The Nervouse System Flashcards
What is the function of the sensory Neuron?
Conduct nerve impulse from sense organs and sensory receptors to the CNS.
What is the function of the interneuron
Conduct impulses with the central nervous system. Internureons relay impulses over short distances from sensory neurone to motor neurone.
What is the function of the motor neurone?
Conduct impulses from the central nervous system to the effector gland, muscle or organ .
The PNS can be subdivide into the somatic (voluntery) why’s is it’s role? Provide examples
The voluntary nerves are under our conscious control for example influencing skeletal muscles
The PNS can be subdivide in autonomic (involuntary)type. What is the role. Provide example
The autonomic system is involuntary and consist of never as involved in arrange of unconscious responses from change in heart rate; h huh land activity .
What is the purpose of meylin sheath?
Allows nerve impulses to travel faster along the neurone that have the sheaths s the impulses jump from one node to node
What is the structure of sensory neurone?
Have long extensions between cell body and deer it’s called dendrons.(extra long receptor)
What should the structure of inter nerves?
They have short axons
What is the structure of motor neurone?
Have short dendrites and long axons
What is a synapse?
A junction between two neurons or between a neuron and an effector at which nerve impulses are transmitted from one to the other.
What is a transmitter?
A chemical that transfers the electrical impulse in one neuron to the next neuron or effector.
What is the direction of a nerve impulse?
From dendrites to axon to axon terminals
What is the role of neurotransmitter nd synaps?
An electrical impulse arrives at the end of a neuron causing sacs containing a chemical called a neurotransmitter to be released into the synapse. The neurotransmitter diffuses across the synapse and binds to the chemical receptors on the next neuron. This causes the electrical impulse to be generated in the next neuron.
What happens to neurotransmitter after its realease
Neurotransmitters in the synaptic cleft must be removed otherwise their continued presence would cause the continual stimulation of the next neuron or the effector which may be a gland thqt secretes a hormone..
Neurotransmitters either
1. Diffuse away quickly
2. Are destroyed by enzymes
3. Are absorbed by the cell that secreted them.
WHAT is a REFLEX RESPONSE?
An involuntary response to a stimulus that is NOT under the direct control of the brain.
• Occurs via a specialised neural pathway called a REFLEX ARC that allows the organism to respond very quickly to the stimulus.
