anatomy 2

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

Vertebra prominens

"special" name for 7th cervical vertebra derived from the fact that its relatively large spinous process can be readily seen and/or felt through the skin at the base of the posterior neck

Atlas

"special" name of 1st cervical vertebra; articulates with occipital condyles to form a hinge-type joint that allows you to flex & extend your head, as in nodding "yes".

Axis

"special" name of 2nd cervical vertebra; has a dens/odontoid process that articulates with the atlas to form the atlanto-axial joint, which is a pivot-type joint that allows you to rotate your head from side to side, as in indicating "no".

? may be categorized according to two characteristics:

(1) How they manufacture energy [make ATP] and (2) How quickly they contract. Based on these criteria, types of skeletal muscle cells include (a) Slow oxidative fibers (b) Fast glycolytic fibers, and (c) Fast oxidative fibers.

Frontal belly of Epicranius

(1) Location: Overlies frontal bone (2) Actions: Pulls scalp forward; furrows brow

Occipital belly of Epicranius

(1) Location: Overlies occipital bone (2) Action: Pulls scalp backward

Superior & Middle conchae/turbinates

(2 of each) -- project from lateral walls of nasal cavity. ethmoid

Specific types of abdominal hernias:

(a) Inguinal hernia -- involves the protrusion of a small portion of the small intestine or greater omentum [a part of the peritoneal membrane] through the inguinal canal, a passage that courses through the aponeurosis of the external oblique in the groin [inguinal] region; (b) Umbilical hernia -- involves the protrusion of a small portion of the small intestine or greater omentum though the middle of the rectus abdominis; (c) Hiatal hernia -- involves protrusion of a small part of the upper stomach through an opening in the diaphragm called the esophageal hiatus, which serves as the normal passageway for the esophagus through the diaphragm. Interestingly, in cases of inguinal & umbilical hernias, the herniated component can sometimes be felt and/or seen as a bulge in the skin.

functions of the 4 pairs of thin sheet like muscles of anterior and lateral abdominal wall/trunk muscles:

(a) help support abdominal organs; (b) flex the trunk & vertebral column; (c) laterally bend & rotate trunk & vertebral column; (d) increase intra-abdominal pressure to facilitate defecation, micturition [emptying urinary bladder], vomiting, delivery [childbirth], and forced expiration.

Slow oxidative fibers

(also called red, slow-twitch fibers) contract slowly & produce ATP by aerobic means (metabolic reactions that involve the use of oxygen & the production of large amounts of ATP). red due to the abundant myoglobin (an oxygen-binding pigment) they contain. Relative to fast glycolytic fibers, they contain a larger number of mitochondria (the sites of aerobic metabolism), have a richer supply of capillaries, are very resistant to fatigue, are relatively thin in diameter, and do not generate much contraction power. Many are in muscles responsible for maintaining posture for long periods of time.

Fast glycolytic fibers

(also called white, fast-twitch fibers) contract quickly and produce ATP anaerobically via glycolysis (a metabolic process that does not require oxygen and makes little ATP). pale in color because they contain little myoglobin. And relative to slow oxidative fibers, fast glycolytic fibers have fewer mitochondria, are supplied with fewer capillaries, are less resistant to fatigue, contain more actin & myosin and myofibrils, have a larger diameter, and generate much more powerful contractions. There are many fast glycolytic fibers in the arm muscles that are capable of lifting heavy objects for brief periods of time.

Thoracic cage or Bony thorax

(includes Sternum, Ribs, & Costal cartilages)

"intracapsular" ligaments

(inside the joint cavity) anterior & posterior cruciate ligaments. The names of these two ligaments are derived from the fact that they cross over one another inside the knee joint cavity, & the term "crus" means cross (consider the word "crucifix"). Each cruciate ligament extends between the distal femur & proximal tibia.

"extracapsular" ligaments

(outside the joint cavity) ligaments include the fibular & tibial collateral ligaments. The fibular collateral ligament extends from the femur's lateral epicondyle to the fibula the tibial collateral ligament extends from the femur's medial epicondyle to the tibia.

