Showing posts with label Muscles and Muscle Tissue. Show all posts
Showing posts with label Muscles and Muscle Tissue. Show all posts

An individual has just ingested a chemical that binds irreversibly to the ACh receptors in the sarcolemma. By itself it does not alter membrane potential, yet prevents normal neurotransmitter binding. Ignoring the effects on any other system, the consequence to skeletal muscle would be ________.

An individual has just ingested a chemical that binds irreversibly to the ACh receptors in the sarcolemma. By itself it does not alter membrane potential, yet prevents normal neurotransmitter binding. Ignoring the effects on any other system, the consequence to skeletal muscle would be ________. 




A) irreversible contraction as soon as the first nervous stimulation reached the sarcolemma
B) no contraction at all by nervous mechanisms
C) contraction if stimulated by an external electrode
D) no contraction at all by nervous mechanisms, but contraction if stimulated by an external electrode




Answer: D

Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped ________.

Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped ________. 




A) cross bridge attachment would be optimum because of all the free binding sites on actin
B) no muscle tension could be generated
C) maximum force production would result since the muscle has a maximum range of travel
D) ATP consumption would increase since the sarcomere is "trying" to contract




Answer: B

Three discrete types of muscle fibers are identified on the basis of their size, speed, and endurance. Which of the following athletic endeavors best represents the use of red fibers?

Three discrete types of muscle fibers are identified on the basis of their size, speed, and endurance. Which of the following athletic endeavors best represents the use of red fibers? 



A) a sprint by an Olympic runner
B) a long, relaxing swim
C) playing baseball or basketball
D) mountain climbing



Answer: B