Deck 13: Physiology of the Muscular System

Question 1

Flexion at the knee involves ________.

A) isotonic contraction of both the hamstring group and the quadriceps femoris group
B) eccentric contraction of the hamstring group and concentric contraction of the quadriceps femoris group
C) concentric contraction of the hamstring group and eccentric contraction of the quadriceps femoris group
D) isometric contraction of the hamstring group and isotonic contraction of the quadriceps femoris group

Answer 1

C

Question 2

A period of sustained muscle contraction is called ________.

A) tetanus
B) lockjaw
C) incomplete tetanus
D) muscle tension

Answer 2

A

Question 3

Static flexibility is measured with a ________.

A) yard stick
B) protractor
C) ruler
D) goniometer

Answer 3

D

Question 4

After a period of intense exercise,the build-up of lactic acid leads to ________.

A) oxygen debt
B) glycolysis
C) the Cori cycle
D) muscle fatigue

Question 5

The range of motion at a joint is called ________.

A) static flexibility
B) flexibility
C) muscle fatigue
D) dynamic flexibility

Question 6

Isotonic muscle contractions differ from isometric contractions because isotonic contractions ________.

A) result in lengthening of the muscle
B) involve movement of the muscle and body structures
C) do not involve shortening of a muscle
D) result in shortening of the muscle

Question 7

How do dynamic and static flexibility differ?

A) Dynamic flexibility considers resistance to a motion as well as the difficulty of a movement.
B) Dynamic flexibility only measures range of motion.
C) Static flexibility considers resistance to a motion as well as the difficulty of a movement.
D) There is no difference between the two.

Question 8

If your lab partner measures the angle formed between your arm and your shoulder as you adduct your arm such that it crosses anterior to your torso,which type of flexibility is being measured?

A) static
B) dynamic
C) goniometer
D) muscle

Question 9

Production and accumulation of ________ in muscle cells leads to muscle fatigue.

A) lactic acid
B) ATP
C) glucose
D) glycogen

Question 10

Lifting a 25-lb barbell by flexing your forearm requires ________.

A) the biceps brachii to contract concentrically and the triceps brachii to contract eccentrically
B) eccentric contraction of both the biceps brachii and triceps brachii
C) the biceps brachii to contract eccentrically and the triceps brachii to contract concentrically
D) Isometric contraction of the biceps brachii and concentric contraction of the triceps brachii

Question 11

Using your hands and forearms to push against--but not move--a brick wall involves which of the following?

A) isotonic contraction
B) concentric contraction
C) isometric contraction
D) eccentric contraction

Question 12

The activation of increasing numbers of motor units is known as ________.

A) motor unit recruitment
B) muscle fatigue
C) muscle tension
D) threshold stimulus

Question 13

Extension at the knee involves ________.

A) concentric contraction of the hamstring group and eccentric contraction of the quadriceps femoris group
B) eccentric contraction of the hamstring group and concentric contraction of the quadriceps femoris group
C) isometric contraction of the hamstring group and isotonic contraction of the quadriceps femoris group
D) isotonic contraction of both the hamstring group and the quadriceps femoris group

Question 14

Which activity will result in the recruitment of the highest number of motor units?

A) lifting a 10-lb barbell
B) lifting a 2-lb barbell
C) lifting a 25-lb barbell
D) lifting a 5-lb barbell

Question 15

The speed of muscle contraction is ________ related to load.

A) indirectly
B) not
C) directly
D) inversely

Question 16

Why is it easier to lift an ink pen than it is to lift a 25-lb barbell?

A) It requires fewer motor units to lift the ink pen.
B) It takes more time for muscle tension to exceed the load of a light object than a heavy object.
C) The time for muscle tension to exceed load is not dependent on the mass of an object.
D) It takes less time for muscle tension to exceed the load of a heavy object than a light object.

Question 17

An individual's measured range of motion upon abduction of the right shoulder is 90 degrees and upon adduction is 120 degrees.Which of the following statements about range of motion is true?

A) The range of motion at the shoulder joint is above average for adduction and above average for adduction.
B) The range of motion at the shoulder joint is above average for each movement.
C) The range of motion at the shoulder joint is below average for both abduction and adduction.
D) The range of motion at the shoulder joint is below average for adduction and normal for adduction.

Question 18

Of the activities listed below,which relies primarily on isometric contractions?

A) answering the telephone
B) bending down to pick up a textbook
C) throwing a ball
D) sitting in an upright position

Question 19

A motor neuron and all the muscle fibers it controls is called a ________.

A) neuromuscular junction
B) threshold stimulus
C) motor nerve
D) motor unit

Question 20

Which of the following must occur for muscles to recover from fatigue?

A) ATP is produced via aerobic respiration.
B) Lactic acid builds up in the sarcolemma of muscle cells.
C) Muscle cells start to make ATP in anaerobic conditions.
D) Lactic acid is metabolized to pyruvate or glucose and ATP reserves are restored.