Serratus anterior

(sometimes called the "boxer's muscle") a. Location/Description: Lies deep & inferior to pectoral muscles on lateral aspect of rib cage; runs from lateral chest toward shoulder b. Insertion: Scapula c. Action: Protracts (pulls forward) shoulder, specifically scapula

Erector spinae / Sacrospinalis

Only muscle that moves vertebral column and trunk a. Description/Location: Complex group of muscles located deep in the back on both sides of the vertebral column b. Action: Extension of vertebral column (spine) & trunk; provide for erect posture of spine; when these muscles contract on just one side of the vertebral column, they help bend the spine laterally. c. Clinical info: Lifting a heavy load or moving suddenly from a bent-over position is potentially injurious to the erector spinae muscles and intervertebral discs; the erector spinae/sacrospinalis muscles readily go into painful spasms following back injuries.

Inferior turbinates/conchae (concha is singular)

Paired bones that project from inferior aspect of lateral walls of nasal cavity

abdominal hernia

Part of the anterior and lateral abdominal wall/trunk muscles: abnormal protrusion of an abdominal component (a portion of an internal organ) out of the abdominal cavity through a weak point in a skeletal muscle of the abdominal wall.

Muscles That Move the Arm (Humerus)

Pectoralis major latissimus dorsi deltoid rotator cuff muscles: supraspinatus, infrspinatus, teres minor, subscapularis

Sarcolemma

Plasma membrane of muscle fibers/cells many long, rod(cylinder)-shaped organelles named myofibrils. Myofibrils consist of subunits called sarcomeres, the basic units of contraction in skeletal muscle. A myofibril is like an entire train and the sarcomeres are like the individual cars of that train. Specifically, a sarcomere is that portion of a myofibril between two consecutive Z lines (Z dics).

Ischium

Posterior, inferior (posteroinferior) portion of hip bone. (b) Ischial tuberosity -- big bump that bears your weight when you're sitting and serves as an attachment site (the origin) for the hamstring muscles. (c) Ischial spine -- sharp point that angles into the pelvic outlet & can hinder delivery.

Skeletal Muscle Functions

Produces movement -- skeletal muscle primarily moves bones, but it also moves the skin to produce facial expressions. b. Maintains posture -- this function of skeletal muscle is provided by muscle tone (tension / partial contraction) that maintains body position without causing movement. c. Stabilizes joints -- this function of skeletal muscle is also provided by muscle tone (tension / partial contraction); is especially important relative to the stability of the shoulder & knee joints. d. Generates heat -- muscle contractions produce heat that helps maintain normal body temperature.

Greater & Lesser trochanters of femur

Projections on proximal femur to which muscles attach

Arches of the Feet

Provide the foot with a certain amount of springiness (resilience). Are maintained by the (a) interlocking shapes of foot bones, (b) ligaments that bind the bones of the feet and (c) tendons of muscles that attach to those bones.

Muscles That Act on the Anterior & Lateral Abdominal Wall & Trunk

Rectus abdominis The three following muscles are in each anterolateral aspect of the abdominal wall: External oblique internal oblique transverse abdominis

Borders of Nasal Cavity

Roof of nasal cavity - Floor of nasal cavity -- Lateral walls of nasal cavity Anterior wall of nasal cavity

Abnormal Spinal Curvatures

Scoliosis -- abnormal lateral curvature of the thoracic vertebrae. Kyphosis/Hunchback -- exaggerated posterior curvature of the thoracic vertebrae; common in elderly women because of vertebrae fractures that occur in association with osteoporosis; sometimes called "dowagers hump". Lordosis/Swayback -- exaggerated anterior curvature of the lumbar vertebrae; common in obese men and pregnant women.

bursa of knee joint

Several are associated with the knee joint, including the subcutaneous prepatellar bursa, which just as its name indicates, is located immediately beneath the skin in front of the patella. Inflammation of prepatellar bursa (a case of bursitis) is a common result of hard bumps to the kneecap.

Factors that influence the stability of synovial joints

Shapes of articular surfaces of bones - this factor actually provides significant stability in only a few synovial joints, however, it is important in regard to determining the kinds of movement that are possible at a synovial joint. ligaments muscle tone

Muscles That Move the Head & Neck

Sternocleidomastoid

Structure of Nasal Septum

Superior part of nasal septum inferior part of nasal septum -- formed by vomer bone. Anterior part of nasal septum -- formed by septal cartilage.

