Anatomy & Physiology (Exam 2)

The right hand and wrist of an adult has _____________ bones.

27

During muscle contraction, a single myosin head consumes ATP at a rate of about:

5 ATP per second.

Which of the following sutures articulates with the most bones?

Lambdoid suture

Synovial fluid

decreases friction between bones.

The axis is the only vertebra with a

dens (odontoid process).

The membrane ____________ , or becomes less negative.

depolarizes

Tennis elbow is a common term describing injury to which of the following?

extensor carpi radialis longus

The brachium contains the ________________, whereas the antebrachium contains the ________________.

humerus; radius and ulna

The ____________ muscle is the convergence of the iliacus muscle and the psoas major muscle.

iliopsoas

The ____________ helps to provide an attachment point for the tensor fasciae latae muscle and the ____________ muscle.

iliotibial tract; gluteus maximus

If one nerve stimulus arrives at a muscle fiber so soon that the fiber has only partially relaxed from the previous twitch, the most likely result will be

incomplete tetanus.

When all nerve fibers are stimulated, an increase in stimulus strength will produce no ____________ in muscle tension.

increase

The ligament at the head of the femur is the:

ligamentum teres.

Acetylcholine receptors function as ____________ .

ligand-gated ion channels.

The synovial membrane

lines the joint everywhere except over the articular cartilage.

Athletes who train at high altitudes increase their red blood cell count and thus increase their oxygen supply during exercise. Increased oxygen supply results in

longer aerobic respiration.

The ____________ muscle laterally rotates the extended thigh and is innervated by spinal nerves.

piriformis

A cell membrane is ____________ when there is a higher concentration of cations on one side, and a higher concentration of ____________ on the other.

polarized; anions

A skydiver's parachute fails to deploy. After some struggle, his reserve chute deploys in time to save his life. However, his landing is harder than normal and he feels his knee slightly hyperextend. He shakes it off and goes about his normal routine. Later that day he begins experiencing knee pain. Two days later he notices that his knee "pops" when he crouches and soon discovers he has dislocated his femur on the knee. What muscle was likely injured initially?

popliteus

The ___ can be easily palpated between the clavicles.

suprasternal notch

Most of the bones of the skull are connected by immovable joints called

sutures.

Which of the following joints is most movable?

synovial

During fracture healing, cartilage is deposited in granulation tissue to form which of the following?

A soft callus

Articular cartilage:

covers the ends of bones in synovial joints.

The speediest way for muscle cells to make ATP is by breaking down ____________ , which occurs in the midst of the sliding filaments.

creatine phosphate

Which of the following statements is true about the functions of cardiac muscle?

-- Cardiac muscle almost always utilizes aerobic respiration to obtain energy. -- Cardiac muscle secures some if its calcium ions from the sarcoplasmic reticulum. -- Autorhythmic cells allow the myocytes to contract consistently and regularly, efficiently pumping blood from the chambers.

Which of the following is/are a functional requirement of cardiac muscle tissue?

-- Cardiac muscle fibers must be able to contract without nervous stimulation. -- Cardiac muscle must be independent of conscious control. -- Cardiac muscles contract in unison.

Which of the following will result in an increase in muscle twitch strength?

-- Increase in stimulus frequency -- Increase in muscle temperature -- Increase in pre-twitch muscle length approaching optimal resting length

Which of the following is a functional requirement of cardiac muscle tissue? -- Muscle fibers must contract without nervous stimulation. -- Muscles must be voluntary as well as involuntary. -- Cardiac muscle fatigues easily. -- Cardiac muscle must be independent of conscious control. -- Cardiac muscles contract in unison.

-- Muscle fibers must contract without nervous stimulation. -- Cardiac muscle must be independent of conscious control. -- Cardiac muscles contract in unison.

Which of the following is a characteristic of skeletal muscle? Check all that apply.

-- Overlapping thin and thick filaments -- Striations -- Overlapping myosin and actin proteins -- Excitability

There are bones closely associated with the skull, that are not considered part of it. Select the accurate statements regarding these bones:

-- The auditory ossicles are named the malleus, incus, and stapes. -- Forensic pathologists look for a fractured hyoid as evidence of strangulation. -- The hyoid is one of the few bones that does not articulate with any other. -- There are (7), three auditory ossicles in each middle-ear cavity and the hyoid bone beneath the chin.

