Anatomy Unit 2 Study Guide

The ion, _________ now diffuses into the sarcoplasm and binds to the regulatory protein, _________, found within the thin filament.

calcium, troponin

In _____________ joints, adjoining bones are united by cartilage and they lack a joint cavity.

cartilaginous

The deep __________ __________ is located between the hypodermis and the dermis. It nourishes the hypodermis and the structures located within the deeper portions of the dermis.

dermal plexus

Tendonitis

is an inflammation of a tendon, not of a tendon sheath. Causes (overuse injury or infection), symptoms (pain, swelling, tenderness) and treatments (rest, ice, anti-inflammatory drugs).

First- and second- degree burns are considered _______-_______ __________.

partial-thickness burns

Mature skeletal muscle tissue has some ability to regenerate because if its ____________ ________.

satellite cells

Dermis- Reticular layer- 80%

-Thick layer of dense irregular connective tissue - Its extracellular matrix contains thick bundles of interlacing collagen fibers (strength and resilience) and elastic fibers (stretch-recoil) that run in many different planes. - Site of Cleavage/Tension Lines and Flexure Lines, rich in nerve endings, and blood vessels (dermal plexus & sub papillary plexus), and embedded within the dermis are the appendages of the skin.

The skin performs a variety of functions:

1. Protection - heat, infection, cushions, chemicals, abrasions, UV rays 2. Water retention 3. Insulator- regulate loss of heat from body 4. Excretion through sweat 5. Sensory receptors

Myopathy (path = disease)

Any disease of muscle

Boils and Carbuncles

Infection and inflammation of hair follicles and sebaceous glands that has spread into the underlying hypodermis. A boil can be likened to a giant pimple; carbuncles are composite boils. The common cause is bacterial infection.

Athlete's Foot

Itchy, red, peeling condition of the skin between the toes, resulting from fungal infection.

The more superficial ________ _________, located just below the dermal papillae, supplies the more superficial dermal structures, the dermal papillae, and the epidermis.

sub-papillary plexus

The 2 types of cartilaginous joints are:

synchondrosis and symphysis

Importance of satellite cells in skeletal muscle growth:

- During youth, satellite cells fuse into the existing muscle fibers to help them grow. - Following injury to a muscle, satellite cells proliferate in the damaged muscle tissue and start producing proteins to repair the injury. - Some satellite cells fuse with surrounding muscle fibers; others remain as satellites. - The regeneration capacity of skeletal muscle tissue is not complete, and severely damaged tissue is replaced primarily by scar tissue.

Vitiligo

An abnormality of skin pigmentation due to a loss of melanocytes, characterized by light spots surrounded by areas of normally pigmented skin. It can be cosmetically disfiguring, especially in dark-skinned people. An autoimmune disorder.

Alopecia

Any condition involving absence or loss of hair. Male pattern baldness, the most common type, is technically named Androgenic Alopecia.

The layer that would be found between the Stratum __________ and Stratum ____________ in thick skin is the Stratum Lucidum.

Granulosum, Cornem

Melanoma: where it arises, what it looks like, growth and metastasis, and cure

- a cancer of melanocytes often arising from existing moles, usually appearing as an expanding dark patch - the most dangerous kind of skin cancer - melanoma cells metastasize rapidly - most people do not survive this cancer if the lesion has grown over 4 mm thick. - resistant to chemotherapy and current immunotherapy

Squamous cell carcinoma: where it arises, what it looks like, growth and metastasis, and cure

- arises from the keratinocytes of the stratum spinosum - the lesion appears as a scaly, irregular, reddened papule (small, rounded elevation) - tends to grow rapidly and metastasize if not removed - cure by surgical removal in 99% of cases

The epidermis is avascular, keratinized stratified squamous epithelial tissue that contains 4 distinct types of cells:

1. Keratinocytes- most abundant; produces keratin, a tough fibrous protein giving the epidermis its protective properties, and are connected to one another by desmosomes 2. Dendritic cells (Langerhans cells/ macrophages)- initiate immune response 3. Tactile epithelial cells (or Merkel cells)- receptors in touch; few in number 4. Melanocytes (melanin cells)- spider shaped cells responsible for making the dark skin pigment melanin. Melanin is phagocytized by keratinocytes

What are the 6 types of synovial shapes in the body and the movements they allow?

