VANDERS HUMAN PHYSIOLOGY MECHANISM
OF BODY FUNCTION COMPREHENSIVE STUDY
GUIDE 2026 BODY SYSTEM FUNCTION AND
REGULATION PRINCIPLES
◉ peripheral nervous system (PNS). Answer: the nerves that
connect the brain and spinal cord with the body's muscles, glands,
sense organs, and other tissues
◉ neuron. Answer: The functional unit of the nervous system is the
individual cell. They generate electrical signals that move from one
part of the cell to another part of the same cell or to neighboring
cells
◉ neurotransmitters. Answer: chemical messengers that are
triggered by the electrical signals that neurons send out. They
communicate with other cells.
◉ cell body (soma). Answer: contains the nucleus and ribosomes
and thus has the genetic information and machinery necessary for
protein synthesis
,◉ dendrites. Answer: a series of highly branched outgrowths of the
cell that receive incoming information from other neurons. These
increase the cell's surface area
◉ dendritic spines. Answer: knoblike outgrowths that increase the
surface area of dendrites still further and receive signals from axons
at the synapse
◉ the structure of dendrites in the CNS. Answer: increases a cell's
capacity to receive signals from many other neurons
◉ axon. Answer: a long process that extends from the cell body and
carries outgoing signals to its target cells. They range in length from
a few microns to over a meter
◉ axon hillock (initial segment). Answer: The region of the axon that
arises from the cell body and where propagated electrical signals are
generated
◉ collaterals. Answer: branches of the axon
◉ The greater the degree of branching of the axon and axon
collaterals. Answer: the greater the cell's sphere of influence
, ◉ axon terminal. Answer: endings of collaterals that are responsible
for releasing neurotransmitters from the axon
◉ varicosities. Answer: A series of bulging areas along the axon
where some neurons release their chemical messengers.
◉ myelin sheath. Answer: covers around the axon that consist of 20
to 200 layers of highly modified plasma membrane wrapped around
the axon by a nearby supporting cell. They speed up conduction of
the electrical signals along the axon and conserve energy
◉ oligodendrocyte. Answer: a type of glial cell in the CNS that wraps
axons in a myelin sheath. Each may branch to form myelin on as
many as 40 axons
◉ Schwann cells. Answer: glial cells in the PNS that form individual
myelin sheaths surrounding the axon
◉ nodes of Ranvier. Answer: the spaces between adjacent sections of
myelin where the axon's plasma membrane is exposed to
extracellular fluid
◉ axonal transport. Answer: the movement of various organelles
and other materials between the cell body and the axon terminals to
maintain the structure and function of the axon
OF BODY FUNCTION COMPREHENSIVE STUDY
GUIDE 2026 BODY SYSTEM FUNCTION AND
REGULATION PRINCIPLES
◉ peripheral nervous system (PNS). Answer: the nerves that
connect the brain and spinal cord with the body's muscles, glands,
sense organs, and other tissues
◉ neuron. Answer: The functional unit of the nervous system is the
individual cell. They generate electrical signals that move from one
part of the cell to another part of the same cell or to neighboring
cells
◉ neurotransmitters. Answer: chemical messengers that are
triggered by the electrical signals that neurons send out. They
communicate with other cells.
◉ cell body (soma). Answer: contains the nucleus and ribosomes
and thus has the genetic information and machinery necessary for
protein synthesis
,◉ dendrites. Answer: a series of highly branched outgrowths of the
cell that receive incoming information from other neurons. These
increase the cell's surface area
◉ dendritic spines. Answer: knoblike outgrowths that increase the
surface area of dendrites still further and receive signals from axons
at the synapse
◉ the structure of dendrites in the CNS. Answer: increases a cell's
capacity to receive signals from many other neurons
◉ axon. Answer: a long process that extends from the cell body and
carries outgoing signals to its target cells. They range in length from
a few microns to over a meter
◉ axon hillock (initial segment). Answer: The region of the axon that
arises from the cell body and where propagated electrical signals are
generated
◉ collaterals. Answer: branches of the axon
◉ The greater the degree of branching of the axon and axon
collaterals. Answer: the greater the cell's sphere of influence
, ◉ axon terminal. Answer: endings of collaterals that are responsible
for releasing neurotransmitters from the axon
◉ varicosities. Answer: A series of bulging areas along the axon
where some neurons release their chemical messengers.
◉ myelin sheath. Answer: covers around the axon that consist of 20
to 200 layers of highly modified plasma membrane wrapped around
the axon by a nearby supporting cell. They speed up conduction of
the electrical signals along the axon and conserve energy
◉ oligodendrocyte. Answer: a type of glial cell in the CNS that wraps
axons in a myelin sheath. Each may branch to form myelin on as
many as 40 axons
◉ Schwann cells. Answer: glial cells in the PNS that form individual
myelin sheaths surrounding the axon
◉ nodes of Ranvier. Answer: the spaces between adjacent sections of
myelin where the axon's plasma membrane is exposed to
extracellular fluid
◉ axonal transport. Answer: the movement of various organelles
and other materials between the cell body and the axon terminals to
maintain the structure and function of the axon
