2.86: Describe the Structure and Functioning of a Simple Reflex Arc Illustrated by the Withdrawal of a Finger from a hot Object

REFLEX: Fast and Involuntary Action that Protects the Body from Damage

REFLEX ARC:

WITHDRAWAL OF A FINGER FROM A HOT OBJECT

Diagram showing the Reflex Arc in Response to a Hot Object

PROCESS: Heat (Stimuli) is Detected by the Finger (Receptor) and will Stimulate Sensory Neurons to Carry Electrical Impulses (Messages) to the Central Nervous System (Brain and Spinal Cord) Electrical Impulses will be Passed on to Relay Neurons which will Carry Impulses Through the Central Nervous System where a Response is Decided and is Passed on to the Motor Neurone Motor Neurons will Carry Electrical Impulses to the Biceps (Effector) Biceps (Effector) will Contract and will Withdraw the Finger Away from the Hot Object (Response)