1. Plane Joint: articular surfaces are flat planes, short gliding movements are allowed, gliding does not involve rotation around any axis. Ex) inter-tarsal and inter-carpal joints, vertebra 2. Hinge Joint: cylindrical end of one bone fits into a trough on another bone. Angular movement (flexion and extension) is allowed in one plane. Ex) elbow, ankle, knee, and joints between phalanges. 3. Pivot Joint: rounded end of one bone fits into a ring that is formed by another bone plus an encircling ligament. Rotation is allowed. Ex) proximal radio-ulnar joint, joint between atlas and axis. 4. Condyloid Joint: egg-shaped articular surface of one bone fits into an oval convex surface. Allows moving bone to travel side to side (abduction-adduction) and back and forth (flexion-extension). Ex) metacarpo-phalangeal joints (knuckles) 5. Saddle Joint: each articular surface has concave and convex surfaces. Allows moving bone to travel side to side (abduction-adduction) and back and forth (flexion-extension). Ex) carp-metacarpal joints of the thumbs. 6. Ball-and-socket Joint: spherical head of one bone fits into round socket of another. Allows moving bone to travel side to side (abduction-adduction), back and forth (flexion-extension), and rotation. Ex) shoulder and hip joints.

Layers of the Epidermis and structures found at each, listed from deep to superficial are:

1. Stratum Basale- one row of actively mitotic stem cells with some becoming part of the more superficial layers 2. Stratum Spinosum- several layers of keratinocytes unified by desmosomes 3. Stratum Granulosum- 1-5 layers of flattened cells, organelles deteriorating. 4. Stratum Lucidum (thick skin only) 5. Stratum Corneum- 20-30 layers of dead cells

The 6 types of synovial joints are:

1. plane joints 2. hinge joints 3. pivot joints 4. condylar joints 5. saddle joints 6. ball-and-socket joints

Psoriasis

A chronic inflammatory condition characterized by reddened epidermal papules covered with dry, silvery scales. The scales result from an over proliferation of the epidermis, and the pink color is due to widened capillaries in the dermis. Relatively common, it may be an autoimmune condition triggered by bacterial products. One effective treatment for psoriasis employs a drug that slows epidermal growth and that is activated by exposure to UV light.

Rosacea

A chronic skin eruption produced by dilated small blood vessels of the face, particularly those of the nose and cheeks, causing flushing of the face. Papule's and acne-like pustules may or may not occur. More common in women, but tends to be more severe when it occurs in men. Cause is unknown, but stress, some endocrine disorders, and anything that produces flushing (hot beverages, alcohol, sunlight, etc.) can aggravate this condition.

Actinic Keratosis

A precancerous lesion of the skin composed of rough, scaly spots that can range in size from a pinhead to larger than a quarter. These lesions may feel like sandpaper and may look like an abrasion that does not heal. They are a precursor to squamous cell carcinoma and are common in sun-damaged skin. Treatment with creams or surgery removes the damaged cells. Once a lesion is diagnosed, screening for further lesions is essential.

ABCDE rule for recognizing melanoma:

A, Asymmetry: the two halves of the spot or mole do not match B, Border irregularity: the borders have indentations and notches C, Color: the pigment spot contains several colors, including blacks, browns, tans, and sometimes blues and reds D, Diameter: larger than 6mm E, Elevation: above the skin surface improves diagnosis

Angular movements: abduction and adduction (move a body part along a frontal plane)

Abduction is movement of a limb away from the body midline. Adduction is the opposite of abduction: the movement of a limb toward the body midline.

Sliding Filament Theory, step 2

Action potential triggers calcium ions to be released from the terminal cistern of the sarcoplasmic reticulum, allowing calcium ions to flood the sarcoplasm

In indirect attachments, the connective tissue extends well beyond the end of the muscle fibers to form either a cordlike tendon or a flat sheet called a(n) ___________________; connecting a muscle to the body part it moves.

Aponeurosis

Second-class lever system- arrangement and example:

Arrangement of the elements is fulcrum-load-effort. In the body: second-class leverage is exerted when you stand on tip-toe. The effort is exerted by the calf muscles pulling upward on the heel; the joints of the ball of the foot are the fulcrum; and the weight of the body is the load.

First-class lever system- arrangement and example:

Arrangement of the elements is load-fulcrum-effort. In the body: a first-class lever system raises your head off your chest. The posterior neck muscles provide the effort; the atlanto-occipital joint is the fulcrum; and the weight to be lifted is the facial skeleton.

