AQA Biology B1a - Human Biology

B1a - Human Biology

The Nervous system:

Stimulus - change in your environment

Receptors - a group of cells which are sensitive to a stimulus

Sensory Neurones - The nerve cells that carry signals from the receptors to the CNS

Motor Neurones - The nerve cells that carry signals to the effector muscles or glands

Effectors - Muscles and glands that respond to impulses from the motor neurones

Central nervous System (CNS) - The brain and spinal cord where reflexes and actions are coordinated

Synapse - The connection between two neurones

SENSORY ORGANS + RECEPTORS ARE TWO DIFFERENT THINGS! 

Sensory organs e.g eyes contain receptors (eyes contain light receptors)

Sensory organ: Receptor:

Eyes Light

Ears Sound

Nose Smell

Tongue Taste

Skin Touch, Pressure, Temperature change

Reflexes:

Reflexes are automatic responses to certain stimuli - they can reduce the chances of being injured. For example, when a light…