Arrange the following list of biochemical events in the correct sequence. (1) An action potential is conducted deep into the muscle fiber by the T tubule. (2) Calcium ions bind to troponin. (3) The membranes of the sarcoplasmic reticulum become more permeable to calcium ions. (4) Calcium ions diffuse into the sarcoplasm around the myofibril. (5) The troponin-tropomyosin complex moves exposing active sites.

1, 3, 4, 2, 5

Based on the size, shape, and ratio of muscle fibers to motor neuron (motor unit), rank the following muscles in order of strongest to weakest, starting with #1 being the strongest.

1. Quadriceps femoris 2. Gastrocnemius 3. Brachialis 4. Orbicularis oculi 5. Lateral rectus

Which of the following would directly affect osseous tissue?

A Vitamin C deficiency

What is a retinaculum?

A band of connective tissue that covers and stabilizes a group of tendons

Which of the following movements is possible at the hip or coxal joint?

All of these are possible. (circumduction, flexion, adduction, rotation)

Within compact bone, a central canal is found at the center of which structure?

An osteon

What is the primary action of the masseter?

Elevation of the mandible

____________ is the process, in which action potentials in the nerve fiber lead to action potentials in the muscle fiber.

Excitation

Where does bone formation occur during endochondral ossification?

Hyaline cartilage model

Which of the following best describes the role of Ca2+ in muscle contraction?

It binds to troponin, moving tropomyosin, so that myosin heads can bind to actin.

Which of the following is true regarding the levator scapulae?

It flexes the neck if the scapula is fixed.

Which of the following best describes the insertion of the extensor digitorum?

It indirectly inserts on all digits of the hand except the thumb.

Excitation-contraction coupling refers to the events that link the action potentials on the sarcolemma to activation of the ____________ . It begins with the arrival of the ____________ at the neuromuscular junction.

Myofilaments; action potential

In an adult, which of the following is a bone that does not contain red bone marrow?

Radius

Which of the following best describes the resting membrane potential (RMP)?

The intracellular environment is negatively charged.

_____________ do(does) not belong to the pectoral girdle.

The sacroiliac joint

Choose the INCORRECT statement regarding the development of the skull from infancy through childhood.

The skull reaches about three-quarters its adult size by age 1.

____________ moves back into position, blocking active sites, which prevents more contraction.

Tropomyosin

True or False: A sacral fracture affecting the S3 and S4 nerve roots would result in a person having difficulty with evacuation of the bowels.

True, the coccygeus is innervated by the 3rd and 4th sacral nerves and assists the levator ani.

True or False: Injury to the deep fibular nerve would cause inability to extend ones toes.

True, the deep fibular nerve innervates the anterior compartment of the leg.

Because skeletal muscle is under the conscious control it is said to be what?

Voluntary

Which of the following movements does not occur at the knee joint?

abduction

Osseous tissue matrix is composed of __________.

calcium phosphate

Most of the ATP generated by a muscle cell comes from ____________ , which uses either glucose or ____________ to produce ATP. A muscle-specific molecule called ____________ helps provide oxygen for this process.

cellular respiration; fatty acids; myoglobin

The ____________ muscle acts to open a fist and spread out the fingers.

extensor digitorum

What is the most commonly dislocated joint in the body?

glenohumeral joint

The ____________ attaches on the greater trochanter and assists in maintaining pelvic balance while walking.

gluteus medius

Spines of the _____ form a part of the pelvic outlet.

ischium

The center cavity of the diaphysis of a long bone is called the __________.

marrow cavity

Bone protrudes through the skin in a fracture called __________.

open

After taking their wedding vows, a bride and groom often ceremonially use which of the following muscles before walking away from the altar?

orbicularis oris

___________ are not facial bones.

parietal bones

Sodium ion channels close, but ____________ channels remain open, and loss of that ion ____________ the membrane.

potassium ion ; repolarizes

There is then a rapid fluctuation in membrane voltage at the motor end plate, called the end-plate ____________ .

potential

Somatic efferents release neurotransmitters into the synaptic cleft, which elicits a ____________ from the muscle tissue.

response

In order to provide a stable base of force transmission into the axial skeleton, the scapula must be stabilized by the action of the ____________ major, pectoralis minor, and serratus anterior muscles, which act as fixators.

rhomboid

Costal cartilages connect

ribs with the sternum.

One motor axon goes to ____________ .

several muscle fibers.

Fontanels are ____________ in an infant.

spaces between the unfused cranial bones

The skeletal muscles are innervated by __________.

spinal nerves and cranial nerves

Male and female pelves differ in the following features except

the female sacrum is longer.

