A&P (Ch. 10 muscle tissue) w/prac questions

Regarding muscle fiber elongation,

gravity may help lengthen a muscle fiber after elongation.

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

hypertrophy.

(Structural Components of a Skeletal Muscle Fiber) Structure E is the

sarcolemma.

The terminal cisternae are structural features of the

sarcoplasmic reticula.

(Structural Components of a Skeletal Muscle Fiber) Structure C is the

sarcoplasmic reticulum.

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

sarcoplasmic reticulum.

The insertion of the anterior part of the frontalis muscle is the

skin of the eyebrow and the bridge of the nose.

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

sodium ions.

Which muscle is not attached in some way to the scapula?

sternocleidomastoid

(Structural Components of a Skeletal Muscle Fiber) Structure B

stores calcium.

Creatine phosphate serves to

supply energy to synthesize ATP.

Acetylcholinesterase is found within the

synaptic cleft.

Each myofibril consists of approximately ________ sarcomeres.

10,000

The stiffness that occurs at death, when actin and myosin molecules stay linked to each other in a contracted state, is due to a lack of

ATP.

The enzyme acetylcholinesterase causes acetylcholine to

break down.

The deltoid acts to

abduct the arm.

Why do individual muscle twitches have to be added together, as in summation or tetanus?

Multiple twitches add up to an increase in muscle fiber tension, which increases the strength of the muscle.

The striated appearance of skeletal muscle results from

actin and myosin arrangement.

(Structural Components of a Skeletal Muscle Fiber) Structure I is composed of

actin and myosin.

Myofibrils are made primarily of

actin and myosin.

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

adductor

A resting muscle generates most of its ATP by

aerobic respiration.

Smooth muscle cells

are spindle-shaped.

The ________ contains vesicles filled with acetylcholine.

axon terminal

You are lying on the floor with your feet flat and your knees up practicing your abdominal crunches. You raise your upper body to the ceiling, up and down. What muscles are you using to the greatest extent?

transverse abdominis

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

calcium ions.

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

epimysium.

Which muscle would not move the scapula?

erector spinae

Which muscle(s) would produce a twisting of the upper body?

external and internal oblique muscles

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

muscle fatigue.

(Structural Components of a Skeletal Muscle Fiber) Structure J represents a

myofibril.

Looking at the muscle name sternocleidomastoid, you would identify that this muscle is located in the area of the

neck.

The less-movable 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.

Nonstriated, involuntary muscle is

smooth

The heart has to be able to regulate its contractions. Heart muscle, unlike skeletal muscle, cannot go into a tetanus. This is because

the heart muscle has to be able to consistently contract and pump blood in a controlled fashion.

Which muscle extends the elbow during the action of push-ups?

triceps brachii

Which muscle is not part of the rotator cuff set of muscles?

biceps brachii

The muscle that would be used to blow air into a trumpet or a clarinet is the

buccinator.

The active sites on actin molecules are usually covered up by other molecules. What is the critical material required to uncover the active sites on the actin molecules that will then bind to myosin heads?

calcium

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? A) pectoralis major B) biceps brachii C) deltoid D) erector spinae E) tibialis anterior

deltoid

A muscle that inserts on the radial tuberosity or the ulnar tuberosity is most likely involved in

elbow flexion.

Which of the following describes the action of the trapezius?

elevates, adducts, depresses, or rotates the scapula

Which of the following muscles functions to maintain an erect spinal column and head? A) erector spinae B) biceps brachii C) triceps brachii D) rectus femoris E) biceps femoris

erector spinae

A muscle ________ contains a sarcolemma, sarcoplasm, myofilaments, and myofibrils.

fiber

Fast fibers

have high glycogen reserves.

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

have many nuclei.

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

incomplete tetanus

"Anaerobic endurance"

is exemplified by contractions of fast muscle fibers.

Which of the following inserts into the intertubercular groove of the humerus and acts to extend, adduct, and rotate the shoulder?

latissimus dorsi

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

Which of the following is a muscle that originates from the zygomatic arch and functions in elevating the mandible?

masseter

(Structural Components of a Skeletal Muscle Fiber) The structures labeled F are the

mitochondria.

During activities requiring aerobic endurance,

most of the muscle's energy is produced in mitochondria.

The specialized sarcolemma that contains acetylcholine receptors is the

motor end plate.

