BackMr. Nasheed has cerebral palsy and suffers severe skeletal muscle spasms as a result of his condition. He is prescribed the drug dantrolene, which prevents the release of Ca2+ from the SR. Explain how this will treat his muscle spasms.
Michael had a nervous habit of chewing on the inner lining of his lip with his front teeth. The lip grew thicker and thicker from years of continual irritation. Michael's dentist noticed his greatly thickened lip, then told him to have it checked to see if the thickening was a tumor. A biopsy revealed hyperplasia, but no evidence of neoplasia. What do these terms mean? Did Michael have cancer of the mouth?
Why are the connective tissue wrappings of skeletal muscles important? Name these connective tissue coverings, beginning with the finest and ending with the coarsest.
a.
Why are the connective tissue wrappings of skeletal muscles important? Name these connective tissue coverings, beginning with the finest and ending with the coarsest.
b.
Compartment syndrome can result from all of the following except
(a) Compressing a nerve in the wrist
(b) Compartments swelling with blood due to an injury involving blood vessels
(c) Torn ligaments in a given compartment
(d) Pulled tendons in the muscles of a given compartment
(e) Torn muscles in a particular compartment
Which of the following statements about myofibrils is not correct?
(a) Each skeletal muscle fiber contains hundreds to thousands of myofibrils.
(b) Myofibrils contain repeating units called sarcomeres.
(c) Myofibrils extend the length of a skeletal muscle fiber.
(d) Filaments consist of bundles of myofibrils.
(e) Myofibrils are attached to the plasma membrane at both ends of a muscle fiber.
An action potential can travel quickly from one cardiac muscle cell to another because of the presence of
(a) Gap junctions
(b) Tight junctions
(c) Intercalated discs
(d) Both a and c
What three layers of connective tissue are part of each muscle? What functional role does each layer play?
How does cardiac muscle tissue contract without neural stimulation?
Muscle tone keeps muscles healthy. What is muscle tone, and what causes it? What happens to a muscle that loses its tone?
Identify the structures in the following figure.
<IMAGE>
a. ___
b. ___
c. ___
d. ___
e. ___
f. ___
g. ___
h. ___
Bill broke his leg in a football game, and after six weeks the cast is finally removed. As he steps down from the examination table, he loses his balance and falls. Why?
Your ability to lift that heavy couch would be increased by which type of exercise?
a. Aerobic
b. Endurance
c. Resistance
d. Swimming
The smooth muscle type found in the walls of digestive and urinary system organs and that exhibits gap junctions and pacemaker cells is:
a. Multi unit
b. Unitary
Compare skeletal, smooth, and cardiac muscles in regard to their microscopic anatomy, location and arrangement in body organs, and function in the body.