and Physiology I
for Lecture Exam 2.
system includes about 206 bones. These can
be classified according to:
Cranial vs. Postcranial
Axial vs. Appendicular
functions of the skeletal system
Support of the
body, providing shape.
Protection of soft parts.
Movement - redirection of forces generated by the contraction of
Hemopoiesis - production of blood cells.
Mineral sink - storage of calcium and phosphate.
Development of bone.
There are two types of bone based on developmental pattern:
Endochondral bone - preformed
Intramembranous or dermal bone - formed directly in
membranes of dermis.
Bones can be classified on the basis of their shape:
Know an example of each.
Structure of a
typical long bone.
following cell types, their functions and locations where they
Haversian canal (= central canal)
(= haversian system)
canals (= Volkman's canals)
Know the sequence
of events that occurs during the growth of a long
4. Secondary ossification center
Epiphyseal plate (Metaphysis).
processes that occur within the epiphyseal plate (including
the zones of growth),
the classification of bone breaks and the process of healing:
Closed (Simple) fracture
Open (Compound) fracture
Fibrous joints - fibrous (collagenous)
Cartilaginous joints - fibrocartilage.
Synovial joints - synovial membrane and
and examples of each type.
the different types of synovial joints:
Be able to give an example of each.
Posture and support
several different ways a muscle can connect to other parts of
the body: Tendon,
aponeurosis, or direct attachment.
has two points of connection, an origin and an
insertion. The muscle mass
between these points is called the belly.
A muscle is
covered by a thin layer of connective tissue called the
muscle, there are smaller divisions called fascicles, these
are separated by a
fascicle is composed of a large number of individual fibers
(muscle cells) separated
by an endomysium.
fibers are syncitia (multinucleate cells), with
specialized organelles. Know the
actin (thin myofilaments)
myosin fibers (thick
filament theory of muscle contraction. Understand how this
works and what
demonstrates that actin and myosin myofilaments
actually slide together
how the following structures result in myofilament sliding:
Sequence of events:
a nerve impulse
ions to be released from the terminal cisternae of the
Ca++ binds to
troponin, causing a
conformational change in the troponin - tropomyosin
exposes the active site on the actin
The myosin cross
bridge, which has
been activated by the decomposition of ATP into
ADP + P,
immediately binds to the active site on the
The cross bridge
conformational change which results in a sliding of the
actin and myosin myofilaments closer together. This also
causes the ADP and P to be released
from the myosin cross bridge, making it
available for another reaction.
Contraction ceases when nerve impulses stop stimulating the muscle
and Ca++ ions are
pumped into the
sarcoplasmic reticulum, where they remain bound to the protein
until the next nerve impulse arrives.
When Ca++ is no longer available, the
actin and myosin disengage as tropomyosin
resumes its position over the active sites on
mechanics - Know
the following terms:
Know the alternative sources of energy that are available to supply
aerobic respiration –
glycolysis, pyruvate, and the role of the mitochondria
anaerobic respiration –
the roles of glycolysis and lactic acid
Phosphagen system –
the roles of myokinase and creatine phosphate
What is oxygen debt?
What changes result from endurance
training? Power training?
Know differences between Type I (red), Type IIA (intermediate) and Type
IIB (white) fibers.
What are antagonists and synergists? agonists? fixators?
Know the differences between parallel, convergent, pennate (unipennate,
bipennate and multipennate)
and sphincteral muscle types. Know a few
examples of each type.
The Nervous System
Functions: Communication system of body. There
are three types of impulses:
parts of Nervous System:
Cell body (or soma or perikaryon), dendrites, axon.
be bipolar (sensory neurons of retina), multipolar (typical
motor neurons) or
unipolar (typical sensory neurons).
associated w/ nervous system: Neuroglia. 6
Schwann cells – produce myelin sheaths of PNS
Oligodendrogliocytes – produce myelin sheaths of CNS
Microglia – small, phagocytic cells, protective in function
Astrocytes – participate in formation of Blood Brain Barrier
Ependymal cells – aid movement of cerebrospinous fluid within CNS
Satellite (Ganglionic) cells – support neuron cell bodies within
sheaths insulate fibers within and outside of CNS.
These sheaths are separated
from one another by small gaps called the Nodes of
Ranvier, which allow rapid,
the difference between white matter and gray matter.
conduction in nerve cells:
sodium/potassium pump maintains a concentration gradient of Na+ and
K+ ions across
the nerve cell membrane.
in the concentration of positive ions on either side of the
membrane result in an
electrical potential between inside & outside of the
cell (usu. About –70 mV).
is a sudden shift in the balance of ions such that the
difference in electrical
potential decreases between the two sides of the
results in a greater charge differential.
occur in an axon or axon hillock (trigger zone):
electrical potential of the plasma membrane of the soma
adjacent to the axon hillock
rises above -55 mV , then voltage regulated ion gates on
the axon hillock open & allow
a rapid influx of Na+ (depolarization), then a rapid
efflux of K+ (repolarization). Thus,
resting potential is restored.
of ions is then restored by the sodium/potassium pump.
potentials are all-or-none events. Each is
followed by a refractory period during
which balance of ions must be recovered.
potentials are self-propagating within an axon, and are
potentials are also non-decremental.
impulses are transmitted from cell to cell by chemical messengers
neurotransmitters that must be released into the gap
between two cells (called the synapse).
terminals contain vesicles of neurotransmitter that are released
by exocytosis when
an action potential is received.
such as acetylcholine, cross the synapse by
The receiving cell
has special receptor proteins that bind with the
opening of ligand-regulated gates, allowing influx
of Na+ and efflux of K+.
This initiates a
response known as a local potential.
potentials are graded: the more neurotranmitter, the stronger the
potentials may be positive or negative, resulting in
depolarization or hyperpolarization,
potentials are reversible.
Once initiated, the membrane potential will go back to the
resting potential if stimulation stops before an action
potentials are decremental, losing strength as they move away
from the site of the
are rapidly broken down by enzymes of the
postsynaptic cell (e.g.
local potentials are received, they may reach the axon
hillock and stimulate an
potential in the axon.
The Spinal Cord
the basic structure of the spinal
Anterior median fissure
Posterior median sulcus
the various spinal cord tracts
and the regions that they serve.
the structure and function of
spinal nerves and plexuses:
Sympathetic trunk ganglion
how a reflex arc works.
Know the difference between a simple stretch reflex and a
flexor and crossed extensor reflex.
Home | LaDuke
Home | El
Page Design by