Question 1

Depolarization of the cell membrane occurs when there is a rapid influx (inflow) of

Accepted Answer

A)  potassium ions. 
B)  chloride ions. 
C)  calcium ions. 
D)  sodium ions. 
E)  amino acids. 
A)  potassium ions. 
B)  chloride ions. 
C)  calcium ions. 
D)  sodium ions. 
E)  amino acids.

Question 2

The capacity of a muscle cell to shorten forcefully is known as

Accepted Answer

A)  contractility. 
B)  excitability. 
C)  extensibility. 
D)  elasticity. 
E)  flexibility. 
A)  contractility. 
B)  excitability. 
C)  extensibility. 
D)  elasticity. 
E)  flexibility.

Question 3

Identify the statement concerning skeletal muscle that is true.

Accepted Answer

A)  It comprises about 20% of the body's weight. 
B)  It propels urine through the urinary tract. 
C)  Its function is largely under involuntary control. 
D)  It is a kind of connective tissue. 
E)  It is responsible for locomotion. 
A)  It comprises about 20% of the body's weight. 
B)  It propels urine through the urinary tract. 
C)  Its function is largely under involuntary control. 
D)  It is a kind of connective tissue. 
E)  It is responsible for locomotion.

Question 4

A lack of mitochondria within skeletal muscle would impair which ATP-yielding chemical process?

Accepted Answer

A)  anaerobic respiration 
B)  aerobic respiration 
C)  both anaerobic and aerobic respiration 
A)  anaerobic respiration 
B)  aerobic respiration 
C)  both anaerobic and aerobic respiration

Question 5

Physiological contracture

Accepted Answer

A)  occurs when muscles are resting. 
B)  is a condition in which cross-bridges cannot release. 
C)  is caused by an abundance of ATP in muscle fibers. 
D)  results when muscles are well exercised. 
E)  results when the neurotransmitter remains in the receptor. 
A)  occurs when muscles are resting. 
B)  is a condition in which cross-bridges cannot release. 
C)  is caused by an abundance of ATP in muscle fibers. 
D)  results when muscles are well exercised. 
E)  results when the neurotransmitter remains in the receptor.

Question 6

The length of the resting sarcomere is

Accepted Answer

A)  longer than the length of a contracted sarcomere. 
B)  shorter than the length of a contracted sarcomere. 
C)  the same length as a contracted sarcomere. 
D)  the same length as the muscle fiber. 
E)  the same length as the myofibril. 
A)  longer than the length of a contracted sarcomere. 
B)  shorter than the length of a contracted sarcomere. 
C)  the same length as a contracted sarcomere. 
D)  the same length as the muscle fiber. 
E)  the same length as the myofibril.

Question 7

The sites where a chemical substance is transmitted from the presynaptic terminal of an axon to the postsynaptic membrane of a muscle fiber are called

Accepted Answer

A)  neuromuscular junctions. 
B)  sarcomeres. 
C)  myofilaments. 
D)  Z disks. 
E)  cell body of neuron. 
A)  neuromuscular junctions. 
B)  sarcomeres. 
C)  myofilaments. 
D)  Z disks. 
E)  cell body of neuron.

Question 8

Lack of acetylcholinesterase in the synaptic cleft would result in

Accepted Answer

A)  a decrease in acetylcholine production by the motor neuron. 
B)  continuous stimulation of the postsynaptic membrane. 
C)  rapid degradation of acetylcholine. 
D)  relaxation of the muscle. 
E)  continuous stimulation of the presynaptic membrane. 
A)  a decrease in acetylcholine production by the motor neuron. 
B)  continuous stimulation of the postsynaptic membrane. 
C)  rapid degradation of acetylcholine. 
D)  relaxation of the muscle. 
E)  continuous stimulation of the presynaptic membrane.

Question 9

Which of the following statements concerning smooth muscle is true?

