test 4

Question 1

The axon terminal releases acetylcholine into the synaptic cleft, which is received by receptors on the motor end plate. Which structure does this describe?

Answer 1

The neuromuscular junction of a skeletal muscle

Question 2

A volleyball player depends on the gastrocnemius muscles for plantar flexion, whereas a marathon runner depends more on the soleus muscles for the same action. What characteristic of the soleus muscles makes this so?

Answer 2

They make more use of aerobic respiration.

Question 3

Extensibility refers to the ability of a muscle to stretch.

Answer 3

True

Question 4

Extensibility refers to the ability of a muscle to stretch.

Answer 4

Z disc

Question 5

The rectus femoris is an example of what muscle shape?

Answer 5

Pennate

Question 6

A muscle twitch produces external tension and moves an object by shortening the muscles during the _________blank phase.

Answer 6

contraction

Question 7

In the patellar tendon reflex arc, the patellar ligament is stretched, which stretches the quadriceps femoris muscle of the thigh. This reflex will cause the quadriceps femoris to _________blank and the hamstrings to _________blank.

Answer 7

contract; relax

Question 8

To stimulate muscle contraction, acetylcholine is released from the _________blank into the synaptic cleft.

Answer 8

synaptic vesicles

Question 9

The tendon reflex is the inhibition of a muscle’s contraction that occurs when its tendon is excessively stretched.

Answer 9

True

Question 10

What is the primary function of the sarcoplasmic reticulum?

Answer 10

Calcium storage

Question 11

[T/F] Direct (fleshy) muscular attachments are more common than indirect muscular attachments.

Answer 11

False

Question 12

Which ion binds to troponin, causing it to change shape and exposing the biding sites for tropomyosin?

Answer 12

Ca+

Question 13

[T/F] In the sliding filament model, during muscle contraction actin (thin filaments) move towards the m-line.[T/F] In the sliding filament model, during muscle contraction actin (thin filaments) move towards the m-line.

Answer 13

true

Question 14

Which of the following neurotransmitters are found within the synaptic vesicles of the axon terminal?

Answer 14

acetylocholine

Question 15

What is the energy source for muscle contraction?

Answer 15

Adenosine Triphosphate (ATP)

Question 16

Which of the following best describe the composition of the “triad” within myofibrils?

Answer 16

One T-tubule and two terminal cisterns

Question 17

Which of the following BEST defines a motor unit?

Answer 17

Ca2+ is released from the sarcoplasmic reticulum.

Question 18

Which of the following are universal characteristics of muscle?

Answer 18

excitability, elasticity, conductivity

Question 19

What type of connective tissue forms the endomysium?

Answer 19

loose areolar

Question 20

Sarco:

Answer 20

“flesh”

Question 21

Titin

Answer 21

forms the elastic filament

Question 22

Troponin:

Answer 22

protein that helps position tropomyosin and binds Ca+ ions

Question 23

Actin:

Answer 23

thin filament, binding site for myosin

Question 24

Myosin:

Answer 24

thick filament, splits ATP

Question 25

What is the functional (contractile) unit of muscle tissue?

Answer 25

sarcomere

Question 26

Which of the following are also known as "muscle cells"?

Answer 26

muscle fiber

Question 27

Which of the following is NOT a factor that contributes to the force of muscle contraction?

Answer 27

Muscle fiber type

Question 28

What is the name of the connective tissue that encloses an individual muscle fiber?

Answer 28

Endomysium

Question 29

What are reflexes primarily characterized by?

Answer 29

Quick, involuntary, and stereotyped reactions

Question 30

Which of the following are true of slow oxidative (type I) fibers?

Answer 30

Abundant in postural muscles, Use aerobic respiration

Question 31

Which of the following is NOT a classification of muscle fasicle arrangment?

Answer 31

Active shortening of the muscle with no production of joint movement

Question 32

Which of the following do secondary afferent (sensory) nerve fibers within a muscle spindle detect?

Answer 32

degree of stretch

Question 33

What is a muscle spindle primarily responsible for?

Answer 33

Monitoring muscle length and movement

Question 34

Which of the following is NOT a factor when classifying levers in the human body?

Answer 34

degrees of freedom

Question 35

What initiates a reflex action?

Answer 35

A sensory input

Question 36

During a stretch reflex arc, which of the following occurs to the agonist muscle?

Answer 36

excitatory alpha motor neuron signal, resulting in contraction

Question 37

During a tendon reflex, what is the physiological purpose of inhibiting strong muscle contractions?

Answer 37

To protect the muscle and tendon from damage.

Question 38

Which of the following pathways produces the most ATP per cycle?

Answer 38

Aerobic pathway

Question 39

Which of the following statements are TRUE regarding fast oxidative fibers? (Choose all that apply)

Answer 39

They have a lot of mitochondria, They are best for sprinting and walking, They are red to pink in color

Question 40

[T/F] In a class one lever, the load is found in the center

Answer 40

False

Question 41

Which of the following is defined as a contraction elicited by a single stimulus ?

Answer 41

Muscle twitch

Question 42

Which of the following are believed to lead to muscle fatigue during high-intensity exercise? [choose all that apply]

Answer 42

K+ accumulation in the T tubules, ADP and P accumulation

Question 43

Which of the following BEST describe the role of an antagonist muscle?

Answer 43

Opposes the motion of the prime mover

Question 44

Which of the following best describes a [Golgi] tendon organ?

Answer 44

small, loose collagen fibers found near the musculotendinous junction

Question 45

Which of the following lever systems is most common in the human body?

Answer 45

Class three

Question 46

In a class I (one) lever which of the following best describes the location of the fulcrum?

Answer 46

between the load and effort

Question 47

What type of connective tissue forms the endomysium?

Answer 47

loose areolar

Question 48

During the cross-bridge cycle actin filaments slide closer to the M-line

Answer 48

true

Question 49

The axon terminal is in direct contact with a muscle fiber (sarcolemma)

Answer 49

False

Question 50

What is the primary function of the sarcoplasmic reticulum?

Answer 50

Calcium storage

Question 51

What is the functional (contractile) unit of muscle tissue?

Answer 51

sarcomere

Question 52

Which of the following ions is released during the excitation-contraction coupling phase?

Answer 52

Ca