Skip to main contentExam 3: Muscles - Ch 8, 9, & 10

The maintenance of a resting membrane potential is due to three factors:

(1) The concentration of K+ (Click to select) inside outside the membrane is (Click to select) lower higher than that (Click to select) inside outside the membrane.(2) The concentration of Na+ (Click to select) inside outside the membrane is (Click to select) higher lower than that (Click to select) outside inside the membrane.(3) The membrane is (Click to select) less more permeable to K+ than Na+.

Indicate whether each statement is true or false.

1. Cardiac muscle is striated. (Click to select) True False 2. Each cardiac muscle cell contains multiple nuclei. (Click to select) True False 3. Intercalated disks are found between cardiac muscle cells. (Click to select) True False 4. Cardiac muscle cells are voluntarily controlled. (Click to select) True False

Indicate whether each statement is true or false.

1. During contraction, the myosin myofilaments shorten. (Click to select) True 2. During contraction, the actin myofilaments shorten. (Click to select) False 3. The sliding filament model explains how myofilaments slide past each other. (Click to select) True 4. The sliding of the myofilaments past each other cause the sarcomere to shorten. (Click to select) True

Indicate whether each statement is true or false

1. Each cycle of cross-bridge formation requires one ATP molecule. (Click to select) True 2. Energy stored in the head of a mysosin molecule is not released during cross-bridge movement. (Click to select) False 3. Movement of the myosin head causes the actin myofilament to slide. (Click to select) True 4. The myosin head breaks ATP into ADP and phosphate. (Click to select) True

Match the connective tissue with the skeletal muscle component that it surrounds.

1. Endomysium (Click to select) Fascicles Muscles Muscle fibers 2. Perimysium (Click to select) Fascicles Muscles Muscle fibers 3. Epimysium (Click to select) Fascicles Muscles Muscle fibers

Predict whether each activity would primarily utilize fast-twitch or slow-twitch muscle fibers.

1. Long-distance jogging (Click to select) Slow-twitch Fast-twitch 2. Weightlifting (Click to select) Fast-twitch Slow-twitch 3. Sprinting (Click to select) Slow-twitch Fast-twitch 4. Biking twenty miles on flat ground (Click to select) Fast-twitch Slow-twitch

Indicate whether each statement is true or false regarding action potentials and the all-or-none principle.

1. Once the threshold is reached, an action potential will proceed without stopping. (Click to select) True 2. The action potentials will be different in different parts of the cell. (Click to select) False 3. If threshold is not reached, an action potential will occur, but it will be weaker. (Click to select) False 4. If threshold is not reached, an action potential will not occur. (Click to select) True

Match each muscle with the characteristics they are named after.

1. Pectoralis major (Click to select) Location; Number of heads Location; Size Orientation of fasciculi; Location 2. Gluteus minimus (Click to select) Location; Number of heads Location; Size Orientation of fasciculi; Location 3. Triceps brachii (Click to select) Orientation of fasciculi; Location Location; Number of heads Location; Size 4. Rectus femoris (Click to select) Location; Size Location; Number of heads Orientation of fasciculi;

Match the muscle fiber type with its characteristics.

1. Respond rapidly to nervous system stimulation (Click to select) Fast-twitch Slow-twitch 2. Fatigue quickly (Click to select) Fast-twitch Slow-twitch 3. Contain large amounts of myoglobin (Click to select) Slow-twitch Fast-twitch 4. Break down ATP relatively slowly (Click to select) Fast-twitch Slow-twitch 5. High glycogen concentration (Click to select) Fast-twitch Slow-twitch 6. High aerobic capacity (Click to select) Slow-twitch Fast-twitch

Match each muscle with the characteristics they are named after.

1. Tibialis anterior (Click to select) Orientation of fasciculi; Location Shape; Location Shape Location 2. Transversus abdominis (Click to select) Orientation of fasciculi; Location Shape; Location Shape Location 3. Deltoid (Click to select) Orientation of fasciculi; Location Location Shape; Location Shape 4. Quadratus femoris (Click to select) Shape Shape; Location Orientation of fasciculi; Location Location

Match the types of movement with the correct description. 1.adduction 2.hyperextension 3.plantar flexion 4.flexion 5.dorsiflexion 6.extension 7. abduction

1. movement away from the midline of the body or medial plane 2.extension of a joint beyond the anatomical position 3. standing on toes 4. reducing the angle of the joint 5. foot lifted toward shin 6. increasing the angle of a joint 7. movement toward the midline of the body or medial plane

The range of motion determined by the joint's muscular contraction is (Click to select) therapeutic active passive , whereas (Click to select) active therapeutic passive range of motion requires some external force such as manipulation in therapy.

Active, passive

Which connective tissue wrapping separates individual muscle fibers?

Endomysium

Beginning in anatomical position, what movements of the forearm are involved in bending your elbow and then turning your forearm so that your palm faces the floor?

Flexion and pronation

Which muscle shape has muscle fibers that run the length of the muscle and taper at each end?

