Topic 5 Ecosystems

Question 1

Population

Answer 1

An interbreeding group of organisms of the same species occupying a particular environment

Question 2

Habitat

Answer 2

The physical environment where a particular population or community is found

Question 3

Ecosystem

Answer 3

A community of living organisms (biotic component) and the abiotic factors that influence them

Question 4

Birth rate

Answer 4

The reproductive capacity of a population and the number of new individuals, derived from reproduction of time

Question 5

Immigration

Answer 5

movement of individuals into a population of the same species

Question 6

Equilibrium species

Answer 6

Species that control their population by competition rather than by reproduction or dispersal

Question 7

Environmental resistance

Answer 7

Refers to environmental factors that slowdown population growth

Question 8

Environment

Answer 8

The set of external conditions biotic and abiotic that surround an organism

Question 9

Biotic

Answer 9

A part of the environment of an organism that is Leavin e.g. pathogens and predators

Question 10

Abiotic

Answer 10

A part of the environment of an organism that is nonliving for example e.g. air temperature and oxygen availability

Question 11

Carrying capacity

Answer 11

The maximum number around which the population fluctuates in a given environmemt

Question 12

Ecological niche

Answer 12

The place where an organism is found and what it does i.e. role in the ecosystem

Question 13

Abundance

Answer 13

The number of individuals in a species in a given area of volume

Question 14

Biomass

Answer 14

Mass of biological material in living or recentl living organisms

Question 15

Gross primary productivity GPP

Answer 15

Rate of production of chemical energy in organic molecules by photosynthesis in a given area in a given time measured in kjm-2y-1

Question 16

Net primary productivity NPP

Answer 16

Energy in a plant biomass which is available to primary consumers

Question 17

Primary productivity

Answer 17

Rate at which energy is converted by producers into biomass

Question 18

Secondary productivity

Answer 18

Rate at which consumers convert the chemical energy of the food into biomass

Question 19

Trophic levels

Answer 19

Position in a food chain

Question 20

Succession

Answer 20

Change in structure and species composition of a community over time

Question 21

Climax community

Answer 21

A stable community that has raised equilibrium with its environment and no further change accuse

Question 22

Primary succession

Answer 22

Change in structure and species composition of a community over time in an area that has not previously been colonised

Question 23

Pioneer species

Answer 23

The first species to colonise a new area in an ecological succession e.g. Algae lichens and mosses in a xerosere

Question 24

Seral stages

Answer 24

The different stages in succession when a particular communities dominate e.g grasses