Glossary

Question 0

Community

Answer 0

All the organisms living in a habitat.

Question 1

Biodiversity

Answer 1

Refers to the number and abundance of species.

Question 2

Ecosystem

Answer 2

Natural biological unit composed of habitats, populations and communities.

Question 3

Niche

Answer 3

The role an organism has within it’s community in an ecosystem

Question 4

Ammonium

Answer 4

A nitrogen containing waste product of decomposition

Question 5

Competition

Answer 5

Interaction between organisms seeking the same limited resources

Question 6

Denitrifying bacteria

Answer 6

Converts nitrates in the soil into nitrogen gas, which is released into the atmosphere

Question 7

Nitrifying bacteria

Answer 7

Produces nitrate, which is released into soil.

Question 8

Nitrogen fixing bacteria

Answer 8

Bacteria found free living in the soil or in the root nodules of some plants that convert nitrogen gas into nitrate

Question 9

Pyramid of biomass

Answer 9

Diagram that shows the relative total masses of the organisms at each level in a food chain

Question 10

Pyramid of energy

Answer 10

Diagram that shows the relative quantities of energy at each level in a food chain

Question 11

Pyramid of numbers

Answer 11

Diagram that shows the relative quantities of organisms at each level in a food chain

Question 12

Pitfall trap

Answer 12

Sampling technique used to trap animals living on the soil surface or in leaf litter.

Question 13

Quadrat

Answer 13

Square frame of known area used for sampling the abundance and distribution of slow or non moving organisms.

Question 14

Qualitative

Answer 14

Able to be expressed as presence or absence

Question 15

Quantitative

Answer 15

Able to be expressed using numerical values

Question 16

Adaptation

Answer 16

Feature of an organism that helps it to survive

Question 17

Mutation

Answer 17

A random and spontaneous change in the structure of a gene, chromosome or number of chromosomes; only source of new alleles.

Question 18

Selection pressure

Answer 18

Factor such as predation or disease that affects a population, resulting in the death of some individuals and survival of others.

Question 19

Selective advantage

Answer 19

An increased chance of survival for an organism because of possession of favourable characteristics.

Question 20

Speciation

Answer 20

Formation of two or more species from an original ancestral species.

Question 21

Biological control

Answer 21

Natural control of pests using natural predators, parasites etc.

Question 22

Indicator species

Answer 22

Organisms that give information such as level of pollution in the environment.