Question 1

When muscle is suddenly activated to perform contractions at a rapid rate, most of the ATP to fuel the first 3‒5 seconds of exercise comes from

Accepted Answer

A)  the aerobic breakdown of glycogen. 
B)  creatine phosphate hydrolysis. 
C)  anaerobic glycolysis. 
D)  ATP stored in the cell. 
A)  the aerobic breakdown of glycogen. 
B)  creatine phosphate hydrolysis. 
C)  anaerobic glycolysis. 
D)  ATP stored in the cell.

Question 2

Vertebrate skeletal muscle is characterized by thin-filament regulation of contraction while smooth muscle is characterized by thick-filament regulation. Explain the distinction between thin-filament and thick-filament regulation.

Accepted Answer

In skeletal muscle, actin and myosin are

Question 3

The two primary contractile proteins that underlie muscle movement are

Accepted Answer

A)  actin and tropomyosin. 
B)  myosin and troponin. 
C)  myosin and actin. 
D)  titin and nebulin. 
A)  actin and tropomyosin. 
B)  myosin and troponin. 
C)  myosin and actin. 
D)  titin and nebulin.

Question 4

Fast glycolytic muscle fibers depend on carbohydrate as a fuel, whereas slow oxidative fibers are capable of metabolizing carbohydrates, lipids, or amino acids. What is the physiological reason for this difference?

Accepted Answer

A)  Anaerobic glycolysis can produce ATP from glucose much more quickly than lipid or amino acid oxidation can take place. 
B)  The myosin in fast glycolytic fibers can only bind to glycogen. 
C)  Compared to fast glycolytic fibers, slow oxidative fibers need to metabolize a wider variety of fuels to meet a higher ATP demand. 
D)  Slow oxidative fibers need to metabolize lipid because they have less creatine kinase. 
A)  Anaerobic glycolysis can produce ATP from glucose much more quickly than lipid or amino acid oxidation can take place. 
B)  The myosin in fast glycolytic fibers can only bind to glycogen. 
C)  Compared to fast glycolytic fibers, slow oxidative fibers need to metabolize a wider variety of fuels to meet a higher ATP demand. 
D)  Slow oxidative fibers need to metabolize lipid because they have less creatine kinase.

Question 5

In tonic smooth muscle that contracts continuously for long periods, the highly efficient "latch state" depends on

Accepted Answer

A)  high myosin ATPase activity. 
B)  very slow turnover of ATP bound to myosin. 
C)  slow release of Ca2+ by troponin C. 
D)  high activity of myosin light-chain phosphatase. 
A)  high myosin ATPase activity. 
B)  very slow turnover of ATP bound to myosin. 
C)  slow release of Ca2+ by troponin C. 
D)  high activity of myosin light-chain phosphatase.

Question 6

The organization of actin and myosin into sarcomeres appear in

Accepted Answer

A)  only smooth muscle. 
B)  skeletal and smooth muscle. 
C)  only skeletal muscle. 
D)  skeletal and cardiac muscle. 
A)  only smooth muscle. 
B)  skeletal and smooth muscle. 
C)  only skeletal muscle. 
D)  skeletal and cardiac muscle.

Question 7

Tonic muscle

Accepted Answer

A)  is a form of smooth muscle. 
B)  has large amounts of sarcoplasmic reticulum. 
C)  is found primarily in postural muscles. 
D)  consumes no ATP. 
A)  is a form of smooth muscle. 
B)  has large amounts of sarcoplasmic reticulum. 
C)  is found primarily in postural muscles. 
D)  consumes no ATP.

Question 8

On the same set of axes, graph the relationship of velocity to force in two muscles of equal mass from the same animal. Muscle A contains predominantly fast glycolytic fibers, while muscle B contains predominantly slow oxidative fibers.

Accepted Answer

Answers will vary; example shown. The gr

Question 9

Suppose that muscle A is long with a narrow diameter and muscle B is short with a large diameter. Compared to muscle A, muscle B is capable of producing a _______ maximum force and a _______ maximum velocity.

