BIOS 252 Midterm Review
Definitions:
1. Origin: the attachment of a muscle’s tendon to the stationary bone.
2. Insertion: the attachment of the muscle’s other tendon to the moveable bone
3. Sarcomere: the basic functional units of myofibril. It extends from one Z disc to the next
Z disc.
4. Sarcolemma: the plasma membrane of a muscle cell. Where transverse tubules (t-
tubule) are attached to it and go to the sarcoplasmic reticulum.
5. A band: darker middle part of the sarcomere.
6. I band: a lighter, less dense area that contains the rest of the thin filaments but not thick
filaments, and a Z disc passes through the center of each I band
7. T-Tubules: open to the outside of the fiber, they are filled with interstitial fluid.
8. Elasticity: the ability of muscular tissue to return to its original length and shape after
contraction or extension.
9. Extensibility: the ability of muscular tissue to stretch, within limits, without being
damaged.
10. Contractility: the ability of muscular tissue to contract forcefully when stimulated by an
action potential.
11. Electrical Excitability: ability to respond to certain stimuli by producing electrical signals
called action potentials.
12. Sarcoplasmic Reticulum: a fluid-filled system of membranous sacs encircles each
myofibril.
13. Graded potential: used for short-distance communication only
14. Spatial summation: summation of postsynaptic potentials in response to stimuli that
occur at different locations in the membrane of a postsynaptic cell at the same time.
15. Temporal summation: summation of postsynaptic potentials in response to stimuli that
occur at the same location in the membrane of the postsynaptic cell but at
different times.
16. Agonist: an agent that binds to receptors and enhances or mimics the effect of a natural
neurotransmitter.
17. Antagonist: an agent that binds to and blocks neurotransmitter receptors
18. Synergist: contract and stabilize the intermediate joints, to prevent unwanted
movements at intermediate joints or to otherwise aid the movement of the prime
mover.
,Chapter 10:
1. Comparison of different muscle tissue types (identification, location, voluntary or
involuntary)
Types of Muscular Tissue
o Skeletal muscle: most skeletal muscles move the bones of the skeleton. It is striated
and works mainly in a voluntary manner. Its activity can be consciously controlled by
neurons that are part of the somatic voluntary division of the nervous system.
Function: Move bones
o Cardiac Muscle: forms most of the heart wall. It is also straited, but its action is
involuntary. Alternating contraction and relaxation of the heart is not controlled, rather
the heart beats because it is a natural pacemaker that initiates each contraction.
Autorhythmic: built-in rhythm.
Function: pump blood
o Smooth Muscle: located in the walls of hollow internal structures, such as blood vessels,
airways, and most organs on the abdominopelvic cavity. It is also found in the skin
attached to hair follicles. It is nonstriated and involuntary. Both cardiac and smooth
muscle are regulated by neurons that are part of the autonomic involuntary division of
the nervous system and by hormones released by endocrine gland.
Function: various functions for example peristalsis. Motion (construction of
blood vessels and airways propulsion of foods through gastrointestinal tract,
contraction of urinary bladder and gallbladder).
Fibers Voluntary or Location Nervous system
Involuntary control:
peripheral NS or
Autonomic NS?
Skeletal muscle
Striated, tubular, Somatic nervous
and multi nucleated Voluntary Skeletal system
Smooth muscle
Non-striates, Various organs,
spindle-shaped, and Involuntary Ex: GI tract, Autonomic NS
uninucleated airways, & blood
muscles
Cardiac muscle
Straited, branched
and uninucleated Involuntary Heart Autonomic NS
, 2. Muscle tissue components (layers of the muscle and coverings)
Level of Organization within a Skeletal Muscle/Components of Muscle Tissue
o Largest Structure to smallest structure (skeletal muscle, fascicle, muscle fibers,
myofibril, and filament)
1. Whole skeletal muscle, where a layer called epimysium is surrounding or
covering the whole muscle.
2. Fascicle: Tissue covering fascicle is perimysium, they are little bundles and
large enough to see with the naked eye.
3. Muscle fiber/muscle cell: fascicles are made up of different bundles and
those bundles are called muscle fibers, what covers the muscle fibers
endomysium
a. 3 connective tissue covering from outer to inner
i. Epimysium, perimysium, and endomysium
4. Myofibril: inside the muscle fibers, does not have any connective tissue
coverage.
