Question

(9/25/25) formative assessment assignment: chapter 6 the muscular system part 1 (suggested
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contraction of a skeletal muscle as a whole
graded responses
in skeletal muscles, the “all - or - none” law of muscle physiology applies to the muscle fiber, not to the whole muscle. it states that a muscle fiber will
contract to its fullest extent when it is (1.) adequately; it never partially contracts. however, the whole muscle reacts to stimuli with
graded responses, or different degrees of shortening, which generate different amounts of force. in general, graded muscle contractions can be
produced two ways: (1) by changing the (2.) of muscle stimulation and (2) by changing the number of muscle fibers being stimulated at
one time. next, let’s describe a muscle’s response to each of these.
muscle response to increasingly rapid stimulation
although muscle twitches (single, brief, jerky contractions) sometimes result from certain (3.) system problems, this is not the way our
muscles normally operate. in most types of muscle activity, nerve impulses are delivered to the muscle at a very rapid rate—so rapid that the muscle
does not get a chance to relax completely between stimuli. as a result, the effects of the successive contractions are “summed” (added) together,
and the (4.) of the muscle get stronger and smoother. the muscle exhibits unfused tetanus (tet’ah - nus), or incomplete tetanus. when the
muscle is stimulated so rapidly that no evidence of relaxation is seen and the contractions are completely smooth and sustained, the muscle is in
fused tetanus, or complete (5.), or in tetanic contraction* (figure 6.9).

○ 1. tetanus 2. stimulated 3. frequency 4. nervous 5. contractions

○ 1. contractions 2. tetanus 3. stimulated 4. frequency 5. nervous

○ 1. frequency 2. nervous 3. contractions 4. tetanus 5. stimulated

○ 1. stimulated 2. frequency 3. nervous 4. contractions 5. tetanus

○ 1. nervous 2. contractions 3. tetanus 4. stimulated 5. frequency

Explanation:

1. A muscle fiber contracts to its fullest extent when it is stimulated adequately, so the first blank is "stimulated".
2. Graded muscle contractions can be produced by changing the frequency of muscle stimulation, so the second blank is "frequency".
3. Muscle twitches sometimes result from certain nervous - system problems, so the third blank is "nervous".
4. The effects of successive contractions are summed and the contractions of the muscle get stronger and smoother, so the fourth blank is "contractions".
5. When the muscle is in fused tetanus, it is in complete tetanus or in tetanic contraction, so the fifth blank is "tetanus".

Answer:

1. stimulated
2. frequency
3. nervous
4. contractions
5. tetanus