Population Size & Ecosystems

Question 1

Population

Answer 1

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

Question 2

Habitat

Answer 2

The physical environment where a particular population is found

Question 3

Ecosystem

Answer 3

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

Question 4

Birth rate

Answer 4

Reproductive capacity of a population, number of new individuals derived from reproduction per unit time

Question 5

Immigration

Answer 5

The 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 be reproduction and dispersal

Question 7

Environmental resistance

Answer 7

Environmental factors that slow down population growth

Question 8

Environment

Answer 8

Set of external conditions that surround an organism

Question 9

Biotic

Answer 9

A part of the environment of an organism that is living

Question 10

Abiotic

Answer 10

A part of the environment of an organism that is non living e.g. Air Temperatures oxygen availability

Question 11

Carrying capacity

Answer 11

The max number around which a population fluctuated in a given environment

Question 12

Niche

Answer 12

The place where an organism is found and it’s role in an ecosystem

Question 13

Exponential

Answer 13

When the number of individuals in the population doubles per unit time

Question 14

Abundance

Answer 14

The number of individuals in a species in a given area

Question 15

Biomass

Answer 15

The mass of biological material in living organism

Question 16

Tropic level

Answer 16

The number of times that energy has been transferred between the sun and successive organisms along a food chain

Question 17

Saprobiont

Answer 17

A micro organism that obtains its food from the dead or decaying remains of other organisms

Question 18

Gross primary productivity

Answer 18

The rate of production of chemical energy in organic molecules by photosynthesis in a given area at a given time

Question 19

Net primary productivity

Answer 19

Energy in the plants biomass which is available to primary consumers

Question 20

What is GPP & NPP measured in

Answer 20

Kjm-2y-1

Question 21

Primary productivity

Answer 21

The rate at which energy is converted by producers into biomass

Question 22

Secondary productivity

Answer 22

The rate at which consumers convert the chemical energy of their food into biomass

Question 23

Succession

Answer 23

The change in structure and species composition of a community over time

Question 24

Climax community

Answer 24

A stable community that has reached equilibrium with its environment where no further change occurs

Question 25

Primary succession

Answer 25

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

Question 26

Pioneer species

Answer 26

The first species to colonise a new area in an ecological succession

Question 27

Serial stage

Answer 27

The different stages in succession where particular communities dominate

Question 28

Secondary succession

Answer 28

The changes in a community following the disturbance or damage to a colonised habitat

Question 29

Mutualism

Answer 29

An interaction between organisms of two species from which both derive benefit

Question 30

Commensalism

Answer 30

An interaction between organisms of two species from which one benefits but the other is not affected

Question 31

Global Warming

Answer 31

The increase of average global temperature in excess of the greenhouse effect caused by the atmospheres historical concentration of carbon dioxide

Question 32

Carbon Footprint

Answer 32

The equivalent amount of carbon dioxide generated by an individual, product or a service in a year

Question 33

Nitrogen Fixation

Answer 33

The reduction of nitrogen atoms in nitrogen molecules to ammonium ions by prokaryotic organisms

Question 34

Eutrophication

Answer 34

The artificial enrichment of aquatic habitats by excess nutrients often caused by run off fertilisers

Question 35

What is interspecific competition

Answer 35

Competition between individuals of different species

Question 36

What is intraspecific competition

Answer 36

Competition between individuals of the same species

Question 37

What human activities lead to an increase in carbon dioxide in the atmosphere

Answer 37

Burning of fossil fuels and deforestation

Question 38

What is putrefaction (ammonification)

Answer 38

Occurs when saprophytic bacteria metabolise the nitrogen containing organic matter in dead organisms faeces and urine and release ammonium ions

Question 39

Latin word for nitrites

Answer 39

Nitrosomonas

Question 40

Latin word for nitrites

Answer 40

Nitrobacter

Question 41

What is nitrification

Answer 41

Under aerobic condition nitrifying bacteria converts ammonia to nitrites and nitrites to nitrates

Question 42

What is denitrification

Answer 42

Denitrifying bacteria convert nitrates and ammonium ions into atmospheric nitrogen - ANAerobic conidiotns Removes nitrogen from ecosystems

Question 43

What is nitrogen fixation

Answer 43

Convert atmospheric nitrogen into ammonium ions, brought about by rhizobium and azotobacter

Question 44

What are the stages of the nitrogen cycle

Answer 44

Putrefaction Nitrification Detrification Nitrogen fixation

Question 45

Tropic level

Answer 45

Is the position in a food chain