Fusiform

Which of these joints is correctly matched to the type of synovial joint?

Intercarpal - plane

Which of the following actions is caused by contraction of skeletal muscle?

Moving your feet in walking

Of the following muscles of the head, which one wraps around the orbits?

Orbicularis oris

Which of the following is not a function of the myosin heads?

Produce tropomyosin to facilitate binding to actin molecules

The muscle that is used to cross the legs is the

Sartorius

If a stimulus is strong enough to produce a depolarization that reaches (or exceeds) threshold, all of the permeability changes responsible for an action potential proceed without stopping.

TRUE

Which of the following statements concerning slow-twitch oxidative muscle fibers is false?

They are well adapted to anaerobic activity.

Which of the following muscles is named for its shape?

Trapezius

Myofibrils are composed of protein filaments called actin and myosin.

True

Thin myofilaments are _________ myofilaments, and thick myofilaments are _________ myofilaments.

actin; myosin

Of the following muscles of the thigh, the _________ is on the posterior side.

adductor magnus

Flexion of the forearm is an example of a/an _________ type of movement.

angular

Smooth muscle and cardiac muscle are similar in that they both

are under involuntary control.

The multiaxial joint in which the spherical end of one bone fits into the cuplike socket of the other bone is called a _________ joint.

ball-and-socket

Joints joined together by hyaline cartilage or fibrocartilage would be classified as _________ joints.

cartilaginous

The orbicularis oris muscle

causes crow's feet wrinkles.

Joints are classified structurally according to the _________ that binds them, and functionally according to their _________.

connective tissue; degree of motion

Muscle myofibrils

contain myosin and actin myofilaments

The H zone

contains only myosin myofilaments

Triangular muscles like the pectoralis major are also called _________ muscles.

convergent

The cycle of a mysosin molecule forming cross-bridges, moving, then releasing and returning to its original position is called

cross-bridge movement

During the _________ phase, the inside of the cell becomes positively charged, and during the _________ phase, the membrane potential returns to its resting value.

depolarization; repolarization

The major movement produced during quiet breathing is accomplished by the

diaphragm

The joint capsule of synovial joints consists of an outer _________ and an inner _________

fibrous layer; synovial membrane

The adductor longus is named for its

function and size

Which of the following joints is the least stable?

glenohumeral (shoulder) joint

Which of the following joint disorders is caused by increased uric acid in the blood?

gout

Hypertrophy means that there is a/an _________ in the size of the muscle fibers, and there is usually _________ muscle fibers.

increase; no change in the number of

The deep back muscle that assists with flexion of the vertebral column is the

intertransversarii

The electrical properties of cells are the result of

ion concentration differences across the plasma membrane.

Shivering

is a response of the nervous system to a high fever.

A fascicle

is surrounded by perimysium.

A waste product of anaerobic respiration in muscle cells is _________, which can then be used to make ATP through aerobic respiration pathways.

lactic acid

Eversion and plantar flexion is accomplished by muscles in the _________ leg compartment.

lateral

The _________ elevates the scapula.

levator scapulae

The length of the resting sarcomere is

longer than the length of a contracted sarcomere.

The point where the axon terminal synapses with the muscle fiber sarcolemma is called the

neuromuscular junction

During exercise, an individual experiences _________ due to aerobic respiration, and after exercise, this oxygen is replenished with _________

oxygen deficit; excess post-exercise oxygen consumption

When the palm faces posteriorly.

pronation

When an intramuscular injection is given in the anterior aspect of the thigh, the injection is in the

rectus femoris

The charge difference across the plasma membrane of an unstimulated cell is called the

resting membrane potential

In order for the excitation-contraction coupling to occur, the production of an action potential must occur within the __________ of a muscle fiber.

sarcolemma

What is a muscle cell membrane called?

sarcolemma

The synovial fluid in synovial joints consists of

serum filtrate hyaluronic acid proteins All of the choices are correct.

If body temperature drops, muscles respond by contracting rapidly in order to produce heat, a process known as

shivering

Hypertrophy of skeletal muscles from weightlifting is caused by an increase in the

size of muscle fibers.

Depolarization of the cell membrane occurs when there is a rapid influx (inflow) of

sodium ions.

The _________ muscle is the prime mover for flexion of the head at the neck.

splenius capitis

Each presynaptic terminal contains _________, which contain the neurotransmitter _________ that, when released, cause ligand-gated Na+ channels to open in the motor end-plate. This causes _________ in the muscle cell.

synaptic vesicles; acetylcholine; depolarization

When you "pull your tummy in" and compress your abdomen, you use the rectus abdominis, external abdominal oblique, internal abdominal oblique, and transversus abdominis muscles. This is an example of muscles working as

synergists

The plasma membrane of an excitable cell is more permeable to potassium ions because

there are more leak channels for K+ than Na+.

Myosin is also known as the

thick myofilament

A muscle fiber will respond to a stimulus when that stimulus reaches the _________ level.

threshold