Question 1

Which of the following events occurs during the lag phase of a muscle twitch?

Accepted Answer

A) Muscle fibers shorten. 
B) Cross-bridges form,move,release,and reform many times. 
C) The action potential is propagated from presynaptic to postsynaptic membrane. 
D) Calcium is pumped back into the sarcoplasmic reticulum. 
E) All of these events occur in the lag phase. 
A) Muscle fibers shorten. 
B) Cross-bridges form,move,release,and reform many times. 
C) The action potential is propagated from presynaptic to postsynaptic membrane. 
D) Calcium is pumped back into the sarcoplasmic reticulum. 
E) All of these events occur in the lag phase.

Question 2

Maureen is hiking in the cold,and to maintain homeostasis her body begins to

Accepted Answer

A)  increase heat loss from the skin. 
B)  release chemicals to initiate a high fever. 
C)  shiver. 
D)  reduce her blood pressure. 
E)  vasodilate vessels in her head and neck. 
A)  increase heat loss from the skin. 
B)  release chemicals to initiate a high fever. 
C)  shiver. 
D)  reduce her blood pressure. 
E)  vasodilate vessels in her head and neck.

Question 3

A lack of glycolytic enzymes within skeletal muscle cells would impair which type of ATP-yielding 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 4

What type of muscle tissue causes vasoconstriction?

Accepted Answer

A) skeletal muscle 
B) smooth muscle 
C) cardiac muscle 
A) skeletal muscle 
B) smooth muscle 
C) cardiac muscle

Question 5

Arrange these structures as they participate in excitation-contraction.

Accepted Answer

A) T tubules,sarcolemma,calcium ions,sarcoplasmic reticulum 
B) calcium ions,T tubules,sarcolemma,sarcoplasmic reticulum 
C) sarcolemma,T tubules,sarcoplasmic reticulum,calcium ions 
D) sarcoplasmic reticulum,calcium ions,T tubules,sarcolemma 
E) sarcolemma,sarcoplasmic reticulum,calcium ions,T tubules 
A) T tubules,sarcolemma,calcium ions,sarcoplasmic reticulum 
B) calcium ions,T tubules,sarcolemma,sarcoplasmic reticulum 
C) sarcolemma,T tubules,sarcoplasmic reticulum,calcium ions 
D) sarcoplasmic reticulum,calcium ions,T tubules,sarcolemma 
E) sarcolemma,sarcoplasmic reticulum,calcium ions,T tubules

Question 6

What is a triad?

Accepted Answer

A) a protein found along the groove of the F-actin double helix 
B) a T tubule and two adjacent terminal cisternae 
C) the combination of myosin heads with active sites on actin molecules 
D) the movement of myosin head while attached to actin myofilament 
E) after exercise,the oxygen taken in that exceeds the oxygen required for resting metabolism 
A) a protein found along the groove of the F-actin double helix 
B) a T tubule and two adjacent terminal cisternae 
C) the combination of myosin heads with active sites on actin molecules 
D) the movement of myosin head while attached to actin myofilament 
E) after exercise,the oxygen taken in that exceeds the oxygen required for resting metabolism

Question 7

Rigor mortis occurs after death because

Accepted Answer

A) cross-bridges form but can't release. 
B) calcium is actively transported back to the sarcoplasmic reticulum. 
C) anaerobic respiration is occurring. 
D) myosin levels decline at death. 
E) cross-bridges never form. 
A) cross-bridges form but can't release. 
B) calcium is actively transported back to the sarcoplasmic reticulum. 
C) anaerobic respiration is occurring. 
D) myosin levels decline at death. 
E) cross-bridges never form.

Question 8

Incomplete tetanus

Accepted Answer

A) is the time during which the tissue cannot respond again. 
B) results in complete and incomplete tetanus. 
C) is the condition in which the muscle fiber only partially relaxes between contractions. 
D) is the condition in which stimuli occur so rapidly that there are no intervening relaxations. 
E) is the constant tension produced by muscles for long periods of time. 
A) is the time during which the tissue cannot respond again. 
B) results in complete and incomplete tetanus. 
C) is the condition in which the muscle fiber only partially relaxes between contractions. 
D) is the condition in which stimuli occur so rapidly that there are no intervening relaxations. 
E) is the constant tension produced by muscles for long periods of time.

Question 9

The refractory period

Accepted Answer

A) is the time during which the tissue cannot respond again. 
B) results in complete and incomplete tetanus. 
C) is the condition in which the muscle fiber only partially relaxes between contractions. 
D) is the condition in which stimuli occur so rapidly that there are no intervening relaxations. 
E) is the constant tension produced by muscles for long periods of time. 
A) is the time during which the tissue cannot respond again. 
B) results in complete and incomplete tetanus. 
C) is the condition in which the muscle fiber only partially relaxes between contractions. 
D) is the condition in which stimuli occur so rapidly that there are no intervening relaxations. 
E) is the constant tension produced by muscles for long periods of time.