The immediate threat to life from serious burns is a catastrophic loss of body fluids.

As fluid seeps from the burned surfaces, the body quickly loses water and essential salts. This dehydration in turn leads to fatal circulatory shock; that is, inadequate blood circulation caused by the reduction in blood volume.

Sliding Filament Theory, step 3

Calcium ions bind to troponin, troponin changes shape, removing the blocking action of tropomyosin, actin active sites are exposed

Angular movements: circumduction

Circumduction is moving a limb or finger so that it describes a cone in space. This is a complex movement that combines flexion, abduction, extension, and adduction in succession.

Sliding Filament Theory, step 4

Contraction; myosin cross bridges alternately attach to actin and detach, pulling the actin filaments toward the center of the sarcomere. this ratchet movement is repeated many times during a single contraction. release of energy by ATP hydrolysis powers the cycling process. Power stroke causes filaments to slide.

4 Step Cycle of Thick-Thin Filament Interaction, step 3

Cross Bridge Detachment: When another ATP binds to the myosin head, the link between the myosin head and actin weakens, and the myosin head detaches

4 Step Cycle of Thick-Thin Filament Interaction, step 1

Cross Bridge Formation: The activated myosin head binds to actin, forming a cross bridge. Inorganic phosphate is released, and the bond between myosin and actin becomes stronger

On the palms of the hands and the soles of the feet, the Dermal Papillae lie atop larger mounds called _____________ ___________. These elevate the overlying epidermis into Epidermal Ridges or Friction Ridges, which create fingerprints, palm prints, and footprints.

Dermal Ridges

In ___________ _________ _________ the diseased muscle fibers lack a sub membrane protein called dystrophin, which links the cytoskeleton of the muscle fiber to the extracellular matrix.

Duchenne Muscular Dystrophy

The most common and most serious form of Muscular Dystrophy is _________ ___________ __________, which is inherited as a sex-linked recessive disease. This means that females carry and transmit the abnormal gene, but it is expressed almost exclusively in males. Is usually diagnosed when the boy is between 2 and 6 years old. Active, apparently normal children become clumsy and start to fall frequently as their muscles weaken. The disease progresses from the pelvic muscles to the shoulder muscles to the head and chest muscles. Victims rarely live past age 30 and usually die of respiratory infections or respiratory failure.

Duchenne Muscular Dystrophy

________________ is a mysterious chronic-pain syndrome of unknown cause. Its symptoms include severe musculoskeletal pain, fatigue, sleep abnormalities, and headache. It affects about 2% of all people, mostly women. The most common sites of pain are the lower back or neck, but for a condition to be identified as ___________, pain must be present in at least 11 of 18 standardized points that are spread widely over the body. Not all of these points are over muscles, and muscle problems do not seem to be the primary cause; it is commonly mistaken for myofascial pain syndrome. _____________ is treated with antidepressants, exercise, and pain relievers.

Fibromyalgia

Structural classifications of joints include:

Fibrous joints Cartilaginous joints Synovial joints

Angular movements: flexion and extension (movements that occur primarily in the sagittal plane)

Flexion decreases the angle between the bones, bringing these bones closer together. Extension is the reverse of flexion and occurs at the same joints. It increases the angle between the joining bones and is a straightening action.

Movements at synovial joints:

Gliding Angular Movements: Flexion, Extension, Abduction, Adduction, Circumduction Rotation: Medial Rotation, Lateral Rotation

This causes the ____ -bands and _____ -bands to shorten while the _____ -bands stay the same length.

I, H, A

Dermis- Papillary layer- 20%

Most superficial layer of dermis, it is areolar connective tissue containing very thin collagen and elastic fibers. It includes the Dermal Papillae (fingerlike projections that extend into the overlying epidermis) which increase the surface area for exchange of gasses, nutrients, and waste products between these layers.

____________ __________ is a group of inherited muscle-destroying diseases that generally appear in childhood. The affected muscles enlarge with fat and connective tissue while the muscle fibers degenerate.

Muscular Dystrophy

In _________ ______ _________, pain is caused by tightened bands of muscle fibers that twitch when the skin over them is touched. The sensitive areas of skin are called trigger points. _________ ________ _________ is mostly associated with overused or strained postural muscles, and the pain is often felt some distance from the trigger point, in predictable places called reference zones. This syndrome is very common, affecting up to half of all people, mostly from 30 to 60 years old. The pain is treated with non steroidal anti-inflammatory drugs and by stretching the affected muscle. Massage also helps, and exercising the affected muscle can lead to long-term recovery.