rotator cuff muscles location and action

Supraspinatus a. Location: Lies superior to the scapular spine on the posterior scapula; is deep to the trapezius b. Action: Helps hold head of humerus in glenoid cavity of scapula, thereby stabilizing shoulder joint (2) Infraspinatus a. Location: Lies inferior to the scapular spine on the posterior scapula b. Action: Same as supraspinatus (3) Teres minor a. Description: Small muscle that lies inferior to the infraspinatus b. Action: Same as supraspinatus (4) Subscapularis a. Location: Lies against anterior aspect of scapula b. Action: Same as supraspinatus

arrangement

The _____ of thin/actin & thick/myosin filaments in sarcomeres is responsible for the stripes (striations) seen in skeletal muscle cells

Pelvic Structure and Childbearing

The female pelvis is adapted for childbearing: It is wider, shallower, and lighter than that of a male. These features provide for more room in the true pelvis, which must be wide enough for an infant's head to pass through during birth. 2. The superior opening into the true pelvis is called the pelvic inlet, whereas the inferior opening out of the true pelvis is called the pelvic outlet. Bony components that protrude into either of these openings can cause delivery problems. Such bony protrusions that can hinder delivery include the following: (1) the sacral promontory, (2) the coccyx, and (3) the ischial spines.

actin filaments

Thin filaments are attached to the Z lines/discs at each end of a sarcomere.

muscle tone in synovial joint stability

This term refers to the tension in a skeletal muscle when it is partially contracted, yet is not causing movement. helps stabilize joints by keeping tension in the skeletal muscles & tendons that surround joints. By this means, muscles & tendons help keep the bones of some synovial joints in their proper positions. This stabilizing factor is especially important relative to the reinforcement of the shoulder joint, knee joint, and arches of the foot.

Projections that serve as sites of attachment for muscles (via tendons) & ligaments

Tuberosity Tubercle Trochanter Epicondyle

Nasal bones

Two small bones that form the bridge of the nose. (Most of the external nose consists of pieces of hyaline cartilage, not bone.)

axon terminals

When the axon of a somatic motor neuron reaches a muscle, it branches into several of these they form junctions with the sarcolemma of skeletal muscle cells.

Muscular dystrophy

a group of inherited diseases characterized by progressive deterioration & weakening of skeletal muscles. Involves defects in genes that are responsible for coding for proteins in the sarcolemma of skeletal muscle cells.

Prime mover/Agonist

a muscle that's largely responsibile for causing a given movement

Synovial joints

a) Bones are joined by a synovial membrane & a fibrous capsule. (b) Joint cavity is present. (c) Are freely movable joints (functionally, are diarthroses joints). (d) Examples: Shoulder joint, elbow joint, wrist joint, hip joint, knee joint, ankle joint, etc.

Masseter

a. Description/Location: Covers lateral aspect of mandibular ramus; bulging of it can be felt through skin when teeth are clenched b. Insertion: Mandible c. Action: mastication/chewing; biting; elevates mandible (closes jaw)

Pectoralis major

a. Description/Location: Large, superficial muscle of chest b. Insertion: Humerus c. Action: Flexes & adducts arm; pulls arm forward across chest

Platysma

a. Description/Location: Thin, sheet-like, superficial, anterior neck muscle b. Insertion: Lower margin of mandible and skin at corner of mouth c. Actions: Tenses skin in anterior neck; pulls mandible & skin at edge of mouth downward

brachioradialis

a. Description/Location: Three-headed (three-part) muscle in posterior arm b. Insertion: Olecranon process of Ulna c. Action: Extends forearm

Rhomboids

a. Description/Location: Two rectangular muscles lying deep to trapezius b. Insertion: Scapula c. Action: Along with middle fibers of trapezius, retract scapula, thereby "squaring shoulders"

Biceps brachii

a. Description/Location: Two-headed (two-part), superficial muscle in anterior arm b. Origins: Two parts of scapula, one of which is the coracoid process c. Insertion: Radial tuberosity d. Action: Flexes forearm

Latissimus dorsi

a. Description: Broad, flat, superficial muscle that extends from lower back to upper arm b. Insertion: Humerus c. Action: Extends & adducts arm; draws arm backward & downward

diaphragm

a. Description: Forms floor of thoracic cavity. Forms a complete partition that separates the thoracic and abdominal cavities. In the relaxed state, the diaphragm is dome-shaped, but as it contracts, it flattens, thereby increasing the volume of the thoracic cavity by increasing its vertical dimensions. Thus, the diaphragm is the primary muscle that provides for inspiration/inhalation. It usually contracts automatically & rhythmically during breathing, however, one can voluntarily contract it at will. b. Innervation: Phrenic nerve c. Action of diaphragm: Prime mover of inspiration. When voluntarily, strongly contracted, the diaphragm lowers and thereby increases intra-abdominal pressure, thus facilitating defecation, urination, and delivery.

