A&P fINAL

Straight

E. Right angles

Short

Triangle

D. Rib

F. Wrist

thigh extension.

See pages 363-367 (Table 10.14). The hamstrings are fleshy muscles of the posterior thigh. They cross the hip joint and knee joint. The hamstrings and the gluteus maximus are the primary thigh extensors. The Iliopsoas is the primary thigh flexor. The sartorius is able to flex, abduct, and laterally rotate the thigh.

False

external urethral sphincter.
See pages 344-345 (Table 10.7). The levator ani and the coccygeus form the pelvic floor (or pelvic diaphragm). The deep transverse perineal muscle supports pelvic organs. The external urethral sphincter surrounds the urethra and allows for voluntary control of urination.

Styloglossus

See pages 332-333 (Table 10.2). All of the listed muscles, except for the styloglossus, are involved in chewing/biting movements. The styloglossus is involved in retracting and elevating the tongue.

pectoralis major.

erector spinae muscles.

See pages 336-338 (Table 10.4). The erector spinae muscles are the prime movers of back extension. The head is moved by muscles that originate from the axial skeleton. The major head flexor muscles are the sternocleidomastoid muscles. The scalene muscles elevate the first two ribs and flex and rotate the neck. The pectoralis major muscle is the prime mover of arm flexion.

inhalation.

See pages 340-341 (Table 10.5). The primary function of the deep muscles of the thorax is to promote breathing. The external intercostal muscles are used in inhalation (inspiration) while the internal intercostal muscles have a role in forced expiration (forced exhaling).

Omohyoid muscle

See page 334 (Table 10.3). The suprahyoid muscles (the digastric, stylohyoid, mylohyoid, and geniohyoid muscles) form the floor of the oral cavity. Infrahyoid muscles are strap-like muscles that depress the hyoid bone and larynx during swallowing and speaking. Sternohyoid, sternothyroid, thyrohyoid, and omohyoid muscles are classified as infrahyoid muscles.

inhalation occurs.

Antagonists

2

See page 321. Muscles are sometimes named for the number of origins they have. When biceps, triceps, or quadriceps forms a part of the muscle name, you can assume that the muscle has two, three, or four origins, respectively.

circular

False

See pages 322-323. Muscle power depends more on the total number of muscle fibers than on the degree of shortening upon contraction. Muscles with parallel fascicle arrangement shorten a great deal upon contracting, yet these types of muscles do not tend to be powerful. In contrast, the stocky bipennate and multipennate muscles shorten only a little upon contraction, yet these muscles are powerful.

second-class lever.

Adductor longus

Temporalis

Transverse abdominis

Deltoid

Gluteus maximus

Agonists

Synergists

Antagonists

Epicranius

Orbicularis oculi

Zygomaticus

Depressor labii inferioris

Temporalis

Masseter

Medial pterygoid

Lateral pterygoid

Sternocleidomastoid

Semispinalis capitis, cervicis, and thoracis

Splenius capitis and cervicis

Scalenus

Trapezius

Rhomboids (major and minor)

Levator scapulae

Latissimus dorsi

Deltoid

Subscapularis

Supraspinatus

Biceps brachii

Brachialis

Triceps brachii

Anconeus

Pronator teres

Flexor carpi radialis

Flexor carpi ulnaris

Flexor digitorum superficialis

Abductor pollicis longus

Flexor digitorum profundus

Pronator quadratus

Extensor digitorum

Gracilis

Gluteus maximus

Quadratus femoris

Pectineus

Rectus femoris

Sartorius

Biceps femoris

Gracilis

Gastrocnemius

Tibialis anterior

Soleus

Fibularis (peroneus) longus and brevis

B. Close body openings by contracting

Has a broad origin; single tendon of insertion

Strap-like with an expanded belly; great ability to shorten but NOT very powerful

Fascicles are short and attach obliquely to a central tendon that runs the length of the muscle; do NOT shorten as much but are more powerful.

A rigid bar that moves on a fixed point

The fixed point upon which a lever moves

The applied force

The resistance

Radius

Elbow joint

Biceps brachii

Distal end of forearm, hand, and anything you are holding

Effort is applied at one end of the lever; the load at the other; fulcrum somewhere in between

Effort applied at one end of the lever; the fulcrum located at the other; load between them

Effort applied between the load and the fulcrum

Origin: zygomatic arch and zygomatic bone Inerstion: angle and ramus of mandible

Origin: temporal fossa Insertion: coronoid process of mandible

Origin: molar region of maxilla and mandible Insertion: orbicularis oris

Origin: zygomatic bone and infraorbital margin Insertion: skin and muscles of upper lip

Origin: manubrium of sternum and medial clavicle Insertion: mastoid process

Origin: transverse processes of cervical vertebrae Insertion: anterolateral portion of first two ribs

Origin: iliac crest Insertion: lower margin of 12th rib

Origin: lateral condyle of femur and lateral meniscus Insertion: proximal tibia

third-class

Most skeletal muscles of the body act as third-class lever systems.

synergist.