The manubrium belongs to

the sternum.

These are bones associated with the skull but not considered part of it except

the vomer.

Which statement best describes the goal of medications used to treat myasthenia gravis?

to inhibit the function of cholinesterase

The purpose of varicosities in motor nerve fibers in muscle physiology is

to release neurotransmitter onto smooth muscle cells.

Rib 7 is a

true rib

The biceps femoris has ____________ different heads.

two

Which fibers are primarily responsible for producing lactic acid?

type IIB fast glycolytic fibers

In a muscle fiber the ____________ is adjacent to the terminal cisternae so the action potential can stimulate calcium ion channels.

T tubule

Voltage sensitive proteins respond to the action potential that spreads down the ____________ .

T tubule

In the ____________ , action potentials open voltage-gated ion channels, whose physical connections cause the release of calcium ions from the terminal cisterns of the sarcoplasmic reticulum into the cytosol.

T tubules

Which of the following is not a component of the skeletal system?

Tendons

Which of the following individuals would have more mitochondria in her skeletal muscle?

a 22-year-old football player

The amount of ATP that normally exists in a muscle cell lasts for ____________ during strenuous exercise.

a few seconds

An injury that results in complete functional loss of the ulnar nerve will affect which of the following muscles?

abductor digiti minimi

Arteriosclerosis is one example of ectopic ossification, which means __________.

abnormal calcification of a tissue

What is(are) the innervation(s) of the palatoglossus?

accessory and vagal nerves

Relaxation begins when nerve signals stop stimulating the synaptic knob and ____________ release ceases.

acetylcholine

The ions stimulate the release of ____________ into the synaptic cleft.

acetylcholine

Areas of the sarcolemma near the motor plate have gates that open, moving ions, which causes the ____________ potential that excites the muscle fiber.

action

The process just described is called a(n) ____________ .

action potential.

The head extends toward the exposed ____________ site on the thin filament.

active

The pump mechanism that maintains the resting membrane potential is an example of ____________ .

active transport.

The ____________ muscle contributes to the action of returning an abducted thigh to anatomical position.

adductor magnus

When the torque (force) produced by the ____________ exceeds that of the antagonist, knee extension occurs.

agonist

Muscle contraction can be studied using isolated, single muscle fibers. As opposed to a whole muscle, a single muscle fiber shows ____________ contraction.

all-or-none

If a thyroid tumor secreted an excessive amount of calcitonin, we would expect ___________.

an elevated level of osteoblast activity

The ____________ muscles, such as the pectoralis major, anterior deltoid, and bicep brachii, control deceleration, gravitational forces, and stabilize the opposite motion of the joint.

antagonist

The ______________ does not belong to the femur.

anterior crest

In a herniated ("ruptured" or "slipped") disc, the ring of fibrocartilage called the ___________ cracks and the _____________ oozes out.

anulus fibrosus; nucleus pulposus

An articulation, or joint, is defined as ___________.

any point where two bones meet.

A male sustains a crushing injury to his foot. After weeks of care, he begins to notice that he cannot bend the little toe on his right foot. A logical diagnosis would be

atrophy of the flexor digiti minimi.

Skeletal muscle is ____________ the skeleton. A layer of connective tissue covers the skeletal muscle. This tissue contributes to the ____________ , which attaches the muscle to the bone.

attached to; tendon,

Myasthenia gravis is a/an ____________ disease characterized by muscle weakness in the eyelids, face, neck, and extremities.

autoimmune

An Olympic sprinter readies for a race. After the sound of the starting gun, he propels himself forward from the starting block and immediately grimaces in pain, grabbing for the back of his thigh. Within 48 hours he begins noticing extensive bruising on the back of his thigh extending into the back of the knee. He now has difficulty rising from a seated position and flexing his knee. Bending at the waist generates more pain. Which muscle is likely injured?

biceps femoris

The hamstring group consists of ____________ , semimembranosus, and semitendinosus muscles.

biceps femoris,

Skeletal muscle contraction allows the body to move, remain upright, and produces heat as ATP is ____________ .

broken down

A heavyset middle-aged insurance salesman who doesn't exercise often accepts his friend's invitation to a pickup basketball game. When attempting a jump shot, he falls to the ground in pain, grasping at the calf of his leg. There is an enormous bulge in his leg immediately below the knee, and he is unable to plantar flex that foot. Most likely he has injured his ___ and the bulge is ___.

calcaneal tendon; his triceps surae

Active transport pumps in the SR move ____________ ions back into the cisternae.

