Section 8 - Ecology & the enviroment Flashcards
1
Q
Def of habitat
A
place where organisms live
2
Q
Def of population
A
All the organisms of one species in a habitat
3
Q
Def of community
A
All different species in a habitat
4
Q
Def of ecosystem
A
All the organisms living in a particular area and all the non-living conditions
5
Q
What causes changes in the enviroment?
A
- abiotic factors (non-living)
- biotic factors (living)
6
Q
Examples of abiotic factors:
A
- Enviromental conditions - temperature, light intensity, soil pH
- Toxic chemicals - pesticides + fertilisers
7
Q
Examples of biotic factors:
A
- Availability of food
- number of predators
- Competition with other organisms
8
Q
Order of food chains:
A
- Producer - plant
- primary consumer
- secontay consumer
- tertiary consumer
- decomposers - bacteria
9
Q
pyramids of numbers
A
number of each type of organims in a habitat
10
Q
pyramids of biomass
A
the weight of all the organisms of each level together
11
Q
pyramids of energy transfer
A
always pyramid-shaped
12
Q
Energy transfer along food chain steps:
A
- Sun
- Plants
- Some parts of foods arent eaten by organisms so energy is lost - 90%
- Most energy transferred to surounding by heat
- 10% becomes biomass - energy that is trasferred form a trophic level to another
13
Q
Carbon cycle
A
there is only a fixed amount of carbon on the enviroment so is recycled
14
Q
steps of the carbon cycle
A
- whole thing powered by plants and by photosynthesis they transfom co2 into carbohydrates . .
- carbon compunds pass to animals by eating
- respiration releases co2 back into air
- plants and animals when they die are decomposed by bacteria and fungi
- decomposers release co2 into the air
- combustion of wood and fossil fuels also releases co2
15
Q
Carbon monoxide
A
- its poisonous
- created when fossil fuels are burnt without enough air supply
- combined with haemoglobin in red blood cells can prevent them form carrying oxygen
