biology a-z

Active transport

energy is used to move the particles of a substance against a concentration gradient, that is, from a region where they are of lower concentration to a region where they are of higher concentration

Aerobic respiration

Respiration with oxygen

Alleles

Different forms of a gene which occupy the same relative positions on a pair of homologous chromosomes.

Aneorobic respiration

Respiration without oxygen

Aquaculture

The farming of fish and other seafood

Arteries

Blood vessels which carry blood away from the heart.

Asexual reproduction

The process resulting in the production of genetically identical offspring from one parent, without the fusion of gametes.

Capillaries

Microscopic thin-walled (one cell thick) blood vessels which carry blood from a small artery (arteriole) to a small vein (venule).

Conservation

The protection and preservation of natural resources of the environment.

Consumers

Organisms which obtain their energy by feeding on other organisms.