Accepted Answer

A)  lower; lower 
B)  higher; higher 
C)  lower; higher 
D)  higher; lower 
A)  lower; lower 
B)  higher; higher 
C)  lower; higher 
D)  higher; lower

Question 10

Put the steps in neuromuscular junction synaptic transmission and EC-coupling in chronological order.
1. Myosin heads hydrolyze ATP during the cross-bridge cycle.
2. An EPSP is generated in the muscle cell.
3. An action potential is conducted along the sarcolemma.
4. Voltage-gated Na+ channels open in sarcolemma.
5. Ca²⁺ rises in the muscle cell cytoplasm.
6. Vesicles containing acetylcholine fuse with axon terminal membrane.
7. Tropomyosin rotates into groove of thin filament.
8. Ca²⁺ dissociates from troponin.
9. Motoneuron axon terminal are depolarized.
10. RyRs open.
11. Acetylcholine receptors open and conduct ions.
12. Ca²⁺+ binds to troponin C.

Accepted Answer

9-6-11-2-4

Question 11

The force‒velocity relationship for skeletal muscle indicates that a muscle

Accepted Answer

A)  produces maximum force when contracting at its maximum velocity. 
B)  shortens at maximum velocity when contracting against the maximum load it can move. 
C)  produces maximum power when contracting isometrically. 
D)  shortens at maximum velocity when contracting against no load. 
A)  produces maximum force when contracting at its maximum velocity. 
B)  shortens at maximum velocity when contracting against the maximum load it can move. 
C)  produces maximum power when contracting isometrically. 
D)  shortens at maximum velocity when contracting against no load.

Question 12

Smooth muscle cells possess which component?

Accepted Answer

A)  Sarcoplasmic reticulum 
B)  T-tubules 
C)  Multiple nuclei 
D)  Sarcomeres 
A)  Sarcoplasmic reticulum 
B)  T-tubules 
C)  Multiple nuclei 
D)  Sarcomeres

Question 13

List four factors that could allow a leg muscle in one animal to activate and relax more quickly than a leg muscle in another animal.

Accepted Answer

Possible factors include: higher levels

Question 14

The sarcomeres of vertebrate skeletal muscles are all about the same length, but squid have different sarcomere lengths in different muscles in the body. If all other factors are equal, the muscle with shorter sarcomeres will

Accepted Answer

A)  shorten more slowly. 
B)  shorten more rapidly. 
C)  generate more force. 
D)  generate less force. 
A)  shorten more slowly. 
B)  shorten more rapidly. 
C)  generate more force. 
D)  generate less force.

Question 15

A vertebrate motor unit consists of

Accepted Answer

A)  a single motor neuron and all of the muscle fibers that it innervates. 
B)  all of the muscles that contract to complete a particular body movement. 
C)  a particular muscle and all of its synergistic and antagonistic muscles. 
D)  all of the fibers of a particular fiber type in a given muscle. 
A)  a single motor neuron and all of the muscle fibers that it innervates. 
B)  all of the muscles that contract to complete a particular body movement. 
C)  a particular muscle and all of its synergistic and antagonistic muscles. 
D)  all of the fibers of a particular fiber type in a given muscle.

Question 16

The force produced by a smooth muscle cell could be increased by

Accepted Answer

A)  inhibition of myosin light-chain kinase. 
B)  inhibition of myosin light-chain phosphatase. 
C)  inhibition of calmodulin. 
D)  an increase in the amount of Ca2+ binding to troponin C. 
A)  inhibition of myosin light-chain kinase. 
B)  inhibition of myosin light-chain phosphatase. 
C)  inhibition of calmodulin. 
D)  an increase in the amount of Ca2+ binding to troponin C.

Question 17

A _______ is a type of _______ and connects muscle tissue to bone.

Accepted Answer

A)  sarcomere; connective tissue 
B)  sarcomere; contractile tissue 
C)  tendon; connective tissue 
D)  tendon; contractile tissue 
A)  sarcomere; connective tissue 
B)  sarcomere; contractile tissue 
C)  tendon; connective tissue 
D)  tendon; contractile tissue

Question 18

Muscle A has a volume of 200 cm3, a length of 20 cm, and a cross-sectional area of 10 cm2. Muscle B has a volume of 200 cm3, a length of 10 cm, and a cross-sectional area of 20 cm2. Which of the following statements about these muscles is true?

