Quiz: Muscles, Chapter 9

Question 1

A sarcomere is the length between two…

Answer 1

Z discs

Question 2

The contractile proteins in the I band…

Answer 2

Only actin filaments

Question 3

The contractile proteins in the A band…

Answer 3

Both actin and myosin

Question 4

Thick filament; Thin filament…

Answer 4

Myosin; Actin

Question 5

Role of tropomyosin in skeletal muscles…

Answer 5

Serves as a contraction inhibitor by blocking the myosin binding sites on the actin molecules

Question 6

Most skeletal muscles contain…

Answer 6

A mixture of fiber types

Question 7

Fatigued muscle cells that recover rapidly are the products of…

Answer 7

Intense exercise of short duration

Question 8

The strongest muscle contractions are normally achieved by…

Answer 8

Increasing the stimulation up to the maximal stimulus

Question 9

Excitation-contraction coupling directly requires…

Answer 9

Calcium and ATP

Question 10

Factor that affects the velocity and duration of muscle contraction…

Answer 10

Load on the fiber

Question 11

Myoglobin’s purpose in muscle cells…

Answer 11

Stores oxygen

Question 12

Structure in skeletal muscle cells that stores calcium…

Answer 12

Sarcoplasmic Reticulum

Question 13

Excess postexercise oxygen consumption represents…

Answer 13

Difference between the amount of oxygen needed for totally aerobic muscle activity and the amount actually used

Question 14

Period during which the neurotransmitter is released by exocytosis, diffuses across the synaptic cleft, and binds to its receptors…

Answer 14

Latent period

Question 15

Creatine phosphate functions in the muscle cell by…

Answer 15

Storing energy that will be transferred to ADP to resynthesize ATP

Question 16

Major function of the sarcoplasmic reticulum in muscle contraction…

Answer 16

Regulation of intracellular calcium concentration

Question 17

Responsible for the striated appearance of skeletal muscle cells…

Answer 17

The arrangement of myofilaments

Question 18

During muscle contraction, myosin cross bridges attach to…

Answer 18

Actin filaments

Question 19

Wrapping that surrounds the individual muscle cell…

Answer 19

Endomysium

Question 20

Aponeurosis refers to…

Answer 20

A sheetlike indirect attachment to a skeletal element

Question 21

Oxygen-binding protein found in muscle cells is…

Answer 21

Myoglobin

Question 22

Contractile units of skeletal muscles…

Answer 22

Myofibrils

Question 23

Functional unit of skeletal muscles…

Answer 23

Sarcomeres

Question 24

Functional role of T tubules…

Answer 24

Enhance cellular communication during muscle contraction

Question 25

Role of calcium ions in muscle contraction...

Answer 25

Bind to regulatory sites on troponin to remove contraction inhibition

Question 26

During exercise, when there is insufficient oxygen to completely break down pyruvic acid for energy, the pyruvic acid is converted to...

Answer 26

Lactic acid

Question 27

When a muscle is unable to respond to stimuli temporarily, it is in its...

Answer 27

Refractory period

Question 28

In an isotonic contraction, the muscle...

Answer 28

Changes in length and moves the "load"

Question 29

Sequence of events for muscle contractions...

Answer 29

Motor neuron action potential, neurotransmitter release, muscle cell action potential, release of calcium ions from SR, ATP-driven power stroke, sliding of myofilaments

Question 30

Muscle tone is...

Answer 30

A state of sustained partial contraction

Question 31

Sliding filament model of contraction involves...

Answer 31

Actin and myosin sliding past each other and partially overlapping

Question 32

Prevents ACh in the synaptic cleft from continuing to stimulate contraction after nervous stimulation stops...

Answer 32

Acetylcholinesterase destroying the ACh

Question 33

In an isometric contraction, the muscle...

Answer 33

Increases tension without changing in length

Question 34

During isotonic contraction, muscle tension...

Answer 34

Remains relatively constant

Question 35

Most distinguishing characteristic of muscle tissue...

Answer 35

Its ability to transform chemical energy into mechanical energy

Question 36

Part of the sarcolemma that contains acetylcholine receptors

Answer 36

Motor end plate

Question 37

Hypothetically, if a muscle were stretched to the point where thick and thin filaments no longer overlapped...

Answer 37

No muscle tension could be generated