Simple Reflex Arc Flashcards
All 5 cards in this deck
What is a reflex action?
A rapid, automatic response to a stimulus that does not involve conscious thought.
What is the pathway of a simple reflex arc?
e.g. pulling your hand away from a hot object
- Stimulus detected by a receptor (heat receptor in the skin) → sensory neurone.
- Relay neurone in the CNS (spinal cord).
- Motor neurone → effector (arm muscle contracts and the hand pulls away).
What is the function of a relay neurone?
Connects a sensory neurone to a motor neurone within the CNS.
Why are reflex actions so fast?
The impulse travels a short pathway with few synapses and does not pass through the conscious part of the brain.
True or false? Every reflex arc passes through the conscious part of the brain.
False. Many reflex arcs pass only through the spinal cord, which is why no conscious thought is needed.