ANSWERS GUARANTEE A+
✔✔Describe the structure and function of the dendrite - ✔✔numerous short extensions
that emanate from the cell body which receive information from other neurons
conducting nerve impulses toward the cell body
✔✔Describe the axon, including the number in each neuron, function, structure and
organelles. - ✔✔conducts nerve impulses away from the cell body to its axon terminals
where it is emitted across a synapse to the dendrite of another neuron. Axons are
composed of cells like the cell body but lack rough ER.
✔✔Describe the function and site of synthesis and storage of neurotransmitters. -
✔✔chemicals stored in secretory vesicles at the end of axon terminals. When
neurotransmitters are released by the axon terminal vesicles, they carry the
transmission of the nerve impulse from one neuron to another
✔✔What is a synapse? - ✔✔A gap between neurons
✔✔A post-synaptic neuron is a neuron that is found ____ the synapse - ✔✔After
✔✔_____neurons have three or more extensions from the cell body and have one axon
and many dendrites - ✔✔Multipolar
✔✔_________ neurons have a central cell body with two extensions - ✔✔Bipolar
✔✔_____ neurons have one extension off the cell body which branches into two: one
central process running to the CNS and another peripheral process running to the
sensory receptor - ✔✔Unipolar
✔✔______ neurons are unipolar and function to carry information from the peripheral to
the central nervous system - ✔✔Sensory
✔✔These types of neurons are also called association neurons - ✔✔Interneurons
✔✔_____ neurons send messages from the central nervous system to the peripheral -
✔✔Motor
✔✔What is the function of neuroglial cells? - ✔✔support cells, helping to support
neurons to enable them to thrive in their needed environment
✔✔What are the peripheral nervous system neuroglial cell types? - ✔✔Schwann cells
and satellite cells
, ✔✔True or False: Axons cannot regenerate in the peripheral nervous system. -
✔✔False
✔✔True or False: Myelin sheath is continuous and has no gaps. - ✔✔False
✔✔List the four types of support neuroglial cells in the central system and a function of
each. - ✔✔Ependymal cells: circulate cerebrospinal fluid and allow fluid exchange
between brain, spinal cord, and CSF
Oligodendrocytes: act as insulation for CNS axons
Astrocytes: control chemical environment of neurons by wrapping around the blood
capillaries, forming blood brain barrier
Microglial cells: protect the CNS by scavenging dead cells and infectious
microorganisms
✔✔What is the technical term used to describe a nerve impulse and what causes the
impulse? - ✔✔action potential and is caused by the movement of unequally distributed
ions on either side of an axon's plasma membrane
✔✔An axon's membrane is polarized with a resting potential of -70 mV. Explain what
this means and what maintains this resting potential. - ✔✔the plasma membrane is
polarized. this difference is called a resting potential means that the charge on the
inside of the axon's cell membrane is 70 mv less than the outside. The sodium
potassium pump uses active transport to maintain this resting potential.
✔✔What are the four steps of an action potential in order? - ✔✔resting potential,
depolarization, repolarization, after polarization
✔✔Describe what happens to the charges on the axon cell membrane during
depolarization and what causes this to happen. - ✔✔sodium gates open and sodium
rushes into the axon and the inside becomes more positive than the outside causing the
membrane potential to become more positive
✔✔Describe what happens to the charges on the axon cell membrane during
repolarization and what causes this to happen. - ✔✔sodium gates close and potassium
gates open allowing potassium to rush out of the axon. this returns a negative charge to
the inside of the axon re-establishing the negative potential
✔✔Describe what happens during afterpolarization - ✔✔the potassium gates that open
during repolarization are slow to close and there is an afterpolarization undershoot of
the potential
✔✔What causes the difference in intensity of a sensation? - ✔✔due to the number of
neurons stimulated and the frequency with which they are stimulated