UNIT M Review #1 Q’s
1. A) Neuroglial cells for support and
nourishment and B) Neurons for
transmitting nerve impulses.
2. All nerve cells (neurons) will possess a
Cell body, Dendrites and an Axon.
3. The function of a dendrite is to both
detect neurotransmitter chemicals and
to conduct a nerve impulse toward the
cell body.
4. An axon is defined as a neuron fiber that
carries impulses AWAY from the cell
body.
5. The cell body is the control center of the
cell it posses the nucleus for protein
synthesis and most of the organelles.
6. The white fatty insulated layer that
covers most longer/larger neuron fibers
(axons and dendrites) is known as the
Myelin Sheath.
7. Special Neuroglial cells called SCHWANN
Cells (Neurolemmocytes) are the
supportive cells that form this sheath.
8. The gaps between one Schwann cell and
another are known as NODES Of
RANVIER.
9. The myelin sheath serves two purposes it
protects the fiber and it speeds up
conduction of the impulse.
TYPES OF NEURONS
1. The three different types of neurons are:
A) MOTOR NEURONS (Efferent)
B) SENSORY NEURONS (Afferent)
C) CONNECTOR NEURONS
(Interneurons)
2. The neuron type that sends messages
around the spinal cord and brain are the
INTERNEURONS.
3. MOTOR NEURONS carry impulses out
from CNS out to effectors
(glands/organs/muscles)
4. Sensory Neurons (Afferent) work to carry
impulses from sensory receptors of
sensory organs and tissues toward the
CNS.
5. MOTOR – short Dendrites with long axon
SENSORY – long Dendrite with shorter
axon.
SEE THE PICTURE BELOW.
6. Motor – Cell Body is very central along
cell axis.
Sensory – Cell body is displaced out to
the side.
See picture above
7. MOTOR NEURON = EFFERENT (leaving
or exiting)
8. SESORY NEURON = AFFERENT (arriving
toward)
9. INTERNEURONS are also known as
ASSOCIATION or CONNECTOR neurons.
10. If a motor neuron innervates an effector
it terminates with a special terminal fiber
assembly known as a MOTOR END PLATE.
11. These are called AXON BULBS
Magnified AXON BULB
12. A nerve is like a cable full of microscopic
nerve fibers of the neurons.
- We will go over Review diagrams in class.