calcium

The process begins with a nerve signal stimulating a voltage-gated ____________ ion channel to open, allowing the ions to enter the axon terminal.

calcium

Voltage-gated ____________ in the ____________ open and release ions into the sarcoplasm.

calcium ion channels; terminal cisterns

Stimulated by ____________ , acetylcholine is released into the synaptic cleft via ____________ .

calcium ions; exocytosis

Muscle contractions are initiated by the binding of __________ to __________.

calcium ions; troponin

Mineralization is a process that extracts __________ and __________ from the blood plasma and deposits it into bone.

calcium; phosphate

Bone elongation is a result of __________.

cartilage growth

Creatine kinase

catalyzes the transfer of phosphate from CP to ADP.

The spinous process has a bifid tip in most _______________ vertebrae.

cervical

If the __________ component of bone is not in adequate amounts, the flexibility of bone will be compromised.

collagen

A fracture in which the bone is broken into three or more pieces is called a __________ fracture.

comminuted

The knee joint is an example of a _____ joint.

complex ellipsoid

The biceps brachii and brachialis begin to flex the elbow with greater force than the elbow extensors resulting in a(n) ____________ contraction.

concentric

Acting as the agonist, the quadriceps contracts ____________ producing knee extension.

concentrically

Osseous tissue is a(an) ____________ tissue.

connective

Subthreshold stimuli produce no muscle ____________ .

contraction

The step in which the muscle fiber develops tension and may shorten is called ____________ . It begins after the active site on actin is exposed.

contraction

A drug that interferes with the active transport of calcium ions from the sarcoplasm back into the sarcoplasmic reticulum would result in

contraction with no relaxation.

In comparison to skeletal muscle, smooth muscle

contracts and relaxes more slowly.

A ____________ is formed by the attachment of the myosin head to the thin filament.

cross-bridge

Which one of these muscles helps to open the mouth (depress the mandible)?

digastric

Antagonizing the action is where the hamstrings contract ____________ and resist knee extension.

eccentrically

Collagen is:

elastic.

Increasing the flexion angle of the elbow, the elbow extensors exhibit ____________ while the flexors eccentrically contract.

elasticity

When an ion channel opens in a sarcolemma, ions flow across the membrane altering the potential. These cells are said to be ____________ .

electrically excitable

The connective tissue that surrounds each muscle fiber is called the ____________ .

endomysium

The thin layer of slightly denser spongy bone that separates an adult's epiphysis from the diaphysis is called the __________.

epiphyseal line

While sitting at your desk, you drop your pencil onto the floor. You bend over to pick up the pencil. In order to straighten up and continue your exam you must use which of the following muscles?

erector spinae

Osteoporosis is most common in elderly women because of the lack of ___________, which would otherwise inhibit ____________.

estrogen; osteoclast activity

There are two of each of the following bones except for the unpaired

ethmoid bone(s).

When you walk up the stairs your hip and knee joints _____________ to lift your body weight.

extend

Nearing 60 degrees of elbow flexion, the antagonistic triceps brachii continues to demonstrate the characteristic of ____________ .

extensibility.

The final position of someone rising from a chair to a standing position is one of full knee ____________ .

extension.

The lateral epicondyle of the humerus is one of the proximal skeletal attachment sites of the ____________ muscle.

extensor carpi ulnaris

The ____________ muscle has a skeletal attachment on the distal phalanx of the first digit.

extensor hallucis longus

The ____________ muscle converts a fist into a "thumbs-up" position.

extensor pollicus brevis

The ____________ are the broad ligamentous sheets that contain the tendons of the anterior compartment muscles.

extensor retinacula

Some people suffer involuntary urination because of incompetence of what muscle?

external urethral sphincter

Michael Jordan was arguably the best player in professional basketball history. Scientifically one would expect him to have highly developed

fast-twitch fibers.

The acetabulum articulates with the

femur.

There are three ways that muscles can obtain new ATP. Two methods, ____________ and creatine phosphate breakdown, are anaerobic and are therefore available even when oxygen supplies are low during vigorous activity.

fermentation

Millions of Americans suffer from ____________ , a muscle and ligament disorder that causes chronic pain and fatigue. The cause of this disease is still unknown but may be due to underlying ____________ .

fibromyalgia; infection

Pain in a synovial joint such as the hip can occur because of irritation of the nerves in the

fibrous capsule of the joint.

