Ecosystmes TOPIC 7 Flashcards
define ecology
the study of organisms and the environment in which they live in as well as how they both interact
define habitat
a natural home or environment of an animal, pan or other organism
define population
the total number of inhabitants in a particular place
define community
a group of species living in the same place
define ecosystem
the interaction betweeen a community of living and non-living parts of their environment
define interdependance
all the organisms in an ecosystem are dependant on each other to survive
define stable community
the species and environmental factors are in balance so population size remains relatively constant
what are the two types of competition
- intraspecific competition
- interspecific competition
what is itraspecific competition
competition between the same species
what is interspecific competition
competition between different species
what do plants compete for
- light
- space
- mineral ions
- water
what do animals compete for
- food
- water
- territory
- mates
what are abiotic factors
non-living factors (light intensity, temperature)
what are biotic factors
living factors (food availability, new predators)
what cna the change in an abiotic or biotic factor lead to
the increase or decrease in size of the popution in a community
what is a trophic level
a feeding stage within a food chain
what trophic level are producers in
1
what trophic level are tertiary consumers in
4
what is biomass
the total amount of living material in an organism
what do pyramids of biomass show
the amount of living material in each level of a food chain
what happens to the energy at each step along the food chain
it decreases because of heat, bones etc
how much of energy is transferred from one trophic level to the next
10%
wha are the reasons for loss of biomass
- heat
- energy used in repiration
- not all ingested (bones and urine)
what is interdependance shown in
food webs
explain a predator prey relationship
- if the population of prey increases then the population of predators will increase after a lag period
- the increase in predators causes a decrease in prey
- this then causes a decrease in number of prey available so predators decrease
- the decrease means prey will increase
define adaptation
features whihc enable an organism to survive in the conditions in which they live in
what are the different types of adaptation
- structual = body structure
- behavioural = behaviour (hibernation etc)
- functional = internal chnages (urine levels)
what are extremophiles
organisms that live in very extreme conditions (high temp, high pressure, high salt concentration)
