Question

question 1 1 pts during a contraction, muscles are first excited before the contraction can occur. generate heat due to an aerobic respiration. all require involuntary control of muscle cells. must first be stimulated by hormones in the blood. topic: sec. 6.1 skill: understanding increase in length.

Explanation:

Muscle contraction is initiated by excitation - a nerve impulse stimulates the muscle fiber. Muscle contraction doesn't always generate heat via aerobic respiration immediately, not all muscles are involuntary (skeletal muscles are voluntary), and muscles are mainly stimulated by nerve impulses rather than just hormones in most cases, and during contraction, muscles shorten not lengthen.

Answer:

are first excited before the contraction can occur.