Accepted Answer

A)  It contains many sarcomeres. 
B)  Caveolae seem to take the place of the myofibrils. 
C)  A calcium-calmodulin complex initiates cross-bridge formation. 
D)  The cells are large and multinuclear. 
E)  It has a well developed sarcoplasmic reticulum. 
A)  It contains many sarcomeres. 
B)  Caveolae seem to take the place of the myofibrils. 
C)  A calcium-calmodulin complex initiates cross-bridge formation. 
D)  The cells are large and multinuclear. 
E)  It has a well developed sarcoplasmic reticulum.

Question 10

List the following structures in order from smallest to largest. (1) muscle fiber
(2) myofilament
(3) myofibril
(4) muscle fasciculus

Accepted Answer

A)  4, 2, 3, 1 
B)  2, 1, 4, 3 
C)  3, 1, 4, 2 
D)  2, 3, 1, 4 
E)  1, 2, 3, 4 
A)  4, 2, 3, 1 
B)  2, 1, 4, 3 
C)  3, 1, 4, 2 
D)  2, 3, 1, 4 
E)  1, 2, 3, 4

Question 11

Which of the following connective tissue layers is outside all the others?

Accepted Answer

A)  perimysium 
B)  endomysium 
C)  epimysium 
D)  paramysium 
E)  sarcolemma 
A)  perimysium 
B)  endomysium 
C)  epimysium 
D)  paramysium 
E)  sarcolemma

Question 12

In excitation-contraction coupling,

Accepted Answer

A)  calcium ions must bind with myosin to expose active sites on actin. 
B)  myosin heads bind to exposed active sites on actin. 
C)  cross-bridges form between myosin heads and calcium ions. 
D)  movement of the troponin-tropomyosin complex causes actin myofilaments to slide. 
E)  ATP binds to actin myofilaments. 
A)  calcium ions must bind with myosin to expose active sites on actin. 
B)  myosin heads bind to exposed active sites on actin. 
C)  cross-bridges form between myosin heads and calcium ions. 
D)  movement of the troponin-tropomyosin complex causes actin myofilaments to slide. 
E)  ATP binds to actin myofilaments.

Question 13

Tetanus of a muscle is thought to be caused by

Accepted Answer

A)  high calcium ion concentrations in the sarcoplasm. 
B)  the rapid movement of sodium ions back into the sarcoplasmic reticulum. 
C)  an increase in stimulus strength. 
D)  increased temperature in the active muscle. 
E)  decreased amounts of calcium ions in muscle tissue. 
A)  high calcium ion concentrations in the sarcoplasm. 
B)  the rapid movement of sodium ions back into the sarcoplasmic reticulum. 
C)  an increase in stimulus strength. 
D)  increased temperature in the active muscle. 
E)  decreased amounts of calcium ions in muscle tissue.

Question 14

In a contracted muscle, the A bands do narrow because the length of the myosin myofilaments changes,.

Accepted Answer

A) True 
 B)False

Question 15

The sarcolemma is the

Accepted Answer

A)  cell membrane of a muscle fiber. 
B)  cytoplasm of muscle cells. 
C)  structural and functional unit of the skeletal muscle cell. 
D)  contractile thread that extends the length of the muscle fiber. 
E)  protein strand composed of actin. 
A)  cell membrane of a muscle fiber. 
B)  cytoplasm of muscle cells. 
C)  structural and functional unit of the skeletal muscle cell. 
D)  contractile thread that extends the length of the muscle fiber. 
E)  protein strand composed of actin.

Question 16

-What does "D" represent on the diagram?

Accepted Answer

A)  myosin myofilament 
B)  actin myofilament 
C)  sarcomere 
D)  Z disk 
E)  cross-bridge 
A)  myosin myofilament 
B)  actin myofilament 
C)  sarcomere 
D)  Z disk 
E)  cross-bridge

Question 17

Increased strength of a trained muscle is due to

Accepted Answer

A)  an increased number of muscle fibers. 
B)  the nervous system's ability to recruit a large number of motor units simultaneously. 
C)  elimination of unnecessary enzymes and metabolic pathways. 
D)  elimination of all fat deposits. 
E)  elimination of unnecessary connective tissue. 
A)  an increased number of muscle fibers. 
B)  the nervous system's ability to recruit a large number of motor units simultaneously. 
C)  elimination of unnecessary enzymes and metabolic pathways. 
D)  elimination of all fat deposits. 
E)  elimination of unnecessary connective tissue.