Myofascial Pain Syndrome

The site where a motor neuron excites a skeletal muscle fiber is called a _______________ ____________. This junction is a chemical synapse, consisting of the points of contact between the axon terminals of a motor neuron, and the motor end plate of a skeletal muscle fiber.

Neuromuscular Junction

Sliding Filament Theory, step 1

Neurotransmitter acetylcholine (ACh) released diffuses across the synaptic cleft and attaches to acetylcholine receptors on the sarcolemma and down the T tubules

Impetigo

Pink, fluid-filled, raised lesions that are common around the mouth and nose. They develop a yellow crust and eventually rupture. This contagious condition, caused by a Staphylococcus infection, is common in school-aged children.

4 Step Cycle of Thick-Thin Filament Interaction, step 2

Power-Stroke: ADP is released and the activated myosin head pivots, sliding the thin myofilament toward the center of the sarcomere creating a ratchet-like movement

4 Step Cycle of Thick-Thin Filament Interaction, step 4

Reactivation of Myosin Head: ATP is hydrolyzed to ADP and inorganic phosphate. The energy released during hydrolysis reactivates the myosin head, returning it to the cocked position

Sliding Filament Theory, step 5

Removal of calcium phosphate ions by active transport into the sarcoplasmic reticulum after the action potential ends

Rotation: medial rotation and lateral rotation

Rotation is the turning movement of a bone around the longitudinal axis. This motion occurs along the transverse plane. Rotation of the limbs may be directed toward the median plane or away from it. For example, in Medial Rotation of the lower limb, the limb's anterior surface turns toward the median plane of the body; Lateral Rotation is the opposite movement.

Cleavage Lines/Tension Lines occur in the reticular dermis, they are:

Separations or less dense regions between the collagen bundles form the invisible Cleavage Lines or Tension Lines of the skin which occur all over the body (they run longitudinally in the skin of the limbs and head and in circular patterns around the neck and trunk) and are important for surgeons to know so that incisions made parallel to these lines gape less and heal faster than incisions made across cleavage lines.

Cold Sores (Fever Blisters)

Small, painful, fluid-filled blisters that usually occur around the lips and in the mucosa in the mouth. They are caused by the herpes simplex virus, which localizes in nerve cells that supply the skin, where it remains dormant until activated by emotional upset, fever, or UV radiation.

Functional classifications of joints include:

Synarthroses (immovable joints) Amphiarthroses (slightly movable joints) Diarthroses (freely movable joints)

___________ joints are the most movable joints of the body, and all are diarthroses (freely movable).

Synovial

Impulses traveling down the ____ ________ stimulate the release of calcium from the terminal cistern.

T tubule

Where it abuts the T tubule, the sarcoplasmic reticulum forms sac-like bulges called terminal cisternae. One _____ _______ plus two adjacent ________ ______ is known as a triad.

T tubule, terminal cisterns

____ __________ are deep invaginations of the sarcolemma that run between each pair of terminal cisterns.

T tubules (transverse tubules)

Sliding Filament Theory, step 6

Tropomyosin blockage restored, blocking actin active sites; contraction ends and muscle fiber relaxes

The dermal blood vessels consist of two vascular plexuses, a plexus is:

a network of converging and diverging vessels

Now the myosin binding sites on _________ are exposed.

actin

The electrical current generated along the muscle cell's membrane is called an _________ __________ and this is called the "excitation" phase of muscle contraction.

action potential/nerve impulse

Muscle relaxation is a(n) ___________ process and muscle contraction is a(n) _____________(channel) process

active, passive

Second-degree burns

all epidermis and the upper part of the dermis are damaged. Symptoms resemble those of first-degree burns, but blisters also appear as fluid accumulates between the epidermal and dermal layers. The skin regenerates with little or no scarring in 3 to 4 weeks if care is taken to prevent infection.

The variations in skin color in humans result from differences in both the _______ and _______ of melanin produced. The other factor influencing skin color is ___________ production.

amount, type. Vitamin D

Muscles that oppose or reverse a particular movement act as ____________.

antagonists

Third-class lever system- arrangement and example:

arrangement of the elements is load-effort-fulcrum. In the body: flexing the forearm by the biceps brachii muscle exemplifies third-class leverage. The effort is exerted on the proximal radius of the forearm; the fulcrum is the elbow joint; and the load is the hand and distal end of the forearm.

