AQA GCSE Biology - The Nervous System and Homeostasis

Reshapes the cornea surgically- common for myopia.

transparent area in front of sclera; can bend light as it enters.

arterioles dilate, increasing blood flow to surface of skin so more heat is lost through radiation.

layer at back containing light sensitive cells- rods and cones.

Make adjustments to bring body back to bodily norm.

holds lens in place.

reduces heat loss through radiation.

Change in environment body reacts to.

Float on the surface of the cornea, focusing and refracting light.

Carry electrical impulse from Receptor to CNS.

area of cones where light is bought to focus.

sends electrical signal to the brain.

diffuse across the synapse form an area of high concentration to an area of low concentration (down the concentration gradient)

clear disc that can change shape to focus light on retina.

Transmits impulse from CNS to body tissues.

Made up of brain and spinal cord.

controls the size of the pupil.

A(n) ________ is multiple neurons.

hole through which light enters.

tough, white, outer layer- protects eye.

Carry electrical impulse from one part of CNS to another.

All nerves EXCEPT brain and spine.

brings light together before it reaches the eye.

specialized cell

The ________ is comprised of receptors, nerves, the central nervous system (CNS) and effectors.

change the shape of the lens, which alters the refraction of light.

binds to the receptor on the surface of the post- synaptic neuron.

Light hits the ________ and stimulates the rods and cones.

Maintenance of constant internal conditions

Carry electrical impulse from one part of CNS to another

Multiple neurons

Carry electrical impulse from Receptor to CNS

Brain or spine; coordinates response

All nerves EXCEPT brain and spine

Transmits impulse from CNS to body tissues

Change in environment body reacts to

Muscle or gland that reacts to nerve impulse

Specialist cells that detect impulse

Gap between two neurons

transparent area in front of sclera ; can bend light as it enters

holds lens in place

hole through which light enters

area of cones where light is bought to focus

sends electrical signal to the brain

controls the size of the pupil

contracts and relaxes to change the shape of the lens

contract to bring iris further in, opening pupil

contract to dilate pupil by pushing pupil further out

Short-sightedness

spreads light out before it reaches the eye

Long-sightedness

brings light rays together before it reaches the eye

Float on the surface of the cornea, focusing and refracting light

muscles contract and relax rapidly with energy from respiration which is exothermic and releases heat