Anatomy lecture exam 3

Posterior Compartment

- Gastrocnemius: flexes the leg and plantar flexes the foot - Soleus: plantar flexes the foot and known collectively with gastrocnemius as the triceps surae (shares common tendons of insertion with gastrocnemius calcaneal tendon)

What does Sarcoplasmic reticulum do in skeletal muscle fibers?

- Internal membrane complex - Similar to smooth endoplasmic reticulum - Surround bundles of contractile proteins

What does Sarcolemma and T-tubules do in skeletal muscle fibers?

- Na+/ K+ pumps along sarcolemma and T-tubules - create concentration gradients for Na+ and K+

Anterior Compartment

- Tibialis anterior: primary dorsiflexor of the foot and inverts the foot - Extensor digitorum longus: dorsiflexes the foot and extends toes 2-5

What does Terminal cisternae do in skeletal muscle fibers?

- blind sacs of sarcoplasmic reticulum - serve as reservoirs for calcium ions - combine in twos with central T-tubule to form triads

the steps of cross-bridge cycling in the order they occur, starting with formation of cross-bridges between myosin and actin.

1. Cross-bridge formation (myosin binds to actin) 2. Myosin head pulls and slides actin filament, myosin releases ADP and Pi 3. Myosin head binds ATP and releases from actin. 4. Myosin head resets as it breaks down ATP into ADP and Pi.

What are some of the ways that muscles are named?

1.Location: pectoralis (chest), gluteus (buttock), brachialis (arm) 2.Size: maximus, minimus, longus, brevis 3.Shape: deltoid (triangular), quadratus (4-sided), teres (rounded) 4.Orientation of fasciculi: rectus, oblique 5.Origin and insertion: sternocleidomastoid, brachioradialis 6.Number of heads: biceps, triceps 7.Function: abductor, adductor, masseter

How much energy is made by Short-term supply via anaerobic cellular respiration?

2 ATP released per glucose molecule. the fastest one to make app

How much energy is made by Long-term supply via aerobic cellular respiration?

34 net ATP produced make the most atp

Most parts of the sarcomere shorten during contraction, but what part of the sarcomere stays the same size during contraction?

A band

Define Antagonist

A muscle working in opposition to agonist

What is the I band of the sarcomere?

Actin filaments, Z discs, and connectin - but no overlap with thick filaments.

pectoralis major

Action: Flexes shoulder, adducts and medially rotates arm, extends shoulder from flexed position Origin: Clavicle, sternum, ribs 1-6 Insertion: Humerus, lateral crest of intertubercular groove

Deltoid

Action: flexes and extends shoulder, abducts and medially and laterally rotates arm. Origin: Clavicle and scapula Insertion: Humerus, deltoid tuberosity

latissimus dorsi

ActionL Extends shoulder, adducts and medially rotates arm. Origins: T7-L5, scapula, sacrum, iliac crest Insertion: Humerus, in medial crest of intertubercula groove

Of the three systems that make energy for muscle cells, which one uses oxygen and makes the most ATP?

Aerobic cellular respiration

pelvic diaphragm

(Coccygeus & levator ani)extends from ischium and pubis to sacrum and coccyx

Hamstrings

(biceps femoris, semitendinosus, semimembranosus), share common origin on ischial tuberosity, insert on the leg, function in thigh extension and movement of the knee

What is atrophy?

(changes in muscle from lack of exercise) decreasing muscle fiber size results from lack of exercise can arise from temporary reduction in muscle use causes decrease in muscle tone and power initially reversible, but dead fibers not replaced with extreme atrophy, loss of muscle function permanent muscle replaced with connective tissue

state their origins and what effect contraction for that muscle has on the tongue: Hyoglossus

(originates hyoid bone) depresses and retracts tongue

state their origins and what effect contraction for that muscle has on the tongue: Genioglossus

(originates on mandible) protracts tongue

pectoralis minor

(originates on ribs, inserts on scapula)Deep to pectoralis major, Helps depress and protract the scapula when contracted, shoulders hunch forward.

state their origins and what effect contraction for that muscle has on the tongue: Palatoglossus

(originates on soft palate) elevates posterior part of tongue

state their origins and what effect contraction for that muscle has on the tongue: Styloglossus

(originates on styloid process of temporal bone) elevates and retracts tongue

Define Masseter

(prime mover) Elevates and pulls the mandible anteriorly (protracts), [ Most powerful and important masticatory muscle]

Quadriceps femoris

(rectus femoris, vastus lateralis, vastus intermedius, vastus medialis),prime mover of knee extension and composite muscle with four heads

What does sarcoplasm do in skeletal muscle fibers?