The term __________ describes over 100 kinds of inflammatory or degenerative diseases that damage the joints. All forms have the same initial symptoms: pain, stiffness, and swelling of the joint.

arthritis

When actin is exposed, the myosin heads _______ to actin, forming a ________ ______.

bind, cross bridge

A ________, a latin word meaning "purse", is a flattened fibrous sac lined by a synovial membrane. They occur where ligaments, muscles, skin, tendons, or bones overlie each other and rub together.

bursae

During this time, the change in the membrane triggers the opening of voltage-gated __________ channels found within the SR membrane.

calcium

Torn cartilage

cartilage tears in the knee (most common) often happen when a meniscus is simultaneously subjected to both high compression and shear stresses. For example, a tennis player lunging to return a ball can rotate the flexed knee medially with so much force that it tears both the joint capsule and the medial meniscus attached to it. Because cartilage is avascular, it can rarely repair itself; thus, torn cartilage usually stays torn.

The energy stored in this bond allows myosin to assume a _________ position (or "high energy" position).

cocked

Hypodermis aka Superficial Fascia aka Subcutaneous Layer

consists of both areolar and adipose connective tissue, but adipose tissue predominates. Besides storing fat, the Hypodermis anchors the skin to the underlying structures (mostly to muscles), but loosely enough that skin can slide relatively freely over those structures; ensuring many blows just glance off our bodies. Also a good insulator. Even though hypodermis is not part of integumentary system, it still shares some of the skin's functions

Third-degree burns

consume the entire thickness of the skin and thus are full-thickness burns. All dermis and epidermis is destroyed and some hypodermis. The burned area appears white, red, or blackened. Although the skin might eventually regenerate, it is usually impossible to wait for this because of fluid loss and infection. Therefore, skin from other parts of the patients body must be grafted onto the burned area. Such a graft, in which an individual is both donor and recipient, is called an autograft.

As all sarcomeres shorten in the myofibril, the muscle shortens resulting in ______________.

contraction

This marks the beginning of the ________ ________ _______ phase of muscle contraction.

excitation-contraction coupling

In _________ joints, adjoining bones are united by collagen fibers and lack a joint cavity.

fibrous

Some synergists hold a bone firmly in place so that a prime mover has a stable base on which to move a body part. Such synergists are called ___________.

fixators

From the deep part of the dermis arise the skin surface markings called __________ _________. These result from a continual folding of the skin, often over joints, where the dermis attaches tightly to underlying structures.

flexure lines

Most joints fall under which type of functional classification?

freely movable (diarthroses)

Joints can be classified by __________ or ________.

function, structure

________ _________ focuses on the amount of movement allowed.

functional classification

A _____________ is a type of fibrous joint only occurring in the articulation of a tooth with its socket; which is also called a peg-in-socket joint. The connecting ligament is the short periodontal ligament and functionally: are immobile (synarthroses)

gomphosis

The difference in skin color from melanin is due to the rate of melanin removal by the keratinocytes. Those of you who are pale-skinned, your keratinocytes have a ________ degradation rate of melanin. If you are darker, then your keratinocytes ______ ______ ___ _______ ___ _________.

high, don't digest the melanin as quickly.

Bursitis

inflammation of the bursa, usually results from a physical blow or friction, although it may also be caused by arthritis or bacterial infection. In response, the bursa swells with fluid. Severe cases of bursitis may be treated by injecting inflammation-reducing drugs into bursa.

Cardiac muscle tissue

involuntary, branching chains of cells, striated, uni- or bi-nucleate, located in walls of heart

Smooth muscle tissue

involuntary, non-striated, uni-nucleate, located in walls of hollow internal organs Ex) stomach

An example of synergists that help prime movers by adding a little extra force to the movement being carried out:

is latissimus dorsi, functions in adduction as well as extension of the shoulder because it crosses the shoulder both posteriorly and medially

An example of synergists that help prime movers by reducing undesirable extra movements that the prime mover may produce:

is pectoralis major, a flexor of the shoulder, will act as a synergist to latissimus dorsi to prevent extension and produce straight adduction.

An example of an antagonist:

is the latissimus dorsi is the antagonist of the pectoralis major.