The occurrence of the co-contraction of the hip adductors and abductors serve as ____________ in order to prevent lateral shifts in the femur.

fixators

During the upward phase of a pull-up (with narrow grip and a supinated grip), the glenohumeral joint is moving from a position of ____________ to a position of extension.

flexion

Rising from a chair, the knee starts in a position of ____________ .

flexion

A butcher who cuts the distal portion of his fingers may cut the

flexor digitorum profundus tendon.

Carpal tunnel pressure is sometimes relieved by surgically excising part or all of which structure?

flexor retinaculum

Which of the following would be caused by contraction of smooth muscle?

goose bumps

The training regimen of a competitive weight lifter is designed partly to

increase the average number of myofibrils per muscle fiber.

Summation is ____________ muscle contraction.

increased

A child ingested an organophosphate poison used to kill insects. Soon the child's muscles began spastic contractions. Predict what occurred at the synaptic cleft.

increased accumulation of acetylcholine in the synapse

Which of the following is NOT a known effect of illegal use of anabolic steroids in large dosages?

increased cardiovascular fitness

Which of the following changes have the potential to dramatically affect the potential difference across the plasma membrane?

increased permeability of the membrane to sodium ions and increased intracellular concentration of potassium ions

Release of acetylcholine at a neuromuscular junction

increases permeability of the sarcolemma to Na+.

The aponeurosis of the external oblique forms the ________ at its inferior margin.

inguinal ligament

intramembranous ossification vs endochondral ossification

intramembranous: parietal, maxilla

The joint capsule

is a double layer of tissue that encloses a joint.

The fibrous capsule

is a layer of tissue that is continuous with the periosteum.

Synovial fluid:

is a thin lubricating film covering the surface of a joint.

The knee flexors all have skeletal attachments on the ____________ .

ischial tuberosity

Pausing at the top while a drink is taken, ____________ contractions are seen in the elbow flexors.

isometric

Identify the correct statement(s) regarding the development of the skull from infancy through childhood.

-- The anterior fontanel can still be palpated 18 to 24 months after birth. -- The frontal bone and mandible are separate right and left bones at birth. -- The skull grows more rapidly than the rest of the skeleton during childhood.

Identify the correct statement(s) regarding cranial bones. -- The maxillae are the largest cranial bones. -- The cranium consists of two major parts: the calvaria and the base. -- The cranium is composed of eight cranial bones. -- The first and second choices are correct. -- The second and third choices are correct.

-- The second and third choices are correct.

Consider the number of bones found in each region of the adult body, including both the left and right sides of the body as well as the phalanges on the hands and feet.

-- There are 22 skull bones. -- There are four bones in the pectoral girdle. -- There are 56 phalanges.

Which of the following is a true statement regarding muscular strength and conditioning? -- Weight lifting does not increase the number of muscle fibers in a particular muscle exercised. -- Swimming will increase the number of muscle fibers in a particular muscle exercised. -- Blood capillary density will increase in slow-twitch fibers in response to training for a marathon. -- Long-term resistance training will increase the number of myofibrils in a particular muscle exercised. -- As muscle fibers become too large, mitosis causes them to divide into two.

-- Weight lifting does not increase the number of muscle fibers in a particular muscle exercised. -- Blood capillary density will increase in slow-twitch fibers in response to training for a marathon. -- -- Long-term resistance training will increase the number of myofibrils in a particular muscle exercised.

Consider the following four phrases and select the one that does not belong with the others. -- anaerobic metabolism -- fuels runner in a marathon -- fast twitch fibers -- muscle fibers split ATP rapidly -- lactic acid production

-- fuels runner in a marathon

The contraction strength of smooth muscle is relatively independent of its resting length partly because:

it does not have sarcomeres.

These are all features found in a typical thoracic vertebra except

it has a pair of transverse foramina.

In lifting a heavy weight from the floor, one should use the power of the ___ in order to avoid muscle strain in the lower back.

knee and hip extensors

The medial meniscus is in the

knee.

During fermentation, glucose is broken down into ____________ , which can result in cramping and fatigue.

lactate

The spaces found within the concentric lamellae are called __________, and they contain __________.

lacunae; osteocytes

The contraction of a single muscle fiber can be divided into three stages: the ____________ period (time between stimulation and initiation of contraction), the ____________ period (when the muscle shortens), and the ____________ period (when the muscle returns to its former length).

latent; contraction ; relaxation

The ____________ of the tibia is a skeletal attachment site of the tibialis anterior muscle.

lateral condyle

The ____________ would be considered the prime mover due to its ability to produce the majority of the torque.

latissimus dorsi

Muscle cancer can occur in smooth and skeletal muscles. For instance, a ____________ occurs in the smooth muscle of the uterine wall, while ____________ are a rare form of cancer that sometimes originate in skeletal muscle.

leiomyoma; rhabdomyosarcomas

Which of the following muscles of facial expression is not innervated by the facial nerve?

levator palpebrae superioris

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. This is because the soleus muscles

make more use of aerobic respiration.

