Muscle Sytem Test Review

The enzyme acetylcholinesterase cause acetylcholine to

break down

The muscle that compresses the cheeks, as when pursing the lips and blowing forcefully, is the ___________

buccinator

Muscle cells

can only contract.

Active muscles generate _____________.

carbon dioxide and heat

During which phase is the stimulus frequency so high that the relaxation phase is eliminated?

complete tetanus

Which of the following muscles is named for its shape?

deltoid

A muscle________ contains a sarcolemma, sarcoplasm, myofilaments, and myofibrils.

fiber

Regarding muscle fiber elongation,

gravity may help lengthen a muscle fiber after elongation

Which of the following occurs when tension production rises to a peak and very brief periods of relaxation occur?

incomplete tetanus

Glycosis

is an anaerobic process.

"Anaerobic endurance"

is exemplified by contractions of fast muscle fibers

Calcium ions are released from the sarcoplasmic reticulum during the ___________ phase of contraction.

latent

Regarding lactic acid regulation, which cells in the body consume extra oxygen and produce ATP for the conversion of excess lactate absorbed from the blood back to glucose?

liver cells

The less-moveable end of a skeletal muscle is the

origin.

The additional oxygen required during the recovery period to restore the normal pre-exertion levels is called the

oxygen debt

A sheath of connective tissue surrounding a bundle of striated muscle fibers is called

perimysium

Muscle fascicles are separated by

perimysium

The area between Z lines is the

sarcomere

The terminal cisternae are structural muscle features of the

sarcoplasmic reticula

Which of the following statements describes how muscles help maintain homeostasis?

skeletal muscle contractions help maintain body temperature

Which statement regarding "heat loss" is true?

Muscle contractions play an important role in the maintenance of normal body temperature.

Which statement regarding the relaxation phase of muscle twitch is true?

Muscle tension falls to resting levels.

Which statement regarding isometric contractions is true?

The tension produced never exceeds the load.

The ____________ contains vesicles filled with acetylcholine

axon terminal

In response to action potentials arriving from the transverse tubules, the sarcoplasmic reticulum releases

calcium ions

Skeletal muscle fibers differ from "typical cells" in that these muscle fibers

hav emany nuclei

During activities requiring aerobic endurance,

most of the muscle's energy is produced in mitochondria

The skeletal muscle structure that actively shorten and are responsible for muscle fiber contractions are called

sarcomeres

The skeletal muscle store calcium ions in the terminal cisternae of the

sarcoplasmic reticulum

Choose the correct statement regarding motor units.

A motor neuron may control two or three muscle fibers of the eye.

Rigor mortis occurs at death due to lack of

ATP

After death, rigor mortis lasts until

ATP is produced

Which of the following is a stimulus for contraction in skeletal muscle?

Acetylcholine

Which of the following is one of the steps that ends a contraction?

Acetylcholine is broken down by acetylcholinesterase

Which of the following is characteristic of cardiac muscle?

Cardiac muscle cells are striated.

During moderate activity, which of the following is true regarding muscle metabolism?

Glucose and fatty acids are catabolized.

Which of the following sarcomere components is made up of protein that connect ​the central portions of each thick filament to its neighbors?

H band

Which of the following occurs when glycosis produces pyruvate faster than it can be used by the mitochondria?

Lactic acid is produced.

What is the acronym used for naming muscles. What does each letter represent? Give one example of a muscle that reflects each letter of the acronym.

Locations- tibialis anterior Action- abbductor longus Direction of fibers- rectus femoris Shape- deltoid Number of origins- triceps brachii Origin and insertion- sternoclidomastoid Relative size- gluteus maximus

Because Mary wants to enter a marathon, she decides to consult a trainer who happens to be a kinesiologist. The trainer advises her on what type of muscle fibers she needs to develop and how she should train for it. WHich type of muscle fibers are involved? Briefly explain the anatomy and physiology of the trainer's advice.

Marathons require aerobic endurance. Mary would want to develop her slow fibers for long-term endurance. She would achieve this by engaging in activities that involve long-term mild to moderately intense workouts involving mostly leg and postural muscles, such as jogging, biking, swimming, and core exercises. Repeated long-term stimulation will help the slow fibers develop more mitochondria and a higher concentration of aerobic enzymes as well as slightly increase the size and strength of the muscles (hypertrophy).

Which of the following is true about red muscles?

Red muscles are slower are slower than white muscles

Which of the following is an accurate characteristic of slow fibers?

Resisting slow muscle fibers contain oxygen reserves

Which of the following is an effect of aging on the muscular system?

Skeletal muscle fibers become smaller in diameter.

Which type of scenario is most likely?

Small motor units are recruited first.

While unloading the trunk of her car, Amy pulls a muscle. As a result, she has difficulty moving her arm. The attending physician in the emrgency room tells her that she injured her latissimus dorsi muscle. Knowing that the latissimus dorsi was a back muscle, Amy doesn;t understnad what the muscle has to do with her injured arm. Explain the involvement of the muscle in Amy's injury.

The latissimus dorsi allows her humerus to pull back and lift. It is one of the insertion points of her arm. When the latissimus dorsi contracts, it allows the arm to move.

Myofibrils are made primarily of

actin and myosin

The striated appearance of skeletal muscle results from

actin and myosin arrangement

When a calcium ion binds to troponin,

active sites on actin are exposed

Which of the following terms is a descriptive word for a muscle's action?

adductor

A resting muscle generates most of its ATP by

anaerobic respiration

Smooth muscle cells

are spindle-shaped

A layer of collagen fibers that surrounds an entire muscle is called

epimysium

Which of the following muscles functions to maintain an erect spinal column and head?

erector spinae

Fast fibers

have high glycogen reserves.

The term used to describe muscular growth in response to usage in

hypertrophy

Exhaustion of energy reserves or decline in pH due to production and dissociation of lactic acid causes

muscle fatigue

Which of the following occurs as a result of motor units in a particular muscle being always active even though their contractions do not produce enough movement to cause contractions?

muscle tone

Muscle whose names contain the root cervi- would be found in the

neck.

Which statement regarding skeletal muscle is true?

skeletal muscles contain blood vessels

A person whose genetic makeup makes him or her a better marathon runner than a sprinter probably has more ____________ in his or her leg muscles.

slow fibers

Non =striated, involuntary muscle is

smooth

As a skeletal muscle contraction is initiated, acetylcholine binding alters the motor end plate membrane's permeability to

sodium ions

Creatine phosphate serves to

supply energy to synthesize ATP

Acetylcholinesterase is found within the

synaptic cleft

What is the function of the transverse tubule?

to transmit electrical impulses to the cell's interior

During active-site exposure, calcium ions bind to which of the following?

troponin

Tropomyosin strands are held in position by which of the following?

troponin molecules

A single stimulus-contraction-relaxation sequence in a muscle fiber is known as a(n)

twitch