Anatomy quiz 2

Mike falls off his skateboard and sprains his ankle. Which of the following most likely occurs with this type of accident?

A ligament is stretched and collagen fibers in the ligament are damaged.

he characteristic muscle stiffness associated with rigor mortis is due to the inability of myosin filaments to detach from the active site on actin filaments. What molecule is essential for this detachment?

ATP

How would the loss of acetylcholinesterase from the motor end plate affect skeletal muscle?

It would cause muscles to stay contracted.

Which of the following occurs when the articular cartilage is damaged?

Normal synovial joint function is unable to continue. The exposed surface appears rough. Friction in the joint increases. The matrix begins to break down.

Which of the following explains the occurrence of a hip fracture rather than a hip dislocation?

Stress gets transferred from head of femur to the diaphysis via the thin neck.

Identify the incorrect statement about a single motor unit.

The more neurons involved, the more powerful the contraction.

The soleus muscle is very red in color. Which of these statements about soleus muscle fibers is FALSE?

They are large in diameter.

Why do the disease tetanus and the normal sustained muscle contraction called tetanus share the same name?

They both eliminate the relaxation phase in the affected muscle fibers.

The flava ligament is

a paired ligament that connect the laminae of adjacent vertebrae.

Which of the following is important to increasing efficiency in tension production?

a shortened relaxation phase

The cytoplasm of the neuromuscular terminal contains vesicles filled with molecules of the neurotransmitter

acetylcholine.

Which of the following situations could contribute to prolonged muscle contraction?

acetylcholinesterase not being produced

In the knee joint, the medial and lateral menisci

act as cushions between the articulating surfaces.

The most important factor in decreasing the intracellular concentration of calcium ion after contraction is

active transport of calcium into the sarcoplasmic reticulum.

Creatine phosphate

acts as an energy reserve in muscle tissue.

When a skeletal muscle fiber is at rest, its ATP demands are met by __________.

aerobic metabolism of fatty acids

A resting muscle generates most of its ATP by

aerobic metabolism of fatty acids.

The fibrocartilage outer layer of the intervertebral disc is called the

annulus fibrosus.

Within an intervertebral disc, which structure provides the tough outer layer of fibrocartilage and which structure provides the soft inner core for resiliency and shock absorption?

anulus fibrosus; nucleus pulposus

What structure covers the bony surfaces of a synovial joint to prevent the surfaces from touching?

articular cartilage

Which of the following athletes are at greatest risk of developing a rotator cuff injury?

baseball pitchers

The surface of articular cartilage is

both slick and smooth.

Small pockets of synovial fluid that reduce friction and act as a shock absorber where ligaments and tendons rub against other tissues are called

bursae.

Triads in skeletal muscle fibers function in __________.

calcium ion release

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

calcium ions

Interactions between the thick and thin filaments are prevented by tropomyosin. To make the active sites accessible, __________ ions must bind to __________.

calcium, troponin

Smooth muscle contracts when calcium binds to __________ and activates __________.

calmodulin; myosin light chain kinase

Structurally, the pubic symphysis is classified as a ________ articulation.

cartilaginous

A muscle producing its maximum tension for a prolonged period is in __________.

complete tetanus

The ligaments that limit the anterior-posterior movement of the tibia and maintain the alignment of the femoral and tibial condyles are the ________ ligaments.

cruciate

Fatigued muscles signify __________.

decreased pH

A freely movable joint is a(n)

diarthrosis.

A synovial joint is an example of a(n)

diarthrosis.

What is the function of the structure indicated by the arrows?

distribute action potentials throughout the interior of the skeletal muscle cell

Lifting a stone with the tip of foot is

dorsiflexion.

Muscle fibers are directly surrounded by which thin layer of connective tissue?

endomysium

The capillaries that wrap around each muscle fiber are located within the __________.

endomysium

Nerves and blood vessels that service a muscle fiber are located in the connective tissues of its

endomysium.

The origin of the frontalis muscle is the

epicranial aponeurosis.

The thick, flat sheet of tendon deep to the scalp is called the

epicranial aponeurosis.

The dense layer of connective tissue that surrounds an entire skeletal muscle is the

epimysium.

A twisting motion of the foot that turns the sole of the foot outward is known as

eversion.

Synaptic vesicles contain neurotransmitters that are released by ________ when the action potential arrives.

exocytosis

The stylohyoid is innervated by which nerve?

facial

Muscles that move the eyeball have ________ fibers.

fast

The structures that assist the bursae in reducing friction between the patella and other tissues are the

fat pads

Usually found outside the capsule, ________ protect the articular cartilages and act as packing material for the joint.

fat pads

The movements known as dorsiflexion and plantar flexion involve moving the

foot.

The glenoid fossa is rimmed by the fibrocartilaginous

glenoid labrum.

Dense fibrous connective tissue is to a suture as a periodontal ligament is to a(n)

gomphosis.

The synarthrosis that binds the teeth to the bony sockets is a

gomphosis.

