4. Ecology And The Evironment

Question 1

Pollution

Answer 1

Releasing harmful substances into the environment in amounts that cause harmful effects and which biological processes cannot easily remove

Question 2

Greenhouse gases

Answer 2

• methane (generated by bacteria in anaerobic/low oxygen conditions e.g. cattle)
• water vapour
• nitrous oxide (burning fossil fuels)
• carbon dioxide (burning fossil fuels)
• CFCs (used as a solvent for aerosols like deodorant)

Question 3

Sulphur dioxide

Answer 3

• formed when fossil fuels are burnt since they contain sulphur
• sulphur dioxide reacts with oxygen in the air and dissolves in rain water to produce sulphuric acid
• creates acid rain
  + nitric acid

Question 4

What does acid rain cause

Answer 4

• death of confir trees -> loss of habitat, loss of species diversion, more CO2 less photosynthesis
• damage of leaves/flowers
• acidification of soil -> leaching of ions onto lakes kills fish or acidifies them directly, killing fish which results in change of ecosystem

Question 5

Carbon monoxide in humans

Answer 5

CO binds irreversibly to haemogoblin
-> less oxygen transported to repairing cells
-> less energy released
-> loose consciousness/death from lack of CO2

Question 6

Deforestation

Answer 6

Clearing of trees, usually on a large scale
-> done for land farming, palm oil production, new homes
-> removal of habitat decreases biodiversity

Question 7

Greenhouse gas effect

Answer 7

Sun emits radiation -> some is reflected by earths atmosphere but some pass through and is absorbed by earths surface

Question 8

Effects of global warming

Answer 8

• melting of polar ice caps -> leads to sea level rising, causing flooding in some regions
• destruction of habitats -> leads to extinction of species
• increased extreme weather events -> more energy present due to global warming
• increase in heat related illness/death