- Cytoplasm of muscle fibers (cells comprising muscle) - Contains typical cellular structures e.g., Golgi apparatus, ribosomes, vesicles - Has specialized cellular structure

Define Belly

Between the origin and insertion

Orbicularis oculi muscle

Circular muscle fibers surround orbit (Closes eye)

Orbicularis oris

Closes mouth, puckers lips

Occipitofrontalis muscle

Connects with epicardial aponeurosis (galea aponeurotica) to form epicranius, Frontal belly raises eyebrows, Occipital belly retracts scalp slightly

Rhomboid major and minor

Deep to the trapezius, Runs inferolaterallly from spinous processes of vertebrae to scapula, (Help elevate, retract, and inferiorly rotation of scapula)

tranversus abdominis

Deepest muscle, fibers projecting transversely, forms aponeurosis anteriorly

Understand that skeletal muscle has a great blood supply (why?)

Deliver oxygen and nutrients, removing waste products

Anterior (front) [feet]

Dorsiflex the foot, extend the toes, or both.

Corrugator supercilii muscle

Draws eyebrows together; Brings eyebrows together vertical wrinkles

Temporalis

Elevates and pulls the mandible posteriorly (retracts), Broad, fan-shaped muscle

triceps brachaii

Extends elbow and shoulder, adducts arm

What is the trapezius muscle?

Extends neck, moves scapula, supports arm, Insertions:Clavicle and scapula. (Origins: Occipital protuberance, superior nuchal line to C7, C7 - T12)

what is the Splenius capitis muscle?

Extends, rotates, laterally flexes neck, Insertion: Superior nuchal line and mastoid process, (Origin on C4-T6)

Lateral compartment

FIbularis longus: powerful foot evertor, weak plantar flexor inserts on plantar foot

serratus anterior

Fan-shaped muscle between ribs and scapulaAgonist in scapula protraction (Helps stabilize scapula, superior rotator of the scapula)

Retinacula of the forearm

Fibrous bands at the wrist formed from deep fascia, Help hold tendons close to bone

Define Origin

Fixed, less mobile end(s) of the muscle; proximal; occasionally, multiple

Posterior (back) [feet/ankle]

Flex the foot at the ankle

brachioradialis

Flexes elbow. Anterolateral forearm and synergistic in elbow flexion

biceps brachaii

Flexes shoulder and elbow, supinates forearm and hand

brachialis muscle

Flexor elbow and most powerful flexor of forearm

Define muscle tone

Generated by involuntary nervous stimulation of muscle Some motor units stimulated randomly at any time Change continuously so units not fatigued Tension called the resting muscle tone Do not generate enough tension for movement Decreases during deep sleep

scalene muscles

Helps elevate first and second ribs during forced inspiration

What is hypertrophy?

Hypertrophy (changes in muscle from a sustained exercise program) increase in skeletal muscle size results from repetitive stimulation of fibers results in more mitochondria larger glycogen reserves increased ability to produce ATP more myofibrils that contain larger number of myofilaments

Describe the 3 systems used to make ATP in skeletal muscle.

Immediate supply via the phosphagen system Short-term supply via anaerobic cellular respiration Long-term supply via aerobic cellular respiration

internal obliques

Immediately deep to external oblique, fibers projecting superomedially (Forms aponeurosis projecting anteriorly)

What does Sarcolemma and T-tubules do in skeletal muscle fibers?

Invaginations of the sarcolemma

Describe how isometric and isotonic contractions are different

Isometric contractions Muscle tension insufficient to overcome resistance Contraction of muscle and increased tension Muscle length the same Force generated by muscle isn't enough to overcome resistance. No movement of muscle. Muscle contracts, tension increases, muscle length stays the same Isotonic contractions Muscle tension > resistance Movement! Tone same but length change; concentric or eccentric

What is the 'neuro' part of the neuromuscular junction?

It's the axon terminal of a motor neuron that contacts the muscle cell

what is Sternocleidomastoid muscle

Laterally flex, rotate head. If both contract, flex neck, Insertion: Mastoid process and superior nuchal line, (Origin: Sternum and clavicle.)

Lateral (sides) [leg]

Leg muscles contain two synergistic muscle that area very powerful evertors of the foot and weak plantar flexor muscles

what muscles help us chew and eat?

