B7 Ecology v2 Flashcards
two reasons why high biodiversity is important
“keeps ecosystems stable bcz different species rely on each other for food. different species also
maintain the correct physical environment for each other.”
two reasons why the earths population is rising so quickly
modern medicine and modern farming
two reasons why a larger population is putting huge demands on the environment
- survival
- higher standard of living
what are three types of waste we produce with example of each
air (smoke and acidic gases), water (sewage polluting lakes), land (toxic chemicals used for farming).
what are the two main greenhouse gases
carbon dioxide and methane
give three consequences of climate change
ice caps melting, distribution of animals due to rainfall pattern changes, reduction in biodiversity
four things humans use land for
building, quarrying, farming and waste dumping.
3 consequences of chopping down trees
less carbon dioxide taken in, more carbon dioxide in the atmosphere, less biodiversity
what are peat bogs, what happens to them and why
area of land that are acidic and waterlogged, plants don’t decay in them due to lack of oxygen
why is destroying peat bogs bad for the atmosphere
carbon in plants is stored in the peat, so it would therefore release co2 into the atmosphere
list four programs created to protect biodiversity
breeding, rare habitat protection, hedgerows, deforestation reduction
list three conflicting pressures when it comes to biodiversity
Cost, destruction of livelihoods, high demand for land
what are trophic levels
different stages of the food chain which contain organism(s) that perform a specific role in the food chain
what does trophic level 1 contain
producers such as plants and algae which make their own food from the sun
what does trophic level 2 contain
tertiary consumers such as wolfs which have no predators above them
give two examples of decomposers and why they are important
bacteria and fungi, they continue the carbon cycle
what three things are there less of as you move down the trophic levels
biomass, energy, organisms
what does a pyramid of biomass show
It visually displays the amount of organisms in each trophic of the food chain and how much of one species is feeding on another
how do decomposers break down material in an environment
by secreting enzymes
how does biomass pass through a food chain
when organisms eat other organisms
what is biomass
the total quantity or weight of organisms in a given area or volume
what percentage of biomass is actually usually passed on between each trophic level
10%
three reasons why only a small percentage of biomass is passed between trophics
- energy secreted by feces
- not all of the organism is actually consumed
- energy is used for other things such as keeping warm
What is the equation for biomass efficiency
(biomass at next level/biomass at previous level) x 100
what is the definition of food security
having enough food to feed the whole population
list three things that threaten food security
soaring population, pathogens on farms, conflict
how can food production be made more efficient
through limiting the movement of livestock and keeping them in a temperature controlled environment
two specific way food production can be made more efficient
feeding calves chickens and fish high protein food to further increase growth. factory farm them in cages
What is biotechnology
where living things and biological processes are manipulated to produce a useful product
what is mycoprotein
food made from fungi, such as quorn
how can bacteria be engineered to produce human insulin
“plasmid is removed from bacterium, insulin gene is cut out of human chromosome using a restriction enzyme, which is also used to cut
open the plasmid. the plasmid and insulin gene are mixed, ligase is then added to end up with millions of bacteria that produce insulin”