Deltoid

a. Description: Forms much of the fleshy portion of the shoulder area; common site for intramuscular injections b. Insertion: Deltoid tuberosity of humerus c. Action: Abducts arm

Gluteus maximus

a. Description: Largest and most superficial of butt muscles; forms most of buttock mass; overlies sciatic nerve b. Insertion: Gluteal tuberosity on posterior Femur c. Major Action: Extends thigh

Gracilis

a. Description: Long, thin superficial muscle of most medial aspect of thigh b. Action: Adduction of thigh

Biceps femoris

a. Description: Most lateral member of group b. Origin: Ischial tuberosity (the same bump on the ischium that bears your weight when you're sitting) c. Insertion: Tibia d. Action: Flexion of leg e. Innervation: Sciatic nerve

External Oblique

a. Description: Most superficial of the three muscles in the anterolateral abdominal wall; fibers run at an angle (are oblique) b. Action: Compresses abdomen; helps rotate and laterally bend trunk

Sartorius

a. Description: Strap-like superficial muscle that runs obliquely across anterior surface of thigh to knee b. Action: Helps produce the "cross-legged" position

Semitendinosus

a. Location: Lies medial to biceps femoris b. Origin: Ischial tuberosity c. Insertion: Tibia d. Action: Flexion of leg e. Innervation: Sciatic nerve

Semimembranosus

a. Location: Primarily deep to semitendinosus b. Origin: Ischial tuberosity c. Insertion: Tibia d. Action: Flexion of leg e. Innervation: Sciatic nerve

Tibialis anterior

a. Location: Superficial, anterior leg; immediately lateral to the tibia's anterior crest b. Insertion: some Foot bones c. Action: Dorsiflexes foot (Dorsiflexion) d. Swelling of tibialis anterior and associated pain = "Shin splints"

Peroneus/Fibularis longus

a. Location: Superficial, lateral leg b. Insertion: some Foot bones c. Action: Everts foot (Eversion)

Orbicularis oculi

a. Location: Surrounds anterior aspect of eye b. Action: Closes eye; produces blinking & squinting

iliacus

a. Origin: Ilium of hip bone b. Insertion: Femur c. Action: Flexion of thigh

psoas major

a. Origin: Lumbar vertebrae b. Insertion: Femur c. Action: Flexion of thigh d. Cut of meat (what butchers call it): Tenderloin

Zygomaticus

a. Origin: Zygomatic bone b. Insertion: Skin at corners of mouth c. Action: Draws (pulls) corners of mouth upward; called the smiling muscle

Scapula (Shoulder blade)

acromion spine spine coracoid process glenoid cavity/fossa

Ball-and-socket joint

allows for a wide variety of movements; examples of ball-and-socket joints: shoulder joint & hip joint.

Hinge joint

allows for flexion & extension; examples of hinge joints: knee joint, elbow joint, and the joint formed between the atlas & occipital condyles (atlanto-occipital joint).

Pivot joint

allows for rotation; examples: atlanto-axial joint (the joint between the atlas & the axis's dens/odontoid process) and the proximal radio-ulnar joint (which allows for the particular kinds of rotation known as pronation & supination).

Sinus

an air-filled cavity within a bone. (Paranasal sinuses surround the nasal cavity and are lined with a mucous membrane.)

Myasthenia gravis

an autoimmune disease characterized by the attack of one's own immune system against one's own acetylcholine receptors on the sarcolemma (plasma membrane) of skeletal muscle cells. With the progressive loss of acetylcholine receptors, there's progressive loss of normal stimulation of skeletal muscles, and over time they become very weak.

Foramen (plural = Foramina)

an opening in a bone.

Ribs

are 12 pairs of them; all articulate posteriorly with thoracic vertebrae. First seven pairs (pairs 1-7) of ribs = True ribs, which attach directly to the sternum via costal cartilages. Last five pairs (pairs 8-12) of ribs = False ribs (1) Rib Pairs 8-10 = (2) Rib Pairs 11-12 = False ribs that are even more specifically designated as "Floating" ribs because they have no costal cartilages and have no attachment to the sternum at all. c. Intercostal spaces -- spaces between the ribs & costal cartilages that are filled with breathing-related skeletal muscles named the external intercostals (associated with inhalation/inspiration) and the internal intercostals (associated with exhalation/expiration).

