B4 key words

habitat

habitat

a place where plants animals and microoragnisms live

abitotic

non living elements of an ecosystem e.g. climate, temp, water and soil type

community

all the organisms that live in an area

ecosystem

the living organisms in a particular area, together with the non-living components of the environment

biotic

living elements of an ecosystem e.g. plants and animals

predation

the act of a predator feeding on its prey

predator

organism that hunts

prey

organism that is attacked/killed

interdependence

all organisms that live in an ecosystem depend on each other for food, protection, shelter etc. in order to survive

trophic levels

describe feeding positions in food chains. Energy is transferred from one trophic level to the next along the food chain.

parasitism

where one organism benefits but the other is harmed by the relationship e.g.tape worms

mutualism

where both organisms benefit from the relationship (different species) e.g. cleaner fish eat dead skin off larger fish

pyramid of number

the area of each bar represents the number of organisms at each trophic level

pyramid of biomass

the area of each bar represents the amount of organic matter at each trophic level

efficiency of energy transfer = ?

energy transferred to next level(output)/energy in previous level(input) x100

efficiency of biomass = ?

biomass available before transfer/biomass available after transfer x100

decomposers

organisms that gain their energy by feeding on dead or decaying material

detritivore

small animal that breaks down organic matter into small pieces

sppeds up decomposition

rate of decay (g/day) = ?

change in mass/time

denitrifying bacteria

in the soil breaking down nitrates, releasing nitrogen into the air

nitrogen fixing bacteria

convert nitrogen gas into a useable form for the plants - plants can take up ions by active transport

nitrifying bacteria

converting ammonia (in urine) into nitrates