Tetanus is ____________ sustained muscle contraction.

maximal

Wolff's law of bone explains the effect of __________.

mechanical stress on bone remodeling

You cannot palpate the ________________ on a living person.

medial surface of the fibula

The difference in charge created by the ECF ions and the ICF ions is called the ____________ .

membrane potential.

The thick fibrocartilage disks found in the knee joint are called

menisci.

Membrane potential is measured in ____________ .

millivolts.

Acetylcholine diffuses across the synaptic cleft before binding to its receptor, which is located on the ____________ .

motor end plate.

If an appropriate force is applied, the ____________ returns to its resting length.

muscle fiber

Hypocalcemia can cause __________.

muscle spasms

When the strength of a stimulus is above a threshold level, the muscle contracts and then relaxes. This action is called a ____________ and lasts only a fraction of a second.

muscle twitch

The ____________ are a group of ____________ diseases that affect the muscles. These disorders vary considerably in their severity.

muscular dystrophies; genetic

Each myofibril is made of up of several ____________ .

myofilaments

Which of the following is very important for muscle to continue contraction during anaerobic respiration?

myokinase

On the thin filament, active sites are open for the binding of ____________ heads, which allows the contraction to begin.

myosin

The ____________ bind to the active sites and form ____________ between the thick and thin filaments.

myosin heads; cross-bridges

Within the ____________ , a synaptic cleft lies between each axon terminal and muscle fiber. Nerve impulses cause synaptic vesicles to discharge ____________ .

neuromuscular junction; acetylcholine (ACh).

Exposure to Clostridium tetani causes continuous release of acetylcholine. What effect does this have on smooth muscle?

no effect

Blood Ca2+ deficiency stimulates __________ secretion, which leads to __________.

parathyroid hormone; increased osteoclast activity

A skeletal muscle generates the greatest tension when it is:

partially stretched before being stimulated.

The patella is connected to the tibia via the ____________ .

patellar ligament

A break in a bone that is already weakened by some other disease is called a(n) __________ fracture.

pathologic

Which muscle acting on the arm assists in deep inspiration?

pectoralis major

A newborn passes through the __________________ during birth.

pelvic outlet

A skateboarder falls and lands directly on his buttocks and lower back. He does not feel too much pain and so he continues skating. After a couple of days he begins experiencing right hip pain and notices his right foot and leg are rotated to the right. A doctor diagnoses muscle spasm. Which of the following muscles is most likely causing the leg and foot rotation?

piriformis

Slight rotation between the femur and tibia is possible due to the action of the ____________ muscle.

popliteus

The myosin head pushes forward, moving the thin filament toward the M line. This is called the ____________ stroke.

power

Drugs called calcium channel blockers may be used to lower blood pressure by causing arteries to vasodilate. These drugs:

prevent calcium from entering smooth muscle, thus allowing the muscle to relax.

Moving the forearm from anatomical position to the prone position is called pronation and is achieved by contracting the ____________ muscle.

pronator quadratus

The function of a bursa is to

provide a fluid-filled cushion that reduces friction.

Articular cartilage

provides a smooth surface where bones meet.

The pivoting motion that results in supination of the forearm takes place at the ____________ joint.

proximal radioulnar

The ____________ is a group of muscles that extend the knee and all insert on the patella.

quadriceps femoris

Acetylcholine dissociates from its ____________ and is broken down enzymatically.

receptor

Once more ATP binds, myosin will release from the actin and hydrolyze another ATP. This is called the ____________ stroke.

recovery

As you are lifting a box, someone places extra weight on top of it. For your muscle to continue contracting and lifting the box, the muscle must

recruit more muscle fibers.

The process of bringing more motor units into use during a muscle contraction is called:

recruitment.

The ____________ muscle is the only muscle of the quadriceps femoris group that flexes the hip.

rectus femoris

The ____________ and the serratus anterior muscles both attach on the medial border of the scapula.

rhomboid major

The result of blood calcium and phosphate levels being too low for normal deposition is a softness of the bones called __________ in children and __________ in adults.

rickets; osteomalacia

The muscles that hold the humeral head within the glenoid cavity are collectively called the

rotator cuff.