Mastication: chewing: involves elevation/ depression of mandible and excursion to grind teeth together, temporomandibular joint (TMJ)

Pectineus

Medial thigh. Adduct and flex

Define Insertion

More mobile end; distal More moveable attachment of a muscle Usually pulled toward the origin

Forearm muscles

Most move the wrist, fingers, or both, Called extrinsic muscles of the wrist and hand (Anterior group: flexion, with abduction, adduction, and a little pronationPosterior group: Extension of wrist, hand, fingers)

Define Action

Movement that occurs when muscle contracts

Define Agonist

Muscle that causes an action when it contracts Muscle that contracts to produce a movement

Define Synergist

Muscle that work together to cause a movement Muscle assisting agonist May contribute to tension close to insertion

erector spinae

Muscles within erector spinae are superficial to the deep muscles of the vertebrae. The action of these muscles is to maintain erect posture (fight gravity!). Erector spinae is the entire group of superficial muscles support the vertebral column, consists of three subgroups, the iliocostalis group (which is lateral), the longissimus group (intermediate) and the spinalis group (most medial).

identify the origin and insertion of levator palpebrae superioris

Origin: lesser wing of sphenoid behind eye Insertion: skin of eyelid

identify the origin and insertion of orbicularis ori

Origin: maxilla, frontal bones Insertion:circles around orbit of eye, inserts near origin

identify the origin and insertion of Corrugator supercilii

Origin: nasal bridge, orbicularis oculi Insertion: skin of eyebrow

levator scapulae

Originates form transverses processes of cervical vertebrae, Inserts on superior angle of scapula(Elevates and inferiorly rotates the scapula)

Trapezius (scapula)

Originates on occipital bone and vertebral column, inserts onto clavicle and scapula.Shaped muscle: diamond, (Extends from skull and vertebral column to pectoral girdle can elevate, depress, retract or rotate scapula)

What does Sarcolemma and T-tubules do in skeletal muscle fibers?

Plasma membrane of a skeletal muscle fiber

Define Prime mover

Plays major role in accomplishing movement

Describe how muscle fiber types are classified.

Primary means used for supply ATP Type of contraction generated slow oxidative (SO), fast oxidative (FO) and fast glycolytic (FG)

depressor anguli oris

Pulls corners of the mouth inferiorly to frown

Depressor labii inferioris

Pulls down lip; frowning, pouting

Thoracic muscles & breathing

Scalenes, intercostals, and diaphragm

how they are structurally different

Skeletal Muscle Responsible for locomotion, facial expressions, posture, respiratory movements, other types of body. Smooth Muscle Some functions: propel urine, mix food in digestive tract, dilating/constricting pupils, regulation blood flow Can be autorhythmic Cardiac Muscle Heart: pumps blood through the blood Autorhythmic

where you find each type of muscle tissue? if it has voluntary or involuntary contractions?

Skeletal muscle is found throughout the body, attached to bones via tendons. voluntary Smooth muscle is found on walls of hollow organs, blood vessels, eye, glands, skin. involuntary Cardiac muscle is found on the thick middle layer of the heart. involuntary

Why is skeletal muscle rich in blood vessels and innervation?

Skeletal muscles need to bring in a lot of oxygen and nutrients and quickly remove wastes to function properly. Nerves allow us to control contraction consciously.

What does the sarcoplasmic reticulum do in muscle cells?

Stores calcium and releases it when the action potential travels into the T tubule.

External oblique

Superficial, fibers directed inferomedially muscular along lateral abdominal wall (forms Aponeurosis anteriorly, inferioly, becomes cordlike inguinal ligament)

levator ani

Supports pelvic viscera and provides sphincter-like action in anal canal and vagina (Iliococcygeus and pubococcygeus)

For epimysium, where is it located within the muscle?

Surround whole skeletal muscle

For endomysium, where is it located within the muscle?

Surrounds and electrically insulates each muscle fiber

Describe the structure of the neuromuscular junction.

Synaptic knob, Motor end plate, Synaptic cleft

The muscle fibers arranged in the orbicularis oculi have a circular arrangement -- what does this mean?

They are arranged in a ring around an opening.

What do you know to be true for "slow oxidative fibers"?

They use aerobic respiration to make ATP, are a darker red color because they have myoglobin, and usually have slower contractions than fast fibers

What are the different types of connective tissue in skeletal muscle?

Three types of connective tissue in skeletal muscle is epimysium, perimysium, endomysium.

The occipitofrontalis muscle has its origin on the occipital bone and inserts into the skin of the eyebrows and nose. What would you expect its action to be?