Synergists are muscles that help the prime mover by contracting at the same time to assist in the movement or stabilize a part so the movement is more effective.

chewing.

The muscles of mastication are inserted on the mandible, causing movement of the jaw during chewing.

tongue.

The suffix -glossus means tongue.

External intercostals

The eleven pairs of the external intercostals lie between adjacent ribs on each side to elevate ribs and increase volume of thoracic cavity during inspiration.

rectus abdominis.

The rectus abdominis is a pair of medial long muscles that are separated from each other by the linea alba running vertically between them. These muscles contribute to the anterior abdominal wall.

trapezius.

Trapezius is named for its shape, not its action.

adductor. pronator. levator. tensor.

pollicis.

Pollicis does not describe the shape of a muscle. Pollicis comes from the root pullex, which means thumb.

trapezius. quadratus. rhomboid.
piriformis.

rectus.
Muscles such as the rectus abdominis run parallel along the anterior abdominal wall.

oblique and rectus muscles.

Rectus abdominis and external oblique are two large muscles of the abdominal wall.

deltoid.

The deltoid is a large, thick, triangular muscle forming a rounded mass over the shoulder and upper humerus that abducts the arm.

insertion.

Insertion of a muscle is the point of attachment that is more movable.

fat content of the muscle.

No muscle names indicate fat content.

its shape.

The deltoid is a muscle named according to its shape.

pennate

The extensor digitorum muscle is an example of a pennate muscle.

Second-class levers have great strength but are slow and have little range of motion.

Second-class levers sacrifice their speed for greater strength.

Masseter

The zygomaticus is innervated by the facial nerve.

hypoglossal

All of the extrinsic tongue muscles are innervated by the hypoglossal nerve.

The sternocleidomastoid

The sternocleidomastoid divides the neck into two triangles.

External intercostals

The diaphragm increases the vertical dimensions of the thoracic.

rectus abdominis.

The linea alba is found in the rectus abdominis muscle.

deltoid

The pectoralis minor is considered a rotator cuff muscle.

anconeus

The anconeus assists the triceps brachii in forearm extension.

Flexor carpi ulnaris

Extensor digitorum extends the wrist and fingers.

iliopsoas

The prime mover for flexion of the thigh is the iliopsoas muscle.

sartorius.

The femoral nerve innervates the sartorius.

Vastus lateralis

The vastus lateralis is a common site for injections in infants who have poorly formed buttocks.

quadratus femoris.

The quadratus femoris is innervated by L5 and S1.

tibialis anterior.

The tibialis anterior dorsiflexes the foot.

irritation of the tibialis anterior.

Shin splints are caused by irritation of the tibialis anterior. A stress fracture of the tibia and tibia fascia inflammation are also referred to as shin splints.

False

The synergist is a muscle that assists the muscle primarily responsible for a given action.

False

The gluteus maximus is responsible for extension of the thigh.

True

Circular muscles close openings when they contract.

False

The degree of relative movement is greater in the pectoral girdle because the pectoral girdle is the most flexible ball-and-socket joint in the body, with nine muscles across each shoulder joint to insert on the humerus.

False

The end of the muscle that remains stationary when the muscle contracts is the origin.

True

Insertion is the point that moves when the muscle contracts.

True

The semimembranosus, semitendinosus, and biceps femoris belong to the muscle group known as "hamstrings."

True

Both the rhomboideus major and minor are responsible to steady, retract, and rotate the scapula.

True

The trapezius inserts on the clavicle and the acromion process and spine of the scapula to elevate, retract, and rotate the scapula.

False

The pectoralis major originates on the sternal end of the clavicle, sternum, cartilage of ribs, and aponeurosis of external oblique muscle.

True

The sternothyroid muscle originates on the sternum and inserts on the thyroid cartilage.

True

The deltoid is the prime mover of arm abduction when all of the fibers are contracted simultaneously.

False

The deltoid muscle is named for its triangular shape.

True

Joints are the fulcrums, and bones act as levers. Muscle contraction provides the movement.

False

Lifting your head off your chest is an example of a first-class lever.

True

The fascicular pattern is circular when the fascicles are arranged in concentric rings. Muscles with this arrangement surround external body openings.

False

Parallel muscles are relatively weak, but move the load a greater distance. A pennate muscle is best suited for a heavy load.