A(n) __________would not involve damage to the structures that comprise the skeletal system.

ruptured calcaneal (Achilles) tendon

A clinician induces contraction of the gastrocnemius and soleus and notices that the foot does not plantar flex as expected. Which of the following would be a logical diagnosis?

ruptured calcaneal tendon

The specific name for a muscle fiber's plasma membrane is the ____________ .

sarcolemma

This neurotransmitter diffuses across the cleft and binds to receptors in the ____________ , which generates electrical signals that spread across it and down the ____________ .

sarcolemma; T tubules.

Muscle cancer belongs to a group of cancers called soft tissue ____________ , which may also occur in bone, adipose, and cartilage.

sarcomas

Next, a wave of action potentials spreads from the end plate in all directions, reaching the T tubules, which carry the excitation wave into the ____________ .

sarcoplasm.

Terminal cisternae are a structural feature of the organelle called the ____________ .

sarcoplasmic reticulum

This stimulates the release of calcium ions from the ____________ , which leads to sarcomere contraction.

sarcoplasmic reticulum

An action potential causes calcium ions to diffuse from the ________ into the ________.

sarcoplasmic reticulum; sarcoplasm

The ____________ muscle's action is to aid in both hip and knee flexion.

sartorius

Cardiac muscle has very little capacity for regeneration because it lacks

satellite cells.

The acromion is a feature of the

scapula.

The glenoid cavity of the _______________ articulates with the head of the _____________.

scapula; humerus

The most common deformity is an abnormal lateral curvature called

scoliosis.

The _________ houses the pituitary gland (hypophysis) and is found in the ____________.

sella turcica; sphenoid bone

The ____________ muscle is important in thrusting movements of the arm, much like a boxer's jab punch.

serratus anterior

The subscapular and subacromial bursa are associated with the _________ joint.

shoulder

A tennis player goes to the doctor and is told he has a torn rotator cuff. He has injured his

shoulder.

The glenoid labrum is part of the _____ joint while the acetabular labrum is part of the _____ joint.

shoulder; hip

Which muscle(s) can contract without the need for nervous stimulation?

smooth and cardiac muscle

In response to acetylcholine binding, ____________ move into the muscle fiber causing the membrane potential to rise.

sodium ions

Ion channels open in the plasma membrane and ____________ diffuse into the ____________ .

sodium ions ; ICF

Spicules and trabeculae are found in __________.

spongy bone

The ______________ suture separates the temporal bone from the parietal bone.

squamous

Which of the following correctly states the origin and insertion of the sternocleidomastoid?

sternal manubrium and MEDIAL ONE-THIRD of clavicle; mastoid process and lateral half of superior nuchal line

In a whiplash injury, the neck undergoes forced hyperextension then hyperflexion, injuring multiple muscles in the neck. Which of the following muscles would be injured during the hyperextension phase of the injury?

sternocleidomastoid

The _____________ belongs to the thoracic cage, whereas the _____________ belongs to the pectoral girdle.

sternum; clavicle

A muscle cell is ____________ by a neurotransmitter from a motor neuron.

stimulated

Repeated muscle ____________ results in summation and tetanus. This creates greater force because the muscle ____________ between stimuli.

stimulation; cannot relax

Skeletal muscle has ____________ cells with ____________ nuclei. It functions in ____________ movement of body.

striated; multiple; voluntary

The more motor units excited, the ____________ the contraction.

stronger

The lesser tubercle of the humerus is the distal skeletal attachment site for the ____________ muscle.

subscapularis

When multiple motor units are excited, it is termed motor unit ____________ .

summation

When the muscle is not allowed to relax completely between stimuli, ____________ occurs. The contractions gradually increase in intensity.

summation

The ____________ angle of the scapulae is an attachment of the levator scapulae muscle.

superior

Returning the forearm to anatomical position from the prone position is called supination and is achieved by contracting the ____________ and the biceps brachii muscles.

supinator

Downward slippage of the humeral head when relaxed may indicate an injury to the ____________ muscle.

supraspinatus

What are the four rotator cuff muscles?

supraspinatus, infraspinatus, teres minor, subscapularis

The supraspinatus muscle lies in the ____________ of the scapula.

supraspinous fossa

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

synaptic knob

Sinuses are not found in the

temporal bone.

