The brain and eye: Organism level systems: Biology: GCSE (9:1)

Brain

A mass of nerve tissue consisting of billions of interconnected neurones that acts as the main control centre of the nervous system

Cerebral cortex

The outer region of the cerebrum that contains sheets of nerve cells controlling memory, consciousness, language and intelligence

Cerebrum

The main part of the brain that is divided into a right hemisphere and a left hemisphere

Cerebellum

A large structure of the hindbrain that controls fine motor skills including balance and movement

Hypothalamus

A small region at the base of the brain, it directs several maintenance activities such as eating, drinking and controlling body temperature

Pituitary gland

A master gland attached to the hypothalamus, responsible for releasing many different hormones that regulate specific processes and functions

Hindbrain

The lower part of the brainstem that include the cerebellum

Medulla

The base of the brainstem which controls heartbeat and breathing

Eye

A sense organ that detects light and is responsible for vision

Sclera

The white outer part of the eye that provides protection

Cornea

The transparent tissue that covers the front of the eye, it controls and focuses the entry of light into the eye

Iris

The coloured part of the eye behind the cornea that regulates the size of the pupil

Pupil

The dark opening in the centre of the pupil, it varies in size to regulate the amount of light that reaches the retina

Lens

A transparent structure located behind the iris that focuses light on the retina at the back of the eye

Ciliary muscles

Muscles which work with the suspensory ligaments to adjust the shape of the lens in order to focus on near or far objects

Suspensory ligaments

Ligaments which work with ciliary muscles to adjust the shape of the lens in order to focus on near or far objects

Retina

The light-sensitive surface at the back of the eye containing light and colour receptor cells

Optic nerve

The nerve that carries neural impulses from the receptor cells of the eye to the brain

Light receptor cells

Also called rod cells, these are highly light sensitive and are responsible for vision in dimly-lit conditions

Colour receptor cells

Also called cone cells, these can detect a wide spectrum of light and are responsible for the perception of colour