?

Answer 14

Sunlight is trapped by the protein chlorophyll through photosynthesis and converted to chemical energy

Question 15

Why is there energy loss between trophic levels?

Answer 15

Material is not consumed, which is used by saprophytes it respiration, but ultimately lost as heat to the environment, or it is assimilated and lost

Question 16

How much energy is assimilated at the next higher trophic levels?

Answer 16

10-20%

Question 17

What effect do extreme environments have impacted food chains?

Answer 17

In the Arctic, initial trapping of energy by producers is lower so the energy transfer to large predators is rare and food chains are shorter. In the rainforest trapping of energy by producers is more efficient so the food chains are longer and more complex

Question 18

What do pyramids of energy show?

Answer 18

• shows flow of energy from 2 trophic level to the next
• the decrease in shape as it goes upwards shows the gradual loss of energy
• shows biomass of organisms

Question 19

How do producers recycle nutrients?

Answer 19

Producers take organic molecules and convert them into organic compounds, which consumers feed on

Question 20

How are nutrients recycled?

Answer 20

• Producers take organic molecules and convert them into organic compounds
• consumers take in this organic matter by feeding and use it for growth
• decomposition begins when saprotrophic bacteria and fungi secrete extra cellular digestive enzymes into dead organisms, which are hydrolysed and reabsorbed by saprophytes

Question 21

What pools are carbon found in?

Answer 21

• biosphere
• oceans
• atmosphere
• sediments

Question 22

In which processes does carbon move between pools in?

Answer 22

• photosynthesis
• respiration
• feeding
• fossilisation
• combustion

Question 23

How does carbon move in photosynthesis?

Answer 23

It moves by terrestrial and algae in which atmospheric and dissolved carbon is removed and fixed as carbon compounds, such as carbohydrates, lipids and proteins

Question 24

How does carbon move in feeding?

Answer 24

Carbon of organic molecules move from one link in the food chain to another

Question 25

How is carbon moved in fossilisation?

Answer 25

Carbon as organic molecules, becomes trapped in sediment as coal, gas and oil

Question 26

How is ATP produced?

Answer 26

By cell respiration

Question 27

What type of reaction is cell respiration?

Answer 27

Exothermic

Question 28

What happens as ATP is produced in cell respiration?

Answer 28

Carbon compounds are oxidised but are not immediately usable but ATP is as it is used in cell activities

Question 29

What is the mean concentration of CO2 in the atmosphere?

Answer 29

0.039%

Question 30

What happens to CO2 I’m solution?

Answer 30

- CO2 is soluble in water - it either remains as dissolved has or combines with water to form carbonic acid - this can dissociate to form hydrogen and hydrogen carbonate ions (H+ and HCO3- - this reduces the pH of water

Question 31

How is CO2 absorbed?

Answer 31

It diffuses from atmosphere or water into autotrophs and photosynthesis reduces the concentration of CO2 in autotrophs, setting up a concentration gradient between the biotic and the abiotic. In leaves CO2 diffuses through the stomata on the underside of leaves. In aquatic plants the entire of the leaves and stem is permeable to CO2.

Question 32

How is methane produced?

Answer 32

It is produced from organic matter in anaerobic conditions by methanogenic archaens and diffuses into the atmosphere

Question 33

What is the concentration of methane in the atmosphere?

Answer 33

1.7-1.85 mmpm

Question 34

How is methane removed from the atmosphere?

Answer 34

Molecules of methane persist in the atmosphere for 12 years and and naturally oxidised in the stratosphere, and monatomic oxygen and highly reactive hydroxyl radicals are involved.

Question 35

How is peat formed?

Answer 35

In some environments water is unable to drain from soil producing anaerobic conditions that saprotrophs can’t survive in, and therefore there is no decomposition and acidic conditions develop.

Question 36

What percentage of the earths surface is peat?

Answer 36

3%

Question 37

How are fossils formed in limestone?

Answer 37

- animals, such as reef building corals and molluscs have hard parts composed of calcium carbonate - when dead the decompose quickly - in acidic conditions, calcium carbonate dissolves away, in neutral or alkaline conditions it is stable and deposits form in the sea bed - in shallow, tropical seas, calcium carbonate is deposited by precipitation in water on limestone rock and animals are visible as fossils

Question 38

What percentage of all sedimentary rock is limestone?

Answer 38

10%

Question 39

What is the enhanced greenhouse effect?

Answer 39

The idea that humans are increasing the levels of CO2 and other greenhouse gases, which leads to climate change

Question 40

What are greenhouse gases?

Answer 40

Gas molecules in our atmosphere with 3 or 4 more atoms that can capture outgoing infrared energy and warm the planet

Question 41

What do increased greenhouse gases mean?

Answer 41

More infared light will be absorbed and scattered and retained as heat

Question 42

What does the precautionary principle say?

Answer 42

It says that if the effects of a human induced change that would be very large then those responsible must prove that it will do no harm before proceeding. If it is not proven that no harm will come, it must not go ahead

Question 43

What are effects of the greenhouse effects?

Answer 43

- higher frequency and intensity of droughts - flooding due to higher rainfall - declines in food production - increased disease as higher temperature causes more pathogens - more extreme weather - loss of biodiversity

Question 44

What are consequences of the greenhouse effect on arctic ecosystems?

Answer 44

- detritus is released from a permafrost state which leads to huge releases of methane and CO2, which was previously locked away - more areas with soul rich in humus are formed, causing more plant life to grow, absorbing radiant heat energy and contribute to global warming - Extensive flooding in low lands - there is a greater number of predators on expanding vertebrate populations