Thoracic vertebrae

are larger than cervical vertebrae, but smaller than lumbar vertebrae; articulate with the posterior end of the ribs

Tarsals

are the seven bones in each foot that form the tarsus (anatomical ankle). a. Talus -- specific bone with which the distal ends of both the tibia & fibula articulate to form the ankle joint; lies between the distal tibia & the calcaneus. b. Calcaneus (Heel bone) -- specific bone that forms the heel, and to which the Achilles/calcaneal tendon of the calf muscles attaches; largest of tarsal bones

carpals

arrangement of these bones makes the wrist somewhat concave on its anterior side. A ligament named the transverse carpal ligament / flexor retinaculum covers this concavity superficially, forming the carpal tunnel. Several tendons of anterior forearm muscles and the median nerve course through this tunnel, making it very crowded. So inflammation & swelling of tendons in the carpal tunnel may very well lead to compression of the median nerve, resulting in the symptoms known as carpal tunnel syndrome.

Mandibular condyle / Head of mandible

articulates with mandibular fossa of temporal bone to form temporomandibular joint (TMJ), the only freely movable joint in the skull.

Mandibular fossa

articulates with the mandibular condyle of the mandible to form the temporomandibular joint (TMJ), the only freely moving joint in the skull.

synaptic cleft.

axon terminals and the sarcolemma are very close to one another, they do not actually touch. The gap between them is called the

Shoulder joint

ball-and-socket type joint primarily consisting of: articulation of the head of the humerus glenoid cavity/fossa of the scapula. The loose fit of the humerus's head with the particularly shallow glenoid fossa/cavity allows this joint to be the most freely moving joint in the body. prone to dislocation. little stability this joint has, is provided by rotator cuff. This cuff encircles the shoulder joint. The rotator cuff is prone to strains & tears when the arm is vigorously moved, and is thus commonly in injured in baseball pitchers.

Zygomatic process

barlike extension that projects anteriorly to meet the zygomatic bone. Zygomatic arch = Zygomatic process of Temporal bone + Zygomatic bone.

Muscles That Move the Forearm (insert on radius or ulna)

biceps brachii brachialis triceps brachii brachioradialis supinator pronator teres

Structure of a Typical Vertebra

body/centrum vetebral arch vertebral foramen processes that extend from the vertebral arch (but are not part of the arch): spinous process transverse process

Patella

bone located anteriorly to distal femur and proximal tibia; is enclosed in the quadriceps femoris tendon

rotator cuff

brings stability to shoulder joint from the tone/tension in muscles/tendons that comprise this structure encircles the shoulder joint and includes these four specific skeletal muscles: supraspinatus, infraspinatus, subscapularis, & teres minor prone to strains & tears when the arm is vigorously moved, and is thus commonly in injured in baseball pitchers.

Medial malleolus of tibia

bump on distal tibia that forms the inner (medial) bulge of the ankle

Medial & Lateral epicondyles of femur

bumps on distal femur to which the medial & lateral collateral ligaments attach.

To contract, a skeletal muscle fiber/cell must be stimulated ??

by a motor neuron of the somatic motor nervous system. number of skeletal muscle cells per motor unit varies from less than ten to several hundred. Skeletal muscles that are capable of very fine control (such as the muscles that move the fingers & eyes) have very few muscle fibers/cells per motor unit. In contrast, large muscles (such as those in the hips & thighs), where contractions are powerful, but not precisely controlled, have many muscle cells/fibers per motor unit

Osteoarthritis

called "wear-and-tear" arthritis; specifically involves degeneration of articular cartilage; it's so common it's practically part of the aging process in humans.

External acoustic (auditory) meatus

canal that leads to the eardrum & middle ear.

Meatus

canal-like passageway through a bone.

Types of Vertebrae (Listed in order from superior to inferior.)

cervical thoracic lumbar sacrum coccyx

spina bifida

characterized by failure of some laminae to completely fuse during fetal development, resulting in incompletely formed vertebral arches (and because of this, some of the spinal cord may be left exposed). Laminectomy is surgical removal of a lamina, which may be done to reach & relieve a herniated disc.

sarcomere

composed of thin (actin) filaments and thick (myosin) filaments. Thin/actin filaments are attached to the Z lines/discs at each end of a sarcomere. Thick filaments are called myosin filaments because they're primarily made out of a protein named myosin. Thick/myosin filaments are located in the central portion of a sarcomere. The thick filaments bear tiny knobs called cross bridges/myosin heads.

