The human nervous system key terms

cerebellum

The region of the brain responsible for coordinating muscular activity and maintaining balance.

muscular coordination

The ability of the brain and muscles to work together to produce smooth and controlled movements.

medulla

The medulla is the part of the brain that controls unconscious activities such as breathing and heart rate.

unconscious activities

Unconscious activities are functions of the body that occur without conscious thought, including processes like breathing and regulating heart rate.

brain complexity

The intricate structure and function of the brain, which consists of billions of interconnected neurones, making it challenging to study and treat disorders.

delicate nature

The sensitivity of brain tissue, which requires careful handling during investigations and treatments to avoid damage.

brain damage

Injury to the brain that can affect cognitive, physical, and emotional functions, often studied to understand brain function.

neuropsychological assessment

A comprehensive evaluation of cognitive, motor, behavioral, and emotional functions to assess the impact of brain damage.

electrical stimulation

A technique used to study brain function by applying electrical currents to specific brain regions to observe effects on behavior and neural activity.

MRI scanning

A non-invasive imaging technique that uses magnetic fields and radio waves to create detailed images of the brain, allowing for the study of brain structure and function.

brain procedures

Medical interventions performed on the brain to treat disorders or injuries, which can have both benefits and risks.

nervous system risks

Potential negative outcomes associated with procedures on the nervous system, including complications or side effects.

retina

The light-sensitive layer at the back of the eye that contains receptor cells sensitive to light intensity and color.

optic nerve

In The eye (biology only), optic nerve means the structure that carries visual impulses from the retina to the brain. This matters in The human nervous system because it supports the learning objective to identify the retina, optic nerve, sclera, cornea, iris, ciliary muscles, suspensory ligaments and lens in the eye. Use optic nerve only in this subtopic-relevant sense so the definition stays concise, curriculum-specific, and useful for AQA GCSE Biology revision. Students should use this term accurately when they explain the biology, identify symptoms, or justify an answer in GCSE Biology questions.

retina

The light-sensitive layer at the back of the eye that contains receptor cells sensitive to light intensity and color.

receptor cells

Specialized cells in the retina that detect light and convert it into electrical signals for the brain.

optic nerve

In The eye (biology only), optic nerve means the structure that carries visual impulses from the retina of the eye to the brain. This matters in The human nervous system because it supports the learning objective to describe the optic nerve as the structure that carries impulses from the eye to the brain. Use optic nerve only in this subtopic-relevant sense so the definition stays concise, curriculum-specific, and useful for AQA GCSE Biology revision. Students should use this term accurately when they explain the biology, identify symptoms, or justify an answer in GCSE Biology questions.

impulses

Electrical signals transmitted by neurones that convey information from sensory receptors to the brain.

sclera

In The eye (biology only), sclera means the tough supporting outer layer of the eye that provides structure and protection. This matters in The human nervous system because it supports the learning objective to describe the sclera as the tough supporting outer layer of the eye. Use sclera only in this subtopic-relevant sense so the definition stays concise, curriculum-specific, and useful for AQA GCSE Biology revision. Students should use this term accurately when they explain the biology, identify symptoms, or justify an answer in GCSE Biology questions.

eye

The organ that detects light and enables vision, consisting of various structures including the sclera.

cornea

In The eye (biology only), cornea means the transparent outer region of the eye that refracts light entering the eye. This matters in The human nervous system because it supports the learning objective to describe the cornea as a transparent outer region that refracts light entering the eye. Use cornea only in this subtopic-relevant sense so the definition stays concise, curriculum-specific, and useful for AQA GCSE Biology revision. Students should use this term accurately when they explain the biology, identify symptoms, or justify an answer in GCSE Biology questions.

refraction

The bending of light as it passes through the cornea and lens, allowing the eye to focus on objects.

iris

In The eye (biology only), iris means the coloured part of the eye that controls the diameter of the pupil. This matters in The human nervous system because it supports the learning objective to describe the iris as the coloured part of the eye that controls the diameter of the pupil. Use iris only in this subtopic-relevant sense so the definition stays concise, curriculum-specific, and useful for AQA GCSE Biology revision. Students should use this term accurately when they explain the biology, identify symptoms, or justify an answer in GCSE Biology questions.

pupil

The pupil is the adjustable opening in the iris that lets light enter the eye. In the eye subtopic, pupil diameter changes because the iris controls how much light reaches the retina.

ciliary muscles

Muscles that control the shape of the lens during accommodation by contracting or relaxing.

suspensory ligaments

Fibrous strands that connect the ciliary muscles to the lens, helping to change its shape for focusing.

accommodation

The process by which the eye adjusts the shape of the lens to focus on near or distant objects.

ciliary muscles

Muscles that control the shape of the lens in the eye, enabling accommodation for focusing on objects at varying distances.

accommodation

The process by which the eye adjusts the shape of the lens to focus on objects at different distances.

ciliary muscles

Muscles that control the shape of the lens in the eye, allowing for focusing on near and distant objects.