Basal cell carcinoma: where it arises, what it looks like, growth and metastasis, and cure

is the least malignant (capable of invasion and spreading) and most common of the skin cancers. cells of the stratum basale proliferate, invading the dermis and hypodermis, causing tissue erosion there. most common lesions of this cancer are dome-shaped, shiny nodules; these nodules later develop a central ulcer and a pearly, beaded edge. grows relatively slowly and metastasis (spreading/invading to other areas) seldom occurs. cure by surgical removal in 99% of cases

An example of fixators:

is the muscles that fix the scapula when the arm moves. Muscles that maintain posture and stabilize joints also act as fixators.

An example of a prime mover (agonist):

is the pectoralis major, for flexing the arm at the shoulder. Sometimes, two muscles contribute so heavily to the same movement that both are called agonists.

The rigid elements of the skeleton meet at sites called __________, or _______________.

joints, articulations

3 pigments contribute to skin color:

melanin (the most important), carotene, and hemoglobin

Although dark-skinned people have a darker melanin, more granules (site of melanin production), and more pigment in each melanocyte, they do not have more ____________ in their skin.

melanocytes

fast glycolytic fibers

metabolic characteristics: - contract fastest, pathway for ATP synthesis: anaerobically - low myoglobin content, many glycogen stores, extremely prone to fatigue structural characteristics: - pale pink, large fiber diameter, few mitochondria and capillaries. common in the muscles of the upper limbs, best suited for lifting heavy object for brief periods

slow oxidative fibers

metabolic characteristics: - contract slowest but deliver prolonged contractions - pathway for ATP synthesis: aerobically - high myoglobin content and extremely resistant to fatigue structural characteristics: - dark red, very thin fiber size, large number of mitochondria, and rich in capillaries found in postural muscles of the lower back, best suited for maintaining posture.

fast oxidative fibers (intermediate type)

metabolic characteristics: - intermediate contraction speed between the rate of slow oxidative and fast glycolytic, pathway for ATP synthesis: aerobically, high myoglobin content, intermediate fatigue rate between slow oxidative and fast glycolytic structural characteristics: - light red/dark pink color, medium sized fiber diameter, large number of mitochondria and rich supply of capillaries abundant in the muscles of the lower limbs, best suited for moving the body for long periods during locomotion

The axon of a motor neuron branches to innervate a number of fibers in a skeletal muscle. A motor neuron and all the muscle fibers it innervates are called a _________ _______.

motor unit

Noninfectious disorders of skeletal muscle include:

muscular dystrophy, myofascial pain syndrome, and fibromyalgia

Inside there are rod-shaped organelles with alternating A and I bands called _________ that make the cell look striated.

myofibrils

The thread-like proteins that cause contraction are the thick, or __________ filaments, and the thin, or _______ filaments.

myosin, actin

A dislocation (luxation)

occurs when the bones of a joint are forced out of alignment. This injury is usual accompanied by sprains, inflammation, pain, and difficulty moving the joint. The jaw, shoulder, finger, and thumb joints are most commonly dislocated.

First-degree burns

only the epidermis is damaged. symptoms include redness, swelling, and pain: the typical inflammatory reaction to tissue damage. Generally, first-degree burns heal in a few days without special attention. Ex) sunburn

The attachment of the muscle on the less movable bone is called the __________ of the muscle, whereas the attachment on the more movable bone is called the muscle's ____________.

origin, insertion

Then the _______ _______ occurs and their heads pivot to pull the thin filaments toward the ________ of the sarcomere.

power stroke, center

A muscle that has the major responsibility for producing a specific movement is the ______ ________, or ________ of that motion.

prime mover, agonist

The plasma membrane of muscle cells is called the _____________.

sarcolemma

The contractile units are called ______________.

sarcomeres

An elaborate smooth endoplasmic reticulum whose interconnecting tubules surround each myofibril like the sleeve of a loosely crocheted sweater surrounds your arm is a

sarcoplasmic reticulum (SR)

Each skeletal muscle fiber contains 2 sets of tubules that participate in the regulation of muscle contraction:

sarcoplasmic reticulum and T tubules (transverse tubules)

The _____________ ____________ is specialized to store and release _____________ to trigger contraction.

sarcoplasmic reticulum, Ca2+ (calcium ions)

The ____________ __________and the __________ _________ store large quantities of calcium ions (Ca2+). These ions are released when the muscle is stimulated to contract.