Perimysium

connective tissue wrapping around a bundle of skeletal muscle fibers/cells; such a bundle of cells/fibers is called a fascicle.

Endomysium

connective tissue wrapping around a single skeletal muscle cell/fiber.

Coccyx

consists (on the average) of four fused vertebrae; commonly called the "tailbone"; it can hinder delivery

Pelvic Girdle

consists of the 2 hip/coxal bones; attaches the lower limb to the trunk. Hip bone =

Ankle joint

consists of the articulation of the distal tibia & distal fibula with the talus (a specific tarsal bone). A sprain is a stretched or torn ligament of any joint, therefore a sprained ankle involves a stretched or torn ligament associated with the ankle joint, in particular.

, a muscle can perform different tasks at different times because

contains a mixture of the three fiber types, a muscle can perform different tasks at different times. For example, the gastrocnemius muscle in the calf uses its fast glycolytic fibers to propel the body in a short sprint, uses its fast oxidative fibers in long distance running, and uses its slow oxidative fibers in maintaining a standing posture.

when sarcomeres contract & shorten, the cells in which they are located ___?

contract & shorten, as do the skeletal muscle organs that those cells compose. However, during contraction, the thick/myosin filaments & thin/actin filaments themselves do not actually change in length - rather, their positions relative to one another change.

all muscle cells contain

contractile protein myofilaments: Actin Myosin

Acetabulum

deep socket in hip bone where the ilium, pubis, & ischium meet, and with which the head of the femur articulates to form the essence of the hip joint. very large opening in hip bone.

bunion

deformity of the hallux usually caused by poor-fitting shoes

Muscles Used in Breathing

diaphragm external intercostals internal intercostals

acetylcholine

diffuses across the synaptic cleft and attaches to membrane receptors on the sarcolemma of the adjacent skeletal muscle cell. If enough acetylcholine binds to the membrane receptors, it induces the initiation of an impulse on the sarcolemma.

Lateral malleolus of fibula

distal end of fibula; forms outer (lateral) bulge of the ankle

Skeletal Muscle Tissue Cells are

elongated & multinucleated. Its cells are striated. Striations = the stripes that extend across the width of the cells

The tendon of the quadriceps femoris muscle group

encloses the patella at the anterior aspect of the knee joint. And from the patella, the patellar ligament descends to attach (insert on) the tibial tuberosity.

Connective Tissue Wrappings of Skeletal Muscle and Related Features

epimysium perimysium Endomysium

Muscles of Facial Expression

epiranius oribicularis oculi orbicularis oris zygomaticus bussinator platysma

Hyperextension

extension beyond the anatomical position such as tilting the head so that the chin is pointing at the sky; hyperextension of the thigh at the hip or the arm at the shoulder are normal motions, but one cannot (at least usually not without injury) hyperextend the forearm at the elbow or the leg at the knee

The anterior & lateral abdominal wall contains

fascia (sheets of connective tissue) and four pairs of thin sheet-like muscles: the 1. rectus abdominis, 2. external oblique, 3. internal oblique, & 4. transversus abdominis.

Bursae

flat, synovial fluid-filled sacs lined with a synovial membrane; reduce friction between joint-related structures that rub against one another during movements; are located in several places where ligaments, tendons, muscles, bones, or skin overlie one another and rub together.

Muscles That Move the Hand (Wrist/Carpals, Palm/Metacarpals, & Fingers/Phalanges)

flexor carpi radialis palmaris longus flexor carpi ulnaris extensor carpi radialis extensor digitorum extensor carpi ulnaris

neuromuscular junctions or motor end plates

form junctions with the sarcolemma of skeletal muscle cells

Floor of nasal cavity

formed by palatine processes of maxilla and palatine bones (these same components form the roof of the mouth as the hard palate).

Maxilla (Maxillary bone)

forms the upper jaw and most of the hard palate. Specific parts Maxillary sinuses (paranasal sinuses) Upper jaw & central part of face Alveolar margin Palatine processes

Muscle cells have a __ blood supply

good. Well vascularized

Lumbar vertebrae

have very thick bodies, making them the sturdiest of the vertebrae (this should be expected since most of the weight-supporting job of the vertebral column is the responsibility of its lumbar region).

ligaments in synovial joint stability

help hold the bones together and help prevent excessive or undesirable motions. People who are said to be "double-jointed" do not have additional joints, but do have looser, more flexible ligaments & articular (joint) capsules.