Smaller muscle groups with a similar functional ability might include the ____________ major which acts as synergist in producing the same action as the agonist.

teres

The absence or inhibition of acetylcholinesterase at a synapse would lead to which of the following?

tetanus

When maximal sustained contraction is reached, ____________ is achieved. This stage will continue until ____________ occurs, and the muscle relaxes even though stimulation continues.

tetanus; fatigue

A soft callus forms during ___________.

the healing of a fracture

All of these contribute to the wall of the orbit except:

the nasal bone

Which intervertebral disc is largest?

the one between L4 and L5

Which of the following systems would provide energy for a racquetball player?

the phosphagen system

After childbirth a woman begins experiencing tremendous pain in her groin, making it difficult for her to walk. She has difficulty walking due to the pain. An X-ray shows a fracture extending from her symphysis pubis to the inferior ramus of the pubis. As a result of the fracture, which group of muscles might be impaired?

thigh adductors

When stimuli reach or exceed ____________ , they excite more motor units.

threshold

When the membrane potential reaches ____________ an action potential spreads across the sarcolemma due to the opening of ____________ .

threshold ; voltage-gated Na⁺ channels

In an adult, a compound fracture of the __________ could lead to a "fat" embolism entering the blood stream.

tibia

Inversion and dorsiflexion of the foot is achieved by contracting the ____________ muscle.

tibialis anterior

Which of the following muscles is not externally visible on the trunk of the body?

transverse abdominal

The ____________ muscle contributes to elevation, depression, rotation, and retraction of the scapula.

trapezius

The muscles that laterally rotate and depress the scapula, as in shrugging and lowering the shoulders, are the

trapezius and serratus anterior.

Calcium will bind to the ____________ of the thin filaments.

troponin

A conformational change in the ____________ occurs, revealing active sites on the ____________ .

troponin-tropomyosin complex; actin filaments.

These ions bind to ____________ , which forms a complex with ____________ .

troponin; tropomyosin.

An action potential reaches the axon terminal causing ____________ to open.

voltage-gated Ca²⁺ channels

These are bones associated with the skull but not considered part of it except:

vomer

Red bone marrow does not contain __________.

yellow bone marrow

Vertebrae are divided into five groups, usually ____________ cervical, ____________ thoracic, _________________ lumbar, ___________ sacral, and ____________ coccygeal.

7; 12; 5; 5; 4

The myosin head must have an ____________ molecule bound to it to initiate the process.

ATP

In people with this disease, antibodies that destroy ____________ impair muscle contraction.

Ach receptors

A reason that muscle twitches become progressively stronger in treppe is

Ca2+ accumulates in the sarcoplasm faster than the sarcoplasmic reticulum can reabsorb it.

What is the action of the orbicularis oris?

Closes and protrudes lips as in kissing

What is the calcium-phosphate salt deposited within bone called?

Hydroxyapatite

Which of the following is an inorganic component of the bone matrix?

Hydroxyapatite

Which of the following statements concerning types of muscle contractions is false?

In isometric contractions, the amount of tension produced by the muscle is constant.

Drag each label into the proper position in order to identify the outcome of each condition on blood calcium.

Increases blood calcium: -- osteoclastic activity, calcitriol Decreases blood calcium: sunBlock, osteoBlast, Northern, calcitoNin

In skeletal muscles, which of the following is true regarding the calcium needed for contraction?

It is stored in the sarcoplasmic reticulum.

Choose the INCORRECT statement regarding the general features of the vertebral column.

The vertebral column consists of a chain of 30 vertebrae with intervertebral discs of fibrocartilage between most of them.

_____________ does not belong to a representative vertebra.

The vertebral head

What is excitation-contraction coupling?

The events that link the action potential of the sarcolemma to the activation of the myofilament contraction

Choose the correct statement(s) regarding the changes that take place in bones as a person ages. -- Adults have fewer bones because many bones fuse through the years. -- At birth there are about 270 bones, but less bones form during childhood. -- The adult pelvis is a single hip bone, which results from the fusion of three childhood bones. -- The fusion of several bones, completed by late adolescence to the mid-20s, brings about the average adult number of 206. -- The first, third, and fourth choices are correct.

The first, third, and fourth choices are correct.

Which of the following is true concerning isotonic eccentric contraction?

The muscle lengthens but tension remains constant.

_______________ is not found as a part of the temporal bone.

The sella turcica

What is the purpose of the triad?

The triad allows for Ca2+ release when a muscle fiber is excited.