The Nervous System Flashcards
The Central Nervous system
consisting of the brain and spinal cord
The peripheral nervous system
consisting of nerves that conduct nerve impulses from the brain to the spinal cord
How do humans respond to stimuli?
- Receptors detect stimuli
- nerve impulses are conducted along a network of nerve cells to the B and SPC
- B and SPC process and integrate the information
- is then conducted along a network of nerve cells from the B and SPC to the effectors(muscles, glands etc.)
Neurons
nervous tissue consisting of millions of nerve cells
FUNCTION OF NEURONS?
conduct nerve impulses from one part of body to another
structural units of the nervous system
Cell body (STRUCTURE OF NEURON)
Consists of:
- cytoplasm
- Nissl granules (rich in RNA involved in protein synthesis)
DENDRITES
Conduct nerve impulses TO the cell body
AXONS
A-away from cell body
conduct nerve impulses AWAY FROM the cell body
Synaptic knobs
Occur at the ends/tips of the axons called terminal branches
MYELIN SHEATH
This encloses the nerve fibers (axons and dendrites) and is formed by specialized cells called SCHWANN CELLS.
FUNCTION OF MYELIN SHEATH
insulates the nerve fibres and accelerates the transmission of nerve impulses
Neurilemma
the outermost layer of the myelin sheath and is essential for repair or regeneration of damaged neurons
Sensory/AFFERENT(same thing) neurons
A-afferent (A-away from receptors)
conducts impulses from the receptors TO the CNS
Motor/EFFERENT neurons
moTOr-to TOWARDS-to receptors
conduct nerve impulses FROM the CNS TO the receptors
Neurotransmitter
a chemical that is released in the synapse to conduct impulses from one neuron to the next (the axon to synaptic knobs)
How nerve impulses travel between neurons?
Each synaptic knob is filled with a neurotransmitter that is released into the synapse. The nerve impulses is conducted via the dendrite towards the cell body of the next neuron.