To wrinkle the forehead, as it moves the scalp and eyebrows

Evert

When the soles is turned outward or away from the the midline

Invert

When the soles of the soles of the foot is turned inward or toward the midline

Tensor fasciae latae

abducts and medially rotates the thigh, attaches to lateral thickening of fascia lata termed iliotibial tract

supraspinatus

abducts the arm, used when starting to execute pitch

Lateral compartment muscle

abducts the thigh

infraspinatus and teres minor

adduct and laterally rotate arm slows down arm on completion of pitch, end throw

medial compartment muscles

adduct the thigh

levator anguli oris

also used to smile, draws mouth upward

The muscle whose action is opposite that to the action of the agonist is the _____.

antagonist

Muscles moving the thigh (hip joint)

anterior compartment muscles, medial compartment muscles, lateral compartment muscles, and posterior compartment muscles.

iliopsoas

anterior thing and flex

Where is the rectus abdominus located?

anterior-most part of the abdominal wall, under the rectus sheath.

The erector spinae muscles (spinalis, longissimus, and iliocostalis)

are the superficial trunk muscles that maintain posture and keep the spine erect.

soleus

broad muscle deep to gastrocnemius plantar flexes the foot known collectively with gastrocnemius as the triceps surae shares common tendons of insertion with gastrocnemius calcaneal tendon

Intrinsic muscles of the tongue

changes shape during of the tongue when chewing and speaking

What are the muscle fiber arrangements.

circular, parallel, convergent, and pennate

Describe Circular Muscles

concentrically arranged fascicles, (Create a sphincter; control material passage through an opening) [ ex: orbicularis oris/ muscle around mouth]

For perimysium, where is it located within the muscle?

connective tissue surrounding muscle bundles

Quadratus lumborum

connects from the twelth rib to the iliac crest and also extends the spine.

internal intercostals

deep to external intercostals, fibers at right angles to external intercostals, depresses ribs during forced expiration

superior oblique muscle

depresses and turns the eye laterally

Which one of the following muscles is most likely to be involved in a frown?

depressor anguli oris

The following muscles are all used in breathing. Which one is the prime mover?

diaphragm

extensor digitorum longus

dorsiflexes the foot and extends toes 2-5

levator labii superioris

draws lip upward, sneer

inferior oblique muscle

elevates and turns eye laterally

5 characteristics of skeletal muscle tissue

excitability, conductivity, contractility, elasticity, extensibility

As part of the posterior compartment muscles of the thigh, the hamstrings

extend the hip

Anterior compartment muscles

extend the knee or flex the thigh

adductor magnus

extends and laterally rotates the thigh

what is the Semispinalis capitis muscle?

extends head, bends head to one side, or rotates head, Insertion: Occipital bone, [ Origins C4—T6 (cervical vertebrae 4 to thoracic vertebrae 6) ]

External intercostals

extends inferomedially from superior rib to adjacent inferior rib, elevates ribs during inspiration, expanding cavity, movement like lifting a bucket handle

Describe Convergent Muscles

fascicles merge toward a common attachment site (Can pull in varying directions, but not as hard as parallel muscles) [ ex: pectoralis major/ pectoral muscle]

Describe Pennate muscles

fascicles organized as if part of a large feather, •Fibers pull at an angle to the tendon (Generate more tension but don't pull their tendons as far as parallel muscles) [ex: extensor digitorum (forearm muscle), rectus femoris (thigh muscle), deltoid (shoulder muscle)]

Describe Parallel/ Straight muscles

fascicles run parallel to muscle's long axis (Sometimes have an expanded central belly; high endurance) [ ex: rectus abdominis/ the muscle that makes the abs]

Posterior compartment muscles

flex knee and extend the thigh

Generally speaking, the anterior arm muscles (ie, biceps brachii)

flex the elbow

sartorius

flexes and laterally rotates thigh and flexes and medially rotates leg

Gracilis

flexes the leg (as well as adducting the thigh)

Which set of muscles moves the tongue?

genioglossus, palatoglossus, styloglossus

Gastrocnemius

has two thick bellies forming the "calf" flexes the leg and plantar flexes the foot

State the subgroups that make up the superficial muscles and help with maintaining posture.

iliocostalis, longissimus, spinalis

What muscles are on the hip/thigh?

iliopsoas, pectineus, adductor magnus, gracilis, sartorius, tensor fasciae latae, gluteus maximus, hamstrings (biceps femoris, semitendinosus, semimembranosus)

extrinsic muscles of the tongue

insert in tongue and allow change in shape and movement (originates on head and neck structures), includes: genioglossus, hyoglossus, palatoglossus, styloglossus

The _____ is the more mobile end of the muscle.

