Keywords - populations in ecosystems

Question 1

ecosystem

Answer 1

All communities, living organisms, biotic/abiotic factors in a particular area; these factors are interacting + interdependent and make up self contained system which is self supporting (energy flow)

Question 2

environment

Answer 2

All the factors in a habitat which affect an organism - may be biotic or abiotic

Question 3

population

Answer 3

All the members of one species in a habitat at one time

Question 4

community

Answer 4

All the organisms in a particular habitat at one time

Question 5

habitat

Answer 5

geographical area occupied by a species (where a species lives)

Question 6

niche

Answer 6

Role of a species within an ecosystem: its location + functions, and its effect on the environment. Two different species don’t normally occupy exactly the same niche in same habitat at same time

Question 7

mark-release-recapture

Answer 7

Method of estimating abundance of motile organisms which involves catching, marking, releasing + recapturing them.
Pop. size calculated as (total in 1st sample * total in 2nd sample) / no. of marked individuals recaptured

Question 8

succession

Answer 8

process by which structure of a biological community evolves over time, specifically refers to the order of colonisation of species in an ecosystem

Question 9

pioneer species

Answer 9

first species to occupy a new habitat + colonise an inhospitable environment; pioneer species change abiotic environment so that it becomes less hostile to other species

Question 10

climax community

Answer 10

end result of succession which is a more or less stable community w/ a variety of plants + animals