False

Muscle TISSUE may be named for the type of metabolism (that is, glycolytic or oxidative fibers). However, a whole muscle is not named this way because whole muscles contain a mix of skeletal muscle tissue types.

Skeletal Muscle-Striated/voluntary
Cardiac Muscle-Striated/Involuntary
Smooth Muscle-Nonstriated/Involuntary

Producing Body Movements
Stabilizing Body Positions
Regulating Organ Volume
Moving Substances within the Body
Producing Heat

-Attached to Bones and moving parts of the skeleton
-Striated/Voluntary

Found only in the heart
Striated/Involuntary

Located in the walls of hollow internal structures such as blood vessels, airways, the stomach, and the intestines.

-Nonstriated/Involuntary

,Epimysium
Perimysium
Endomysium

(These 3 form tendons and attach to bones)

Each skeletal muscle is a seperate organ composed of hundreds to thousands of cells, which are called Muscle Fibers

The entire muscle is wrapped in Epimysium

Surrounds bundles of 10-100 or more muscle fibers called fascicles

A small bundle of muscle fibers

Endomysium wraps each individual muscle fiber

Each muscle fiber is covered by a plasma membrane called a sarcolemma

tunnel in from the surface toward the center of each muscle fiber.

The muscle fibers cytoplasm

a network of fluid-filled, membrane-enclosed tubules that store calcium ions required for muscle contraction

a. a reddish pigment, similar to hemoglobin in the blood
b. an oxygen-binding protein found only in muscle fibers

cylindrical structures that extend along the entire length of the muscle fibers

2 types of myofibrils,thin filaments
thick filaments

a contractile unit in a striated muscle fiber (cell) extending from one Z disc to the next Z disc

A contractile protein that is part of the thin filaments in muscle fibers

a wasting away of muscle

an increase of muscle fiber diameter owing to the production of more myofibrils, mitochondria, ect...

an electrical signal sent to a skeletal muscle so it can contract

The neuron that delivers a muscle action potential

A single muscle neuron along with all the muscle fibers it stimulates

The region of the sarcolemma near the axon terminal

The space between the axon terminal and sarcolemma

The synapse formed between the axon terminals of a motor neuron and the motor end plate of a muscle fiber

1. Release of acetylcholine-
2. Activations of ACh receptors
3. Generation of muscle action potential
4. Breakdown of ACh

enzyme that breaks down the neurotransmitter

the repeating sequence of events that causes a filament to slide

1. Splitting ATP
2. Forming Crossbridges
3. Power Strokes
4. Binding ATP and detaching

A sustained, partial contraction of portions of the skeletal or smooth muscle

A state of limpness in which muscle tone is lost

Energy rich molecule that is unique to muscle fibers

a small amino acid-like molecule that is synthesized in the liver, kidneys, and pancreas.

a series of cytosolic reactions that produces 2 ATP's by breaking down a glucose molecule to pyruvic acid

The process that occurs when oxygen levels are low as a result of vigorous muscle activity, most of the pyruvic acid is converted to lactic acid

a series of oxygen requiring reactions that produce ATP in mitochondria

The inability of a muscle to contract forcefully after prolonged activity

refers to the added oxygen , over and above the oxygen consumed at rest, that is taken into the body after exercise

The number of impulses per second

recording of a muscle contraction

a brief contraction of all the muscle fibers in response to a single action potential in its motor neuron

a brief delay that occurs between application of the stimulus and beginning of contraction

repetitive power strokes are occurring, generating tension or force of contraction

Power strokes cease because the level of Ca2+ in the sarcoplasm is decreasing to the resting level

when stimuli arrive one after another to cause larger contraction
unfused (incomplete)

A sustainted but wavering contraction
fused (complete)

A sustained contraction in which individual twitches cannot be detected

Resistant to fatigue and are capable of prolonged, sustained contractions

Moderately high resistance to fatigue

Intense movements of short duration but fatigue quickly

the tension developed by the muscle remains almost constant while the muscle changes its length

The tension generated is not enough to exceed the resistance of the object to be moved and the muscle does not change its length

Iirregular transverse thickenings of the sarcoloma

Intrinsic rhythm of heart contractions

In smooth muscle, thin filiments attach to these structures

A state of continued partial contraction

The attachment of a muscle to the stationary bone

The attachment of a muscle to a movable bone

The fleshy portion of the muscle between the tendons

painful inflammation of the tendons, tendon sheaths and synovial membranes of the joint

Muscle that causes a desired action

Relax while prime movers contract

help the prime mover function more efficiently by reducing unnecessary movement

Stabilize the origin of the prime mover so that the prime mover can act more effeciently

one-sided paralysis of the muscles of facial expression as a result of damage or disease of the facial nerve