insertion

diaphragm

internally placed, dome-shaped muscle partitions thoracic and abdominal cavities most important muscle associated with breathing fibers conversing toward a fibrous central tendon contracts during inspiration central tendon pulled inferiorly increases vertical dimensions of thoracic cavity PRIME MOVER

what are the deep group of trunk muscles?

intertransversarii, rotatores, multifidus, and interspinales muscles responsible for moving the vertebral column and keeping us upright, connect from one vertebrae to the next, and allow the spine to extend, rotate, and laterally flex.

what does Intercalated discs things do for these heart cells

junctions joining cardiac cells composed of desmosomes and gap junctions

gluteus maximus

largest of three gluteal muscles,chief extensor of the thigh, laterally rotates the thigh

what is Rotation and abduction in the neck

lateral and posterior groups of the neck muscle

rectus abdominis (abdominal muscle)

long muscle extending vertically, extends entire length of anteromedial abdominal wall, partitioned into four segments by fibrous tendinous intersectionsenclosed within a fibrous sleeve, rectus sheath

Longissimus group

medial to iliocostalis group, inserts on vertebrae transverse processes (composed of capitis, cervical, and thoracic parts)

subscapularis

medially rotates arm, used when winding up for a pitch

Iliocostalis group

most laterally placed, has cervical, thoracic, and lumbar parts

Spinalis group

most medially placed, inserts on spinous processes of vertebrae(composed of cervical and thoracic parts)

Due to its size and locations of its origin and insertion, the trapezius muscle has multiple actions. One of those actions is

moves/stabilizes the scapula.

what is Flexion in the neck

muscles deep within the neck along the anterior and lateral margins of the vertebral bodies

The crural muscles

muscles that move the ankle, foot, and toes (have Anterior, lateral, posterior sides)

What protein will you find in thick filaments?

myosin

Dorsiflex

occurs when the ankle bends raising the toes upward, and this decreases the angle between the dorsal side of the foot and the tibia.

levator palpebrae superioris

opens upper eyelid

Muscles that move the arm and rotator cuff

pectoralis major, latissimus dorsi, deltoid; subscapularis, infraspinatus, supraspinatus, and teres minor

Muscles in the posterior compartment of the leg, like the gastrocnemius muscle,

plantar flex (push down) the foot.

what is Extension in the neck

posterior neck muscles attached to occipital bone

fibularis longus

powerful foot evertor, weak plantar flexor inserts on plantar foot

tibialis anterior (shin)

primary dorsiflexor of the foot inverts the foot

How much energy is made by phosphagen system?

provides an additional 10 to 15 seconds of energ

inferior rectus muscle

pulls eye inferiorly and medially

lateral rectus

pulls eye laterally

medial rectus

pulls eye medially

superior rectus

pulls eye superiorly and medially

The masseter is the prime mover of the muscles involved in chewing (mastication). It

pulls the jaw up and forward.

Define what a sarcomere is

repeating, contractile units overlapping thick and thin filaments, have Z discs at each end

what does am Autorhythmic pacemaker things do for these heart cells ?

responsible for repetitious, rhythmic heartbeat stimulates cardiac muscle cells rate and force of heartbeat controlled by autonomic nervous system

zygomaticus major

retracts and elevates corner of mouth (smiling)

zygomaticus minor

retracts and elevates upper lip (smiling)

What are the parts found in skeletal muscle fiber?

sarcoplasm, sarcolemma, sarcoplasmic reticulum, T-tubule, terminal cisternae, myofibrils

3 types of muscle tissue

skeletal, cardiac, smooth

Describe the structure of cardiac muscle cells

striated, branched, contain many mitochondria, and are under involuntary control

four rectus muscles of the eye

superior, inferior, lateral, medial rectus

coccygeus

supports pelvic organs

What are the rotator cuff muscles?

supraspinatus, infraspinatus, teres minor, subscapularis

The sternocleidomastoid has its origins on the manubrium and clavicle and inserts onto the mastoid process. When both contract equally,

the neck flexes.

What does a tendon do (and how are its fibers arranged - regular or irregular?)

the role of dense regular connective tissue is to dissipate forces to bones.

The medial and lateral pterygoids

together they elevate, protract, and move mandible side to side

What are muscle that act on the scapula?

trapezius, levator scapulae, rhomboid major and rhomboid minor, pectoralis minor, serratus anterior

What are the muscle of the arm?

triceps brachii, biceps brachii, brachioradialis, and brachialis muscles

Plantar flex

when the ankle bends in the direction that points the toes and plantar side of the foot downward.

what are the names that are in the sarcomere?

z discs, thin filaments, thick filaments, M line, A band, I band, H zone.