5. Filament/ myofilament: Myofibril is made up of filaments, sometimes
myofilaments
a. There are 2 types of filaments within the muscle fibers
i. Actin: thin filament
ii. Myosin: thick filament
Definitions:
1. Origin: the attachment of a muscle’s tendon to the stationary bone.
2. Insertion: the attachment of the muscle’s other tendon to the moveable bone
3. Sarcomere: the basic functional units of myofibril. It extends from one Z disc to the next
Z disc.
4. Sarcolemma: the plasma membrane of a muscle cell. Where transverse tubules (t-
tubule) are attached to it and go to the sarcoplasmic reticulum.
5. A band: darker middle part of the sarcomere.
6. I band: a lighter, less dense area that contains the rest of the thin filaments but not thick
filaments, and a Z disc passes through the center of each I band
7. T-Tubules: open to the outside of the fiber, they are filled with interstitial fluid.
8. Elasticity: the ability of muscular tissue to return to its original length and shape after
contraction or extension.
9. Extensibility: the ability of muscular tissue to stretch, within limits, without being
damaged.
10. Contractility: the ability of muscular tissue to contract forcefully when stimulated by an
action potential.
11. Electrical Excitability: ability to respond to certain stimuli by producing electrical signals
called action potentials.
12. Sarcoplasmic Reticulum: a fluid-filled system of membranous sacs encircles each
myofibril.
13. Graded potential: used for short-distance communication only
14. Spatial summation: summation of postsynaptic potentials in response to stimuli that
occur at different locations in the membrane of a postsynaptic cell at the same time.
15. Temporal summation: summation of postsynaptic potentials in response to stimuli that
occur at the same location in the membrane of the postsynaptic cell but at
different times.
16. Agonist: an agent that binds to receptors and enhances or mimics the effect of a natural
neurotransmitter.
17. Antagonist: an agent that binds to and blocks neurotransmitter receptors
18. Synergist: contract and stabilize the intermediate joints, to prevent unwanted
movements at intermediate joints or to otherwise aid the movement of the prime
mover.
,Chapter 10:
1. Comparison of different muscle tissue types (identification, location, voluntary or
involuntary)
Types of Muscular Tissue
o Skeletal muscle: most skeletal muscles move the bones of the skeleton. It is striated
and works mainly in a voluntary manner. Its activity can be consciously controlled by
neurons that are part of the somatic voluntary division of the nervous system.
Function: Move bones
o Cardiac Muscle: forms most of the heart wall. It is also straited, but its action is
involuntary. Alternating contraction and relaxation of the heart is not controlled, rather
the heart beats because it is a natural pacemaker that initiates each contraction.
Autorhythmic: built-in rhythm.
Function: pump blood
o Smooth Muscle: located in the walls of hollow internal structures, such as blood vessels,
airways, and most organs on the abdominopelvic cavity. It is also found in the skin
attached to hair follicles. It is nonstriated and involuntary. Both cardiac and smooth
muscle are regulated by neurons that are part of the autonomic involuntary division of
the nervous system and by hormones released by endocrine gland.
Function: various functions for example peristalsis. Motion (construction of
blood vessels and airways propulsion of foods through gastrointestinal tract,
contraction of urinary bladder and gallbladder).
Fibers Voluntary or Location Nervous system
Involuntary control:
peripheral NS or
Autonomic NS?
Skeletal muscle
Striated, tubular, Somatic nervous
and multi nucleated Voluntary Skeletal system
Smooth muscle
Non-striates, Various organs,
spindle-shaped, and Involuntary Ex: GI tract, Autonomic NS
uninucleated airways, & blood
muscles
Cardiac muscle
Straited, branched
and uninucleated Involuntary Heart Autonomic NS
, 2. Muscle tissue components (layers of the muscle and coverings)
Level of Organization within a Skeletal Muscle/Components of Muscle Tissue
o Largest Structure to smallest structure (skeletal muscle, fascicle, muscle fibers,
myofibril, and filament)
1. Whole skeletal muscle, where a layer called epimysium is surrounding or
covering the whole muscle.
2. Fascicle: Tissue covering fascicle is perimysium, they are little bundles and
large enough to see with the naked eye.
3. Muscle fiber/muscle cell: fascicles are made up of different bundles and
those bundles are called muscle fibers, what covers the muscle fibers
endomysium
a. 3 connective tissue covering from outer to inner
i. Epimysium, perimysium, and endomysium
4. Myofibril: inside the muscle fibers, does not have any connective tissue
coverage.
5. Filament/ myofilament: Myofibril is made up of filaments, sometimes
myofilaments
a. There are 2 types of filaments within the muscle fibers
i. Actin: thin filament
ii. Myosin: thick filament