Accepted Answer

A)  Both muscles can produce the same power, but they will shorten at different speeds. 
B)  Both muscles will shorten at the same speed, but they can produce different amounts of power. 
C)  Both muscles can exert the same force, but one will shorten more quickly than the other. 
D)  Both muscles can produce the same power and the same force. 
A)  Both muscles can produce the same power, but they will shorten at different speeds. 
B)  Both muscles will shorten at the same speed, but they can produce different amounts of power. 
C)  Both muscles can exert the same force, but one will shorten more quickly than the other. 
D)  Both muscles can produce the same power and the same force.

Exam 20: Muscle

When muscle is suddenly activated to perform contractions at a rapid rate, most of the ATP to fuel the first 3‒5 seconds of exercise comes from

Vertebrate skeletal muscle is characterized by thin-filament regulation of contraction while smooth muscle is characterized by thick-filament regulation. Explain the distinction between thin-filament and thick-filament regulation.

The two primary contractile proteins that underlie muscle movement are

Fast glycolytic muscle fibers depend on carbohydrate as a fuel, whereas slow oxidative fibers are capable of metabolizing carbohydrates, lipids, or amino acids. What is the physiological reason for this difference?

In tonic smooth muscle that contracts continuously for long periods, the highly efficient "latch state" depends on

The organization of actin and myosin into sarcomeres appear in

Tonic muscle

On the same set of axes, graph the relationship of velocity to force in two muscles of equal mass from the same animal. Muscle A contains predominantly fast glycolytic fibers, while muscle B contains predominantly slow oxidative fibers.

Suppose that muscle A is long with a narrow diameter and muscle B is short with a large diameter. Compared to muscle A, muscle B is capable of producing a _______ maximum force and a _______ maximum velocity.

The force‒velocity relationship for skeletal muscle indicates that a muscle

Smooth muscle cells possess which component?

List four factors that could allow a leg muscle in one animal to activate and relax more quickly than a leg muscle in another animal.

The sarcomeres of vertebrate skeletal muscles are all about the same length, but squid have different sarcomere lengths in different muscles in the body. If all other factors are equal, the muscle with shorter sarcomeres will

A vertebrate motor unit consists of

The force produced by a smooth muscle cell could be increased by

A _______ is a type of _______ and connects muscle tissue to bone.

Muscle A has a volume of 200 cm3, a length of 20 cm, and a cross-sectional area of 10 cm2. Muscle B has a volume of 200 cm3, a length of 10 cm, and a cross-sectional area of 20 cm2. Which of the following statements about these muscles is true?

Animals and Environments: Function on the Ecological Stage

Molecules and Cells in Animal Physiology

Genomics, Proteomics, and Related Approaches to Physiology

Physiological Development and Epigenetics

Transport of Solutes and Water

Nutrition, Feeding, and Digestion

Energy Metabolism

Aerobic and Anaerobic Forms of Metabolism

The Energetics of Aerobic Activity

Thermal Relations

Food, Energy, and Temperature at Work: The Lives of Mammals in Frigid Places

Neurons

Synapses

Sensory Processes

Nervous System Organization and Biological Clocks

Endocrine and Neuroendocrine Physiology

Reproduction

Integrating Systems at Work: Animal Navigation

Control of Movement

Movement and Muscle at Work: Plasticity in Response to Use and Disuse

Introduction to Oxygen and Carbon Dioxide in Physiology

External Respiration: the Physiology of Breathing

Transport of Oxygen and Carbon Dioxide in Body Fluids With an Introduction to Acid- Base Physiology

Circulation

Oxygen, Carbon Dioxide, and Internal Transport at Work: Diving by Marine Mammals

Water and Salt Physiology: Introduction and Mechanisms

Kidneys and Excretion With Notes on Nitrogen Excretion

Water, Salts, and Excretion at Work: Mammals of Deserts and Dry Savannas

Water and Salt Physiology of Animals in Their Environments

Filters

Suppose that muscle A is long with a narrow diameter and muscle B is short with a large diameter. Compared to muscle A, muscle B is capable of producing a _ maximum force and a _ maximum velocity.

A _ is a type of _ and connects muscle tissue to bone.

Muscle A has a volume of 200 cm³, a length of 20 cm, and a cross-sectional area of 10 cm². Muscle B has a volume of 200 cm³, a length of 10 cm, and a cross-sectional area of 20 cm². Which of the following statements about these muscles is true?