Topic 2B Nervous control Flashcards
What is the nervous system?
The system that allows you to react to your surroundings.
For you to survive organisms need to…
React to stimuli
What are sensory receptors?
Groups of cells that detect stimuli and initiate responses to the. Different receptors react to different stimuli.
What’s the central nervous system?
Where all the information from sensory receptors is sent and where the reflexes and actions are coordinated.
What does the CNS consist of?
Brain and spinal cord.
How do neurons transmit information?
Electrical impulses as the CNS is connected to the body by sensory neurones and motor neurones in mammals.
What are effectors?
Muscles or glands which respond to nervous impulses and bring about a response to a stimulus.
What are the different types of neurones?
Sensory neurones
Relay neurones
Motor neurones
What is a sensory neurone?
They carry information as electrical impulses from sensory receptors to the CNS.
What is a relay neurone?
Carry electrical impulses from sensory neurones to motor neurones. Found in the CNS.
What is a motor neurone?
Carry electrical impulses from CNS to the effectors.
What is in the neurone structure
Dendrites, dendrons, an axon and a cell body.
What do dendrons and dendrites do?
Carry nerve impulses towards the cell body.
What do axons do?
Axons carry nerve impulses away from the cell body. Some axons are surrounded by myelin sheath.
What is myelin sheath?
Fatty layer that acts as an electrical insulator to speed up the electrical impulse.