Neurotransmitters that cause skeletal muscle contraction are normally stored in

motor neuron axon terminals.

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 contraction?

muscle tone

After death, rigor mortis lasts until

myofilaments are broken down.

(Structural Components of a Skeletal Muscle Fiber) Structure G is composed of

myosin.

The difference in the action when comparing the biceps brachii to the flexor carpi radialis, is

one muscle flexes the hand at the wrist and the other flexes the entire forearm.

In infants, which muscle allows for the mouth to form a tight fit around the nipple during suckling at the breast?

orbicularis oris

The muscle that originates from the superior surface of the pubis around the symphysis is the

rectus abdominis.

Botulism

results from a bacterial toxin that prevents the release of acetylcholine at the axon terminals.

The area between Z lines is the

sarcomere

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

The muscle that inserts on the coronoid process of the mandible is the

temporalis.

(Structural Components of a Skeletal Muscle Fiber) The triad, seen as structure D, is composed of

the cisterna of the sarcoplasmic reticulum along with the T tubules.

Regarding a skeletal muscle fiber, wherever a T-tubule encircles a myofibril, the tubule is tightly bound to

the sarcoplasmic reticulum.

(Structural Components of a Skeletal Muscle Fiber) Structure H is the

thin myofilament.

What is the function of the transverse tubule?

to transmit electrical impulses to the cell's interior

Which muscle inserts on the clavicle and the acromion and spine of the scapula?

trapezius

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.

Smooth muscle

uses primarily aerobic metabolism.

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.

(Structural Components of a Skeletal Muscle Fiber) Label A is pointing to

T tubules.

Which statement regarding isometric contractions is true? A) Tension rises during a contraction. B) The skeletal muscle's length changes. C) The tension produced never exceeds the load. D) Tension remains at a constant level until relaxation occurs. E) Examples are walking and running.

The tension produced never exceeds the load.

Which of the following is the origin of the pectoralis minor?

anterior surfaces of ribs 3-5

Muscle cells

can only contract.

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

latent

Which of the following inserts into a tendinous sheet, rather than a bone?

palmaris longus

Which of the following originates from the cartilages of ribs 2-6, the sternal body, and the clavicle?

pectoralis major

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

perimysium

Muscle fascicles are separated by

perimysium

Place these steps of muscle contraction in the correct order. 1. Action potential is generated along the sarcolemma 2. Nerve impulse arrives at synapse 3. Calcium is released into muscle cell cytoplasm 4. Acetylcholine is produced 5. Actin and myosin molecules continuously cross-link, with actin molecules being pulled inward

2, 4, 1, 3, 5

Which of the following is true about red muscles?

Red muscles are slower than white muscles.

Upon the nerve impulse arriving at the axon terminal,

acetylcholine is released.

Glycolysis

is an anaerobic process.

The region of a sarcomere containing myosin, going from one end of the myosin molecules to the other end of the myosin molecules, is the

A band.

Choose the correct statement regarding motor units.

A motor neuron may control only two or three muscle fibers of the eye muscle(s).

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

Glucose and fatty acids are catabolized.

The area of the sarcomere that is the light region between two successive A-bands is the

I band.

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

Lactic acid is produced.

Which statement regarding "heat loss" is true? A) Muscle activity does not generate heat. B) Shivering in a cold environment results in higher levels of heat loss. C) When skeletal muscles are contracting at peak levels, body temperature drops. D) Heat loss is reduced when blood flow to the skin increases. E) Muscle contractions play an important role in the maintenance of normal body temperature.

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

Which statement regarding the relaxation phase of a muscle twitch is true? A) The phase begins at stimulation and typically lasts about two milliseconds. B) Muscle tension falls to resting levels. C) The action potential sweeps across the sarcomere during this period. D) Tension rises to a peak. E) Cross-bridges are interacting with active sites on actin filaments throughout this period.

Muscle tension falls to resting levels.

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

Resting slow muscle fibers contain oxygen reserves, bound to myoglobin.

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

Skeletal muscle contractions help maintain body temperature.

Which statement regarding skeletal muscle is true? A) Skeletal muscles are directly, but not indirectly, attached to bones. B) Skeletal muscles do not contain connective tissue. C) Skeletal muscles do not maintain body temperature. D) Skeletal muscles do not contain nervous tissue. E) Skeletal muscles contain blood vessels.

Skeletal muscles contain blood vessels.