Synergists

help prime movers by producing the same movement or by reducing undesirable movement when a prime mover contracts

Intervertebral foramina

holes between adjacent vertebrae through which spinal nerves pass.

Body of mandible

horizontal portion of mandible that forms the inferior jaw-line

Bones of Upper Limb

humerus radius ulna carpals Metacarpals phalanges

Flexion

in some instances, decreases the angle between the bones of a joint and brings them closer together; examples: bending the forearm at the elbow or bending the leg at the knee, tilting the head toward the chest, angular forward & upward movement of the thigh (femur) or arm (humerus).

Extension

in some instances, increases the angle & distance between bones; returns bones to the anatomical position after being flexed; examples: straightening the forearm at the elbow or straightening the leg at the knee from flexed positions.

Pharyngeal constrictor muscles

in the wall of the pharynx then come into play by squeezing food inferiorly through the pharynx and into the esophagus.

Weight lifting (Resistance/Strength training)

increases the diameter & strength of fast muscle fibers because it stimulates the production of contractile proteins (actin & myosin) and myofibrils. As the number and size of myofibrils increase, the fibers/cells enlarge and so does the overall skeletal muscle to which those cells/fibers belong. So, a skeletal muscle does not increase in size via mitosis (cell division) of its composite fibers, rather a skeletal muscle enlarges as the size (diameter) of its composite cells increases.

Carpal tunnel syndrome is associated with

inflammation & pain in the area of the flexor retinaculum / transverse carpal ligament and compression of the median nerve, which passes directly below the middle of the flexor retinaculum. The compression of the median nerve often leads to difficulty in moving the thumb and flexing the wrist because it's the nerve responsible for the normal stimulation of the muscles that provide those particular movements.

Sclera (the tough, white outer coat of the eyeball)

insertion for Muscles That Move the Eyeballs / Extrinsic Eye Muscles

Fast oxidative fibers

intermediate in many of their characteristics in comparison with the other two types of fibers.

Hip joint

is a ball-and-socket joint formed by the articulation of the head of the femur with the acetabulum of the hip/coxal bone.

Elbow joint

is a hinge type joint primarily consisting of the fit of the trochlea of the humerus into the trochlear notch of the ulna

Iliopsoas

is actually a composite of two muscles, the iliacus & psoas major, which extend from the ilium & vertebral column, respectively, to the anterior thigh. (1) Iliacus 2) Psoas major

Rheumatoid arthritis

is an autoimmune disease (a disorder in which the body's own immune system attacks one's own tissues). Rheumatoid arthritis specifically involves inflammation & degeneration of the synovial membrane, followed by the formation & ossification of scar tissue in the joint → the ossification of scar tissue tends to fuse bone ends together and deforms afflicted joints.

Structural Classification of Joints

is based on these two criteria: [1] the kind of connective tissue that binds the articulating bones together and [2] the presence or absence of a joint cavity between the articulating bones. Three major (general) structural classes of joints: fibrous, cartilaginous, & synovial

Functional Classification of Joints

is based upon the amount of movement allowed at a joint. For example, freely movable joints are classified as diarthroses joints. These joints predominate in the limbs, where mobility is especially important.

Bursitis

is inflammation of a bursa. Falling on one's knee can cause inflammation of the subcutaneous prepatellar bursa, which is sometimes called "water on the knee". Prolonged pressure of the elbow on a desk can cause "student's elbow" (olecranon bursitis), inflammation of the bursa located between the ulna's olecranon process and the skin.

Knee joint

is the largest & most complex joint in the body. consists of the junction of the wheel-shaped condyles of the femur with the relatively flat condyles of the tibia. articulation of the patella (kneecap) with the anterior, distal end of the femur is also associated with it

joint/articulation

junction of two or more bones hold the bones of the skeleton together, yet many allow for mobility of the skeleton

Knee joint injuries

knee joint is not very stable and is prone to injury is that the relatively flat tibial condyles do not provide a secure socket for the femur's condyles to fit into. This makes the knee joint particularly vulnerable to horizontal blows. Hard, lateral horizontal blows tend to tear the tibial collateral ligament, medial meniscus, and anterior cruciate ligament (ACL). Injuries to the anterior cruciate ligament (ACL) alone are common non-contact injuries in sports where running athletes must quickly stop and quickly change their direction of running, thus twisting a hyperextended knee. A completely torn ACL has very little healing capacity, so it must be replaced by a graft from a tendon or another ligament.

