5-hydroxytryptamine (serotonin). Biologically active amine occurring as a hormone in plants and as both a hormone and a neurotransmitter in animals. Like acetylcholine, adrenalin and noradrenalin, serotonin acts on many organs of the body, either directly or by a neuronal reflex.

Period after a meal during which glucose is entering the bloodstream after its absorption from the gut.

A neurotransmitter. (Adj. cholinergic.)

A pulse of electricity that is generated in neurons and travels their length. The means of communication within neurons. Action potentials are ‘all-or-none’, meaning that they either occur in full or not at all.

The region of an enzyme molecule where the substrate binds and catalysis occurs.

Transport processes across membranes that require the expenditure of energy and use specialised transport molecules.

Variations in body structure, or function, or behaviour, which give some members of a species a survival advantage and hence increase their chances of leaving more surviving offspring than other members of the same species.

See

Tissue composed of fat cells (adipocytes). The site of storage of fats (triacylglycerols).

Term used in psychology and psychiatry as a way of describing a person’s responses of emotion and attention to events in the world around them.