sarcoplasmic reticulum, terminal cisterns

As the number and size of the myofibrils increases during activities such as weight lifting, the fibers enlarge. Skeletal muscle is multinucleated, and the enlarged fibers need additional nuclei to direct and support the formation of new proteins. Small immature muscle cells, called ________ ______, are scattered in the muscle tissue outside the muscle fibers. These cells fuse with the fibers, contributing the additional nuclei needed as the fibers enlarge. Thus, muscle fibers do not increase in number by dividing mitotically, rather, they increase in diameter by building more contractile proteins and myofilaments.

satellite cells

During the late fetal period and thereafter, skeletal muscle fibers are surrounded by scattered ____________ _______, which are immature cells that resemble undifferentiated myoblasts.

satellite cells

Along with the skin itself, the integumentary system includes several derivatives of the epidermis. These ________ ___________ include nails, hair and hair follicles, sebaceous (oil) glands, and sweat glands. Although they derive from the epithelial cells of the epidermis, they all extend into the dermis.

skin appendages

Gliding

sliding the flat surfaces of two bones across each other.

In a __________, the ligaments reinforcing a joint are stretched or torn. Common sites are the lumbar region of the spine, the ankle, and the knee. Partly torn ligaments eventually repair themselves, but they heal slowly because ligaments are poorly vascularized. Tend to be painful and immobilizing.

sprain

A ________ _________ is based on the material that binds the bones together and on the presence or absence of a joint cavity.

structural classification

Melanocytes respond to ultraviolet radiation (UVR) by increasing the production of melanin and increasing its transfer to keratinocytes, the protective response we know as _____________.

suntanning

A ___________ is a type of fibrous joint held together with very short, interconnecting fibers, and bone edges interlock. Are found only in the skull and functionally: are immobile (synarthroses).

suture

The 3 types of fibrous joints are:

sutures, syndesmosis, and gomphosis.

A _____________ is a type of cartilaginous joint where fibrocartilage unites the bones. Examples are the pubic symphysis and the fibrocartilaginous intervertebral discs. Functionally: slightly mobile (amphiarthroses)

symphyses

A _____________ is a type of cartilaginous joint where hyaline cartilage unites the bones. Examples are the epiphyseal plates and the joint between the first rib's costal cartilage and the manubrium of the sternum. Functionally: immobile (synarthroses)

synchondroses

A _____________ is a type of fibrous joint held together by a ligament; for example the interosseous membrane between the radius and ulna. Functionally: can be slightly mobile (amphiarthroses) or immobile (synarthroses) depending on length of connecting fibers

syndesmoses

In addition to prime movers and antagonists, most movements also involve one or more muscles called _____________. ______________ help the prime movers, either by adding a little extra force to the movement being carried out or by reducing undesirable movements that the prime mover may produce.

synergists. Synergists

In ____________ joints, adjoining bones are separated by a joint cavity, covered with articular cartilage, and enclosed within an articular capsule lined with _________ membrane.

synovial, synovial

A _________ ___________ is essentially an elongated bursae that wraps around a tendon like a bun around a hot dog. They occur only on tendons that are subjected to friction, such as those that travel through joint cavities or are crowded together within narrow canals (as in the carpal tunnel of the wrist, for example)

tendon sheath

When the muscle is stimulated to contract, the action of the thick filaments forcefully pulls the two Z discs closer together, causing each sarcomere to shorten. As the Z discs move closer together,

the I bands shorten, and the H zone disappears completely.

There dermis has 2 regions:

the papillary dermis (top 20%) and the reticular dermis (bottom 80%)

Because joints are stressed during movement, they must be stabilized to prevent dislocation (misalignment). The stability of a synovial joint depends on 3 factors:

the shapes of the articular surfaces, the number and position of stabilizing ligaments, and muscle tone.

Bundles of myosin molecules are called _______ filaments and also contain _________ enzymes that split ATP into ADP and ___________ ___________.

thick, ATPase, inorganic phosphate

The decrease in length of the I band and the disappearance of the H zone are due to the increased amount of overlap of the ______ ______ ________ __________. The length of the thin filament has not changed. The A bands stay the same length because the length of the thick filaments also does not change.

thin and thick filaments

3 common types of joint injuries are:

torn cartilage, sprains, and dislocations

This creates a conformation change in __________, another regulatory protein found within the thin filament.

tropomyosin

Skeletal muscle tissue

voluntary, single, very long cylindrical cells, striated, multi-nucleate, located attached to bones