Question 10

Inflammation of the fibrous connective tissue resulting in stiffness and soreness is

Accepted Answer

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

Question 11

-What does "B" represent on the diagram?

Accepted Answer

A) threshold 
B) depolarization 
C) depolarization phase of action potential 
D) repolarization phase of action potential 
A) threshold 
B) depolarization 
C) depolarization phase of action potential 
D) repolarization phase of action potential

Question 12

Which of the following helps explain the increased tension seen in multiple wave summation?

Accepted Answer

A) increased motor unit recruitment 
B) increased concentration of calcium ions around the myofibrils 
C) exposure of more active sites on myosin myofilaments 
D) the breakdown of elastic elements in the cell 
E) decreased stimulus frequency 
A) increased motor unit recruitment 
B) increased concentration of calcium ions around the myofibrils 
C) exposure of more active sites on myosin myofilaments 
D) the breakdown of elastic elements in the cell 
E) decreased stimulus frequency

Question 13

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 14

The region of the sarcomere that contains both actin and myosin myofilaments is called the

Accepted Answer

A) I band. 
B) A band. 
C) Z disk. 
D) H zone. 
E) M line. 
A) I band. 
B) A band. 
C) Z disk. 
D) H zone. 
E) M line.

Question 15

What type of muscle tissue causes peristalsis?

Accepted Answer

A) skeletal muscle 
B) smooth muscle 
C) cardiac muscle 
A) skeletal muscle 
B) smooth muscle 
C) cardiac muscle

Question 16

The model that describes the contraction of the muscle is called the

Accepted Answer

A) contraction cycle. 
B) power stroke. 
C) sliding filament model. 
D) slipping fibril mechanism. 
E) paddle model. 
A) contraction cycle. 
B) power stroke. 
C) sliding filament model. 
D) slipping fibril mechanism. 
E) paddle model.

Question 17

Heather is watching a movie.What type of chemical pathway do her muscles depend upon at this time?

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 18

Curare blocks acetylcholine receptors at the motor end plate.This would result in

Accepted Answer

A) increased stimulation of the muscle. 
B) more acetylcholinesterase production. 
C) lack of calcium uptake by the muscle fiber. 
D) inability of the muscle fiber to respond to nervous stimulation. 
E) sustained contraction of the muscle. 
A) increased stimulation of the muscle. 
B) more acetylcholinesterase production. 
C) lack of calcium uptake by the muscle fiber. 
D) inability of the muscle fiber to respond to nervous stimulation. 
E) sustained contraction of the muscle.

Question 19

Multiple wave summation

Accepted Answer

A) is a time during which the tissue cannot respond again. 
B) results in complete and incomplete tetanus. 
C) is a condition in which the muscle fiber only partially relaxes between contractions. 
D) is a condition in which stimuli occur so rapidly that there are no intervening relaxations. 
E) is a constant tension produced by muscles for long periods of time. 
A) is a time during which the tissue cannot respond again. 
B) results in complete and incomplete tetanus. 
C) is a condition in which the muscle fiber only partially relaxes between contractions. 
D) is a condition in which stimuli occur so rapidly that there are no intervening relaxations. 
E) is a constant tension produced by muscles for long periods of time.

Question 20

The stretch of elastic components of a muscle adds to the increased tension during

Accepted Answer

A) incomplete tetanus. 
B) twitch. 
C) multiple wave summation. 
D) all or none response. 
E) none of these. 
A) incomplete tetanus. 
B) twitch. 
C) multiple wave summation. 
D) all or none response. 
E) none of these.

Exam 9: Muscular System: Histology and Physiology

Which of the following events occurs during the lag phase of a muscle twitch?

Maureen is hiking in the cold,and to maintain homeostasis her body begins to

A lack of glycolytic enzymes within skeletal muscle cells would impair which type of ATP-yielding process?

What type of muscle tissue causes vasoconstriction?

Arrange these structures as they participate in excitation-contraction.

What is a triad?

Rigor mortis occurs after death because

Incomplete tetanus

The refractory period

Inflammation of the fibrous connective tissue resulting in stiffness and soreness is

-What does "B" represent on the diagram?

Which of the following helps explain the increased tension seen in multiple wave summation?

Increased strength of a trained muscle is due to

The region of the sarcomere that contains both actin and myosin myofilaments is called the

What type of muscle tissue causes peristalsis?

The model that describes the contraction of the muscle is called the

Heather is watching a movie.What type of chemical pathway do her muscles depend upon at this time?

Curare blocks acetylcholine receptors at the motor end plate.This would result in

Multiple wave summation

The stretch of elastic components of a muscle adds to the increased tension during

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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