Question 18

One cause of spastic paralysis might be

Accepted Answer

A)  inhibition of acetylcholine molecules. 
B)  blockage of acetylcholine receptors. 
C)  inhibition of acetylcholinesterase. 
D)  destruction of synaptic vesicles. 
E)  increase in the amount of acetylcholinesterase. 
A)  inhibition of acetylcholine molecules. 
B)  blockage of acetylcholine receptors. 
C)  inhibition of acetylcholinesterase. 
D)  destruction of synaptic vesicles. 
E)  increase in the amount of acetylcholinesterase.

Question 19

Which of the following correctly describes myoglobin's special function in muscle tissue?

Accepted Answer

A)  breaks down glycogen 
B)  synthesizes ATP 
C)  acts as a reservoir for oxygen 
D)  produces action potentials 
E)  stores glucose 
A)  breaks down glycogen 
B)  synthesizes ATP 
C)  acts as a reservoir for oxygen 
D)  produces action potentials 
E)  stores glucose

Question 20

The condition of painful, spasmodic contractions of muscles is referred to as

Accepted Answer

A)  cramps. 
B)  fibrositis. 
C)  fibromyalgia. 
D)  muscular dystrophy. 
E)  paralysis. 
A)  cramps. 
B)  fibrositis. 
C)  fibromyalgia. 
D)  muscular dystrophy. 
E)  paralysis.

Exam 9: Muscular System: Histology and Physiology

Depolarization of the cell membrane occurs when there is a rapid influx (inflow) of

The capacity of a muscle cell to shorten forcefully is known as

Identify the statement concerning skeletal muscle that is true.

A lack of mitochondria within skeletal muscle would impair which ATP-yielding chemical process?

Physiological contracture

The length of the resting sarcomere is

The sites where a chemical substance is transmitted from the presynaptic terminal of an axon to the postsynaptic membrane of a muscle fiber are called

Lack of acetylcholinesterase in the synaptic cleft would result in

Which of the following statements concerning smooth muscle is true?

List the following structures in order from smallest to largest. (1) muscle fiber (2) myofilament (3) myofibril (4) muscle fasciculus

Which of the following connective tissue layers is outside all the others?

In excitation-contraction coupling,

Tetanus of a muscle is thought to be caused by

In a contracted muscle, the A bands do narrow because the length of the myosin myofilaments changes,.

The sarcolemma is the

-What does "D" represent on the diagram?

Increased strength of a trained muscle is due to

One cause of spastic paralysis might be

Which of the following correctly describes myoglobin's special function in muscle tissue?

The condition of painful, spasmodic contractions of muscles is referred to as

The Human Organism

The Chemical Basis of Life

Cell Biology

Tissues

Integumentary System

Skeletal System: Bones and Bone Tissue

Skeletal System: Gross Anatomy

Joints and Movement

Muscular System: Gross Anatomy

Functional Organization of Nervous Tissue

Spinal Cord and Spinal Nerves

Brain and Cranial Nerves

Integration of Nervous System Functions

The Special Senses

Autonomic Nervous System

Functional Organization of the Endocrine System

Endocrine Glands

Cardiovascular System: Blood

Cardiovascular System: the Heart

Cardiovascular System: Blood Vessels and Circulation

Lymphatic System and Immunity

Respiratory System

Digestive System

Nutrition, Metabolism, and Temperature Regulation

Urinary System

Water, Electrolyte, and Acid-Based Balance

Reproductive System

Development, Growth, Aging, and Genetics

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