Two eyes are not properly aligned

Protrusion of an organ through a structure that normally contains it

The ability of tissue to return to its original shape after contration or extension

Oxygen carrying protein in muscle fibers (cells)

Invagination of the epimysium that divides muscles into bundles

The membrane of a muscle fiber (cell) especially of a skeletal muscle fiber

An electrical signal that propagates a long the membrane of a neuron or muscle fiber

A sustained partial contraction of portions of a skeletal or smooth muscle in response to activation of stretch receptors

Commone neurotransmitter used to signal muscle contraction

A threadlike structure extending longitudinally through a muscle fiber consisting mainly of thick filaments (myosin) and thin filaments (actin, troponin, and tropomyosin)

A fibrous membrane covering, supporting and separating muscles

Invagination of the perimysium separating each individual muscle fiber

A network of saccules and tubes surrounding myofibrils of a muscle fiber comparable to endoplasmic reticulum, functions to reabsorb Ca inos during relaxation and to release them to cause contraction

Inability of a muscle to maintain its strength of contraction or tension; may be related to insufficient oxygen, depletion of glycogen and/or lactic acid build up

Membrane enclosed sac in a synaptic end bulb that stores neurotransmitters

A tissue specialized for contraction, composed of smooth muscle fibers located in the walls of hollow internal organs, and innervated by autonomic motor neurons

The contractile unit of a myofiber

A synapse between the axon terminals of a motor neuron and the sarcolemma of a muscle fiber (cell)

Fibrous connective tissue around muscles

The ability of muscle tissue to stretch when it is pulled

Requiring oxygen

A small bundle or cluster especially of nerve or muscle fibers. Also called Fasciculus

The record or tracing produced by a myograph that measures and records the force of muscle contractions

Region of the sarcolemma of a muscle fiber that includes acetylcholine receptors which bind ACh released by synaptic end bulbs of somatic neurons

An enzyme found in neuromuscular junctions and in neuron synapses that quickly breaks down acetylcholine preventing continuous stimulation of the postsynaptic cell

Protein that functions in muscle contraction

Enlargment of an organ owing to enlarged cells, rather than increasing the number of cells; growth of new myofibrils within the endomysin of indivdule muscle cells

The cytoplasm of a muscle fiber (cell)

The group of muscles cells controlled by one motor neuron

Small cylindrical invaginations of the sarcolemma of striated muscle fibers that conduct muscle action potential towards the center of the muscle fiber

A complex of three units in a muscle fiber compose of the trasvers tubules and the sarcoplasmic reticulum teminal cisterns on both sides of it

The ability of cells or parts of cells to actively generate force to undergo shortening for movements

Protein that functions in muscle contraction

A muscle that is not under conscious control

A muscle that is under conscious control

A muscle that is attached to the bones of the skeleton

Involuntary muscle found inside many internal organs of the body

Muscle tissue found only in the heart

Muscle attached to the skeleton, making movement possible

Strong connective tissue that attaches a muscle to bone

Muscle that straightens a joint

Muscle that bends a joint

1. Contractibility
2. Excitability
3. Extensibility
4. Elasticity

The arrangement of thick and thin myofilaments

If a stimulus causes one member of a motor unit to contract then all members of THAT motor unit will contract and they will do so maximally

isometric

isotonic

the sarcomere

a motor unit

the warm up period in muscles, where you get a stair step appearance with out changing the voltage

your muscles would not contract. the disease is called myasthenia gravis (grave disease)

aka neuromuscular spindle...it is responsible for keeping the correct width of the sarcomere

It carries messages to the muscle

it carries messages away from the muscle and to the brain/spinal cord

there is a perimysium that surrounds each fascicle in a skeletal muscle

a fascicle is a group of muscle fibers

it is the outermost connective tissue, it covers the skeletal muscle

eccentrically located

an envelope that seperates muscle fibers

It covers one muscle fiber, it is found just under the endomysium

It is a subunit of a muscle fiber

it is a subunit of a fascicle...many muscle fibers create ONE fascicle

It is a subunit of a myofibril

a cell membrane

1. cistern
2. tubular portion/fenestrated window

it is the bag like portion and it is loaded with calcium ions when relaxed

it connects one cistern to another

Thick and thin myofilaments

it is the area(on a myofibril)between the z-discs...so there are both thick and thin myofilaments

it is the area of overlap between thick and thin myofilments

it is the area of thick myofilaments...this area becomes smaller as the muscle contracts

where there are only thing myofilaments

it is connective tissue, a plate in the form of a disc...the thin myofilaments attatch to the z-line