Ch 11: Muscular Tissue
1. In terms of muscle tissue, what is meant by
a. Excitability
when stimulated by chemical signals, stretch, and other stimuli, muscle cells respond w
electrical changes; ability to respond to stimuli
b. Contractility
the ability of muscle cells to forcefully shorten
c. Extensibility
ability of a muscle to extend to a predetermined endpoint
d. Elasticity
ability to stretch a muscle to reach its full range of movement without
restriction
2. Which germ layer does muscle come from?
mesoderm
3. Why is a muscle cell multinucleated?
they are formed from the fusion of embryonic myoblasts; they consists of several
cells that have fused together
4. What are the three types of muscle tissue found in the human body?
skeletal, smooth, and cardiac
a. Know the “Microscopic appearance and features” of the three muscle
tissue types.
Skeletal muscle tissue fibers are long, cylindrical, multinucleated, and striated and under
voluntary control. Attached to bones by tendons and can be 30 cm long, even though they
are usually 2 to 3 cm in length
, Smooth muscle tissue fibers are spindle shaped, have a single centrally located nucleus
and lack striations.
Cardiac muscle tissue fibers exist in the heart only, responsible for heart pumping and
blood circulating; striated, connected by intercalated discs, uninucleated
5. Know the CT coverings of muscle (epi-, peri-, endo-mysium) and their
location.
Epimysium ~ a sheath of fibrous elastic tissue surrounding a muscle
protects muscle from friction against other bones
Perimysium ~ a sheath of CT surrounding a bundle of muscle fibers
provides structural support to muscles.
Endomysium ~ a sheath that surrounds individual muscle fibers
separates single muscle fibers from one another.
6. What is a fascicle?
a bundle of muscle fibers (also called myocytes) bound together; provides pathways for
the passage of blood vessels.
● Where do tendons come from?
○ epi-, peri-, and endomysium
7. How are epi-, peri-, and endomysium involved in tendon formation?
All three CT layers will fuse together to form tendons
8. What is aponeurosis?
Flat tendon attached to flat muscles (ex. latissimus dorsi is a flat muscle)
9. What is fascia?