Which of the following allows muscles to return to their original shape during relaxation?

gravity, opposing muscle contractions, and elastic forces

A fascicle is a

group of muscle fibers that are encased in the perimysium

Cardiac muscles cells have a sarcolemma that is more permeable to calcium, which causes them to __________.

have contractions that last longer than skeletal muscle fibers

Muscles including the term capitis would be found within or attached to the

head

What is the function of the structure indicated by the arrow?

houses the genetic material (DNA) of the cell

What can the nervous system do to increase muscle tension?

increase stimulation frequency recruit larger motor units increase the number of active motor units

Which of the following is not a function of synovial fluid?

increases osmotic pressure within joint

A weight-lifter strains to lift a heavy weight and there is no movement of the person's arms holding on to the weight. This type of contraction is called a(n) ________ contraction.

isometric

The type of contraction where the tension exceeds the load is called

isotonic concentric contraction.

The type of contraction where the tension is less than the load is called The type of contraction where the tension is less than the load is called

isotonic eccentric contraction.

The three functions of synovial fluid are nutrient distribution, shock absorption, and

lubrication.

What is the function of the structure indicated by the arrow?

making of energy (ATP); "power house" of the cell

The ________ muscle is the strongest jaw muscle.

masseter

The sternocleidomastoid inserts on the

mastoid process of the temporal bone

The most common athletic knee injury produces damage to the

medial meniscus.

Bacteria that cause tetanus release a neurotoxin. Which of the following components of the neuromuscular junction (NMJ) does this neurotoxin affect directly?

motor neurons

Interactions between actin and myosin filaments of the sarcomere are responsible for

muscle contraction.

During the recovery period following exercise, all of the following are true except

muscle fibers are unable to contract.

In an isotonic contraction,

muscle tension exceeds the load and the muscle lifts the load.

In which of the following would the motor units have the fewest muscle fibers?

muscles that control the eyes

The gelatinous core of an intervertebral disc is called the

nucleus pulposus.

To pinch with a thumb and finger involves a movement called

opposition.

The "kissing muscle" that purses the lips is the

orbicularis oris.

During anaerobic glycolysis,

oxygen is not consumed. carbohydrate is metabolized. pyruvic acid is produced. ATP is produced.

The ligament that provides support to the front of the knee joint is the ________ ligament.

patellar

Which muscle is named for either shape or size?

pectoralis major deltoid latissimus dorsi vastus lateralis All of the above are named for shape or size.

The atlantoaxial joint is an example of a ________ joint.

pivot

Which foot movement enables the ballerina to stand on her toes?

plantar flexion

The back of the knee joint is reinforced by ________ ligaments.

popliteal

The iliac crest is the origin of the

quadratus lumborum.

The increase in muscle tension that is produced by increasing the number of active motor units is called

recruitment.

Muscles with fibers that run parallel to the long axis of the body are called

rectus

Which of the following best describes the term sarcomere?

repeating unit of striated myofibrils

After death, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as

rigor mortis.

The coxal bones articulate with the sacrum at the ________ joint.

sacroiliac

In response to an action potential along the transverse tubules, the __________ release(s) calcium ions into the sarcoplasm.

sarcoplasmic reticulum

The joint that permits the greatest range of mobility of any joint in the body is the ________ joint.

shoulder

Which of the following joints is an example of a ball-and-socket joint?

shoulder

The type of muscle fiber that is most resistant to fatigue is the ________ fiber.

slow

What type of muscle fibers has the longest endurance?

slow

Which skeletal muscle fiber typeslow or fastcontains more mitochondria?

slow

What is the function of the structure indicated by the arrow?

storage of calcium

Factors that increase the stability of the hip joint include

supporting ligaments. strong muscular padding. almost complete bony socket. tough capsule.

Which of the following is not a type of synovial joint?

symphysis

An immovable joint is a(n)

synarthrosis

A suture is an example of a(n)

synarthrosis.

Joints can be classified structurally as

synovial. fibrous. bony. cartilaginous.

At each end of the muscle, the collagen fibers of the epimysium, perimysium, and endomysium, come together to form a

tendon

Tom, a trumpet player, asks you which muscles he should develop in order to be a better trumpeter. What would you tell him?

the buccinator and orbicularis oris

Complete dislocation of the knee is rare because

the knee contains seven major ligaments

In rigor mortis

the myosin heads are attached to actin. calcium ions keep binding to troponin. sustained contractions occur. ATP is depleted.

The muscle action potential penetrates deep into a fiber along the __________.

transverse tubules

The action potential is conducted into a skeletal muscle fiber by

transverse tubules.

Muscles with fibers that run perpendicular to the long axis of the body are called

transversus.

At rest, active sites on the actin are blocked by

tropomyosin molecules.

When calcium ion binds to troponin

tropomyosin rolls away from the active site

A single contraction-relaxation cycle in a muscle fiber produces a(n)

twitch

Increased muscle fiber endurance can be produced by __________

type of activity preformed

The muscle that raises the corners of the mouth as when smiling is the ________ muscle.

zygomaticus major