CAMPBELL BIOLOGY:CONCEPTS & CONNECTIONS
3rd Edition
ISBN: 9781323464175
Author: Pearson
Publisher: PEARSON C
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Textbook Question
Chapter 30, Problem 9TYK
Muscle A and muscle B have the same number of fibers, but muscle A is capable of more precise control than muscle B. Which of the following is likely to be true of muscle A? (Explain your answer.)
a. It is controlled by more neurons than muscle B.
b. It contains fewer motor units than muscle B.
c. It is controlled by fewer neurons than muscle B.
d. It has larger sarcomeres than muscle B.
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To demonstrate muscle fatigue, a student held an 8 lb dumbbell in her hand and abducted her arm parallel to the floor. After 45 seconds, she has having difficulty holding that position so she rotated her hand 90 degrees. This allowed her to hold the dumbbell in position for an additional 20 seconds. Which of the following is the best explanation for this?
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C.
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When a higher voltage is applied to the skeletal muscle, the force of contraction _____ and recruitment of more motor units occurs called ________ summation.
A. increases, spatial
B. increases, temporal
C. decreases, temporal
D. decreases, spatial
Which of the following would be recruited in a muscle stimulation when contractile strength increases?
A) Many small motor units with the ability to stimulate other motor units
B) Motor units with the longest muscle fibers
C) Motor units with larger, less excitable neurons
D) Large motor units with small, highly excitable endurance
Chapter 30 Solutions
CAMPBELL BIOLOGY:CONCEPTS & CONNECTIONS
Ch. 30 - Complete this concept map on animal movement.Ch. 30 - A humans internal organs are protected mainly by...Ch. 30 - Arm muscles and leg muscles are arranged in...Ch. 30 - Gravity would have the least effect on the...Ch. 30 - Prob. 5TYKCh. 30 - Prob. 6TYKCh. 30 - When a dog is running fast, its body position is...Ch. 30 - What is the role of calcium in muscle contraction?...Ch. 30 - Muscle A and muscle B have the same number of...Ch. 30 - Prob. 10TYK
Ch. 30 - Prob. 11TYKCh. 30 - Prob. 12TYKCh. 30 - Prob. 13TYKCh. 30 - Describe how you bend your arm, starting with...Ch. 30 - Prob. 15TYKCh. 30 - Drugs are often used to relax muscles during...Ch. 30 - An earthworms body consists of a number of...Ch. 30 - When a person dies, muscles become rigid and fixed...Ch. 30 - SCIENTIFIC THINKING Imagine you have a friend who...
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