Ch18 Biodiversity and ecosystems

Question 1

biodiversity

Answer 1

variety of different species in an ecosystem

Question 2

pollution in water

Answer 2

untreated sewage
toxic chemicals
fertilisers, herbicides + pesticides wash from soil into bodies of water
- encourage microorganism growth
- oxygen levels decrease + aquatic animals die
- bioaccumulation occurs

Question 3

pollution in land

Answer 3

toxic chemicals from industrial waste
sewage
human waste not treated properly
- chemicals + gut parasites
farming
- herbicides + pesticides soak into the soil
- leads to bioaccumulation in food chain

Question 4

pollution in air

Answer 4

smog
- smoke, sulfur dioxide, nitrogen oxide
carbon dioxide emissions
acid rain

Question 5

acid rain formula

Answer 5

sulfur dioxide + nitrogen oxide + oxygen

sulfuric acid + nitric acid

Question 6

consequences of acid rain

Answer 6

neighbouring countries affected
whole ecosystems fail
damages environment

Question 7

human effects on ecosystems

Answer 7

loss of habitat
rising sea levels
change in distribution
decrease in biodiversity
changes in migration patterns
more resources are used
more waste is produced

Question 8

bigger biodiversity means…

Answer 8

more stable ecosystem because it reduces the dependence of species on another

Question 9

land use

Answer 9

building
quarrying
farming
dumping waste

Question 10

peat bogs

Answer 10

carbon sinks
consists of plant material that can’t decay
forms slowly and destroyed quickly
produces garden compost

Question 11

greenhouse effect

Answer 11

Electromagnetic radiation at most wavelengths passes through the Earth’s atmosphere
The Earth absorbs most of the radiation and warms up
The Earth radiates energy as infrared radiation
Some of the infrared radiation goes into space
Some of the infrared radiation is absorbed by greenhouse gases in the atmosphere
The lower atmosphere warms up.

Question 12

Consequences of global warming

Answer 12

increased severe weather events
glaciers melting
sea level rising
patterns of rainfall changing, producing floods or droughts
habitats changing

Question 13

how biomass is lost

Answer 13

egested in faeces
not all food is ingested(hooves, bones, claws and calves)
respiration(glucose and CO2)
water and urea in urine
keeping warm
movement

Question 14

producers

Answer 14

mostly plants and algae

transfer about 1% of the incident energy from light for photosynthesis

Question 15

biomass transfer between trophic levels

Answer 15

approximately 10% of the biomass from each trophic level is transferred

Question 16

Factors affecting food security

Answer 16

1. the increasing birth rate
2. changing diets in developed countries means scarce food resources
   are transported around the world
3. new pests and pathogens that affect farming
4. environmental changes that affect food production, such as widespread famine occurring in some countries if rains fail
5. cost of agricultural inputs
6. conflicts affect the availability of water or food

Question 17

sustainable food security

Answer 17

maintaining soil quality for plants to be grown well year after year
food efficiency
taking care of fish stocks

Question 18

food efficiency

Answer 18

reduce stages in the food chain
restricting energy transfer from animals by limiting movement
controlling environment(temp) animals are kept in
- artificially produces
animals fed high protein foods to increase growth

Question 19

reducing overfishing

Answer 19

imposed quotas

control the size of the nets