humans and envrioment

Question 1

humans cause pollution in

Answer 1

water -eutrophication
air - greenhouse gases
land - landfills

Question 2

humans reduce amount of land for plants and animals through

Answer 2

building
farmin
dumping waste
quarrying

Question 3

greenhouse effect

Answer 3

trapped heart as co2 and methane create a barrier so it can’t get out

Question 4

how is co2 levels increasing

Answer 4

deforestation - less photosynthesis

destruction of peat bogs - carbon isn’t stored and is released in the destroyal

Question 5

effects of climate change

Answer 5

sea level rise due to water expanding when heated and ice caps melting
extreme weather like hurricanes
distribution of species change
changes in migration of animals

Question 6

what are biofuels

Answer 6

alternative to fossil fuels to produce energy made my fermentation (breaking down using yeast or bacteria) of waste products
eg, ethanol made by fermentation of sugar, broken down by yeast, distilled from yeast to make ethanol

Question 7

what is biogas

Answer 7

another alternative to fossil fuels
anaerobic fermentation of waste, 70% methane and 30% co2
happens in generator or digester at a constant temp so microorganisms don’t respire away

Question 8

biogas generators

Answer 8

batch generators 
small scale
manually loaded
continuos generators 
large scale
continuously creates biogas

Question 9

things to consider when designing a biogas generator

Answer 9

cost, batch cost less
converniance, continuous means constant supply
efficiency, both need to be 33 degrees
location, the waste smells, can’t be hear houses

Question 10

positives of biofuels and biogases

Answer 10

carbon neutral
no greenhouse gasss that cause acid rain
treats waste that affects atmosphere like methane
waste is cheap and readily available
gets rid of waste