Lesson 21.3: Vocabulary I Name Class Date
Match the vocabulary word with the proper definition.
Definitions
1. muscle tissue that is attached to bone
2. long, thin muscle cell that has the ability to contract, or shorten
3. theory that explains muscle contraction by the sliding of myosin filaments over
actin filaments within muscle fibers
4. tough connective tissue that attaches skeletal muscle to bones of the skeleton
5. human body system that includes all the muscles of the body
6. organs composed mainly of muscle cells
7. the region between two Z lines
8. involuntary, nonstriated muscle that is found in the walls of internal organs
such as the stomach
9. organelles contained within each muscle fiber
10. involuntary, striated muscle found only in the walls of the heart
11. tiny structures within the myosin filaments, that can attach to actin filaments
Terms
a. cardiac muscle
b. cross bridges
c. muscle fiber
d. muscles
e. muscular system
f. myofibril
g. sarcomere
h. skeletal muscle
i. sliding filament theory
j. smooth muscle
k. tendon