19 - Populations in Ecosystems

Question 1

ecosystem

Answer 1

consists of a community and the non-living components of its environment

Question 2

abiotic factors

Answer 2

non-living

eg. weather

Question 3

biotic factors

Answer 3

living factors

eg. predation, competition, disease

Question 4

population

Answer 4

group of individuals of one species that occupy the same habitat at the same time

Question 5

community

Answer 5

group of individuals formed by populations of different species

Question 6

carrying capacity

Answer 6

size of a population of a species which an ecosystem can support

Question 7

niche

Answer 7

an organism’s habitat, what it does there, and the adaptations it has to the biotic and abiotic conditions of its habitat
unique to each organism

Question 8

methods to estimate size of population

Answer 8

randomly placed quadrats (or along a belt transect) for slow moving/immobile organisms
mark-release-recapture method for motile organisms

Question 9

ecosystems are dynamics systems, meaning

Answer 9

they are constantly changing

Question 10

succession

Answer 10

used to describe the process by which an ecosystem changes over time

Question 11

stages of succession

Answer 11

1. pioneer species colonise an inhospitable area
2. pioneer species alter the abiotic environment and it is more suitable for other species
3. these other species also change the abiotic environment by providing ore sources of food
4. this enables a more complex food web to establish
5. this process continues and eventually reaches a balanced equilibrium of species and high biodiversity
6. the result is called a climax community