Chapter 46 – The Musculoskeletal System
31. In order for a muscle to contract, calcium ions released from the sarcoplasmic reticulum
must bind to
32. Which of these muscles would you expect to have the greatest proportion of slow-twitch
fibers?
33. Impressive was a champion Quarter Horse stallion with a magnificent muscular physique,
a trait that he passed on to dozens of offspring. However, many of Impressive’s offspring
developed periodic muscular twitching that sometimes left the horses temporarily unable to
move. Some horses even died. As it turns out, Impressive’s award-winning physique was due
to a mutation in a single, protein-encoding gene, resulting in hyperexcitable muscle (which
contracts even in the absence of a stimulus from its motor neuron). Which is NOT a plausible
explanation for the identity of the abnormal muscle protein in Impressive and his offspring?
Clarify Question
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What is the key concept addressed by the question?