The Nervous System B3 Flashcards
What are the names of the 2 nervous systems and what do they contain?
The central nervous system which is made from the spinal cord and brain. The peripheral nervous system which is made of all the other nerve cells that connect to the central nervous system.
How does the central nervous system coordinate a response?
The nervous system is made up of neurones which go to all parts of the body. The body had lots of sensory receptors which can detect a stimulus. Different sensory receptors detect different stimuli (e.g. receptors in eyes detect light). Once a stimulus is detected the information is sent as an electrical impulse along sensory neurones to the CNS. The CNS then sends information to an effector (muscle or gland) along a motor neurone. The effector then responds accordingly (e.g. muscle may contract)
What does a myelin sheath do?
Myelin sheath speeds up the electrical impulse.
What is a synapse?
A synapse is a tiny gap between two neurones.
Describe the process of a reflex arc.
The receptor detects a stimuli and sends a message along the sensory neurone, the message is then passed onto the relay neurone, then the message gets to the CNS and impulse crosses synapse to relay neurone and then back along a motor neurone, finally the message reaches the muscle and it contracts.
Which direction does a sensory neurone move?
A sensory neurone impulses move towards the cell body.
Which direction does a relay neurone travel?
The relay neurone impulses travel first towards the cell body and then away from the cell body.
Which direction do motor neurones travel?
Motor neurone impulses travel away from the cell body.
What sense organ detects which stimulus?
Eye receptors detects light, ear receptors detect sound, nose receptors detect smell, tongue receptors detect taste and skin receptors detect touch, pressure, pain and temperature change.
What is a reflex
A reflex is an automatic response to certain stimuli and you do not think about them.
