Ecology

Question 1

What does population mean?

Answer 1

All the organisms of one species living in a habitat

Question 2

What does community mean?

Answer 2

The populations of different species living in a habitat

Question 3

What does a stable community mean?

Answer 3

A community in which all species and environmental factors are in balance, so the population sizes are roughly constant

Question 4

What does ecosystem mean?

Answer 4

The interaction of a community of organisms and the parts of their environment that are non-living

Question 5

What does adaptation mean?

Answer 5

A feature that enables an organism to survive in the conditions of its normal habitat

Question 6

What does interdependence mean?

Answer 6

Each species in a community depending upon other species for things eg, pollination, food, shelter or seed dispersal

Question 7

What factors affect communities?

Answer 7

Light intensity. Moisture level
New predators. Competition - plants, light space minerals, water
Food availability. - animals, food, mates, territory
O2 levels (aquatic mammals)
New pathogens
Temperature
Wind intensity and direction
CO2 levels (plants)
Soil pH and mineral content

Question 8

What are the 3 types of adaptations?

Answer 8

1: structural - eg, a white winter coat helps to camouflage against the snow
2: behavioural - eg, some birds migrate to warmer climates in winter
3: functional - eg, some animals lower their metabolism and hibernate over winter

Question 9

What are extremophiles?

Answer 9

Organisms that are adapted to live in extreme conditions such as high temperature, high pressure or high salt concentration (eg, bacteria in deep sea vents)

Question 10

What is a producer?

Answer 10

A plant or alga that makes glucose by photosynthesis. All food chains start with a producer.

Question 11

What is a primary consumer?

Answer 11

An animal that eats producers and may be eaten by secondary consumers

Question 12

What is a secondary consumer?

Answer 12

An animal that eats primary consumers and may be eaten by tertiary consumers

Question 13

What is a predator?

Answer 13

A consumer that kills and eats other animals (prey)

Question 14

What is a biomass?

Answer 14

The mass of living material
Energy stored in biomass is transferred along food chains and used by other organisms to build biomass

Question 15

What are 3 environmental changes?

Answer 15

1: water availability (how much rainfall)
2: temperature
3: atmospheric gases (how much air pollution)

Question 16

Tell me about recycling materials.

Answer 16

Materials are cycled through the abiotic and biotic parts of an ecosystem
Materials are put into organisms by photosynthesis and absorption from soil
Materials are put into the environment by waste, death and decay

Question 17

What is the water cycle?

Answer 17

Precipitation falls, and evaporation, transpiration and condensation cause it to rise again, and thus the cycle continues

Question 18

What is the carbon cycle?

Answer 18

CO2 in the air gets photosynthesised into carbon compounds in plants. That then gets turned into carbon compounds in animals by eating (which respire which also releases carbon). Those animals then get turned into plant and animal products, which are burned and released into the atmosphere again. The plants/animals also die and decay which creates carbon compounds in the soil that are decayed by microorganisms.
Also there are fossil fuels which get burned as well.

Question 19

What are 3 factors that increase the rate of decay?

Answer 19

1: warm temperature
2: plenty of oxygen
3: moist conditions
Farmers and gardeners make the ideal place for decay and call it compost.

Question 20

What is biogas?

Answer 20

Biogas is produced by anaerobic decay (digestion according to father). It’s mainly made up of methane, which can be burned as a gas.
Biogas is made on a large scale from waste material (eg, sludge from sewage works; or chicken poo) in biogas generators.

Question 21

What is biodiversity?

Answer 21

The variety of different species on Earth, or within an ecosystem

Question 22

What is the order of biodiversity things?

Answer 22

High diversity (lots of different species) > reduced dependence of one species on another for things like food, shelter and maintenance of the physical environment > stable ecosystems

Question 23

What are 3 consequences of global warming?

Answer 23

1: rising sea levels / desertification
2: change in distribution of some organisms
3: decrease of biodiversity

Question 24

What is deforestation?

Answer 24

The cutting down of forests

Question 25

What are 2 reasons deforestation has occurred?

Answer 25

1: clearing land for rice fields and farming cattle
2: growing crops to make biofuels

Question 26

What are 3 ways we pollute the environment?

Answer 26

1: sewage, fertilisers and toxic chemicals from farming and industry get washed into water
2: smoke and acidic gases released into the atmosphere pollute air
3: toxic chemicals and waste dumped in landfill sites pollute land

Question 27

Name 5 programmes to protect ecosystems.

Answer 27

1: breeding programmes - endangered species are bred in captivity to make sure the species survive
2: habitat restoration - rare habitats like mangroves, heathland and coral reefs are protected and regenerated
3: these are reintroduced around fields where only a single crop type is grown, creating habitats for more organisms
4: government regulations - eg, to reduce deforestation and CO2 emissions
5: recycling - reduces the amount of waste going to landfill sites

Question 28

What is a tropic level?

Answer 28

A stage in a food chain

Question 29

What is a pyramid of biomass?

Answer 29

A diagram showing the relative amounts of biomass at each trophic level

Question 30

What are carnivores with no predators called?

Answer 30

Apex predators

Question 31

What are decomposers?

Answer 31

(Bacteria) secrete enzymes to break down dead plant and animal matter into small soluble food molecules, These then diffuse into the microorganisms.

Question 32

What are the 3 reasons biomass is lost between trophic levels?

Answer 32

1: not all of the material ingested by an organism
2: some biomass is lost as waste substances rather being used to build new biomass
3: lots of glucose is used for respiration rather than used to build new biomass

Question 33

What is the equation of biomass transfer (%)?

Answer 33

Biomass transferred to the next level / biomass available at the previous level x100

Question 34

What is food security?

Answer 34

Having enough food to feed a population

Question 35

What is a threat to food security?

Answer 35

1: increasing birth rate
2: changing diets in developed countries (meaning they take scarce food resources from other countries)
3: new pests and pathogens that affect crops and livestock
4: environmental changes that affect farming (eg, changes in rainfall patterns)
5: cost of farming
6: conflict

Question 36

How can food be produced more efficiently?

Answer 36

By reducing the energy transferred from livestock to the environment, for example:
By restricting movement
By keeping animals in temperature-controlled environments

Question 37

What is overfishing?

Answer 37

Fish stocks are declining due to overfishing. We need to maintain stocks at a level where the fish continue to breed. This can be done by:
1: introducing fishing quotas
2: controlling net size

Question 38

What is biotechnology?

Answer 38

Where living things and biological processes are used and manipulated to produce a useful product. It can be used to produce food for the growing human population.
Genetically modified crops can produce more food or food with greater nutritional value - eg, ‘golden rice’ produces a chemical that’s converted into vitamin A in the body.