Foramen magnum

large opening in the base of the occipital bone where the lowest part of the brain (medulla oblongata) meets the spinal cord.

Lateral walls of nasal cavity

largely formed by nasal conchae/turbinates, which include the superior & middle conchae/turbinates of the ethmoid bone and the independent inferior conchae/turbinates. (The word "conchae" is plural, while "concha" is singular.)

Anterior wall of nasal cavity

largely formed by pieces of cartilage that comprise the external nasal cartilage, with a small contribution provided by nasal bones in the bridge of the nose.

Acromion of scapula

lateral projection on scapula that forms the tip of the shoulder; articulates with acromial end of clavicle.

Articular cartilage

layer of hyaline cartilage tissue that covers the articulating surfaces of the bones in a synovial joint. This smooth, slippery cartilage reduces friction in synovial joints & absorbs some of the shock to which the associated bones are susceptible. (Note that the articular surfaces of bones are not covered with the synovial membrane, but instead with the articular cartilage.)

Reinforcing ligaments

ligaments that strengthen the fibrous capsule.

Suprahyoid muscles

located above the hyoid bone pull the hyoid & larynx superiorly & anteriorly. This moves the laryngeal opening under a protective flap named the epiglottis, which normally keeps food & fluid out of the lower respiratory tract. The anterior movement of the hyoid bone helps widen the pharynx to better receive food.

Infrahyoid muscles

located below the hyoid bone pull the hyoid & larynx inferiorly to their resting positions as swallowing ends.

Cervical vertebrae

located in cervical (neck) region; are relatively small; their transverse processes have transverse foramina through which the vertebral arteries course in route to the brain. (1) Atlas (2) Axis (3) Vertebra prominens

head of femur

located on proximal end of femur; articulates with acetabulum of hip bone to form essence of hip joint.

Tibial tuberosity of tibia

located on the anterior surface of the tibia, slightly distal to its condyles; this tuberosity serves as an attachment site for the patellar ligament

medulla oblonga

lowest part of the brain

tearing of a meniscus in the knee joint

made of fibrocartilage and all cartilage is avascular

Wrist joint

mainly involves the articulation of the radius with the scaphoid & lunate bones, which are two specific carpal bones.

All muscle cells contain

mitochondria, the cellular organelles that produce ATP

Muscles That Move the Foot

most are located in the leg. Sheets of fascia separate these leg muscles into anterior, lateral, & posterior compartments. In the ankle, bands of fascia (retinacula) are arranged like "ankle bracelets'' and help hold the distal tendons of these muscles in place. specific: tibialis anterior extensor digitorum longus peroneus/fibularis longus gastrocnemius soleus

Plantar flexion

movement at the ankle that moves the foot downward; occurs when you stand on your toes.

Dorsiflexion

movement at the ankle that moves the instep (top) of the foot up & toward the shin.

All muscle produces

movement. produced when contracted and shortened either obvious external or subtle internal

Supination

moving the palm & forearm from a posterior or downward-facing position to an anterior or upward-facing position; occurs when the radius rotates around the ulna to bring these bones into a parallel position relative to one another

Pronation

moving the palm & forearm from an anterior or upward-facing position to a posterior or downward-facing position; occurs when the radius rotates around the ulna, thus crossing over the ulna to form an "X" in the forearm

Prefixes myo and sarco pertain to

muscle

muscle cells are called

muscle fibers this is because of elongated, threadlike shape

Antagonist

muscle that opposes or reverses a particular movement produced by a prime mover/agonist; when a prime mover is contracted/shortened, its antagonist is relaxed.

Sheets of fascia separate the

muscles in the forearm into anterior & posterior compartments. Most of the muscles located in the anterior compartment of the forearm are flexors of the wrist & fingers; exceptions include the pronator teres & brachioradialis. Most of the muscles in the posterior compartment of the forearm are extensors of the wrist & fingers.

Sarcomere contraction occurs when

myosin cross bridges attach to actin/thin filaments, then pivot to pull (slide) the actin filaments inward, thus shortening it because the actin filaments are attached to the Z lines which are pulled closer together as the thin/actin filaments slide inward. This action is called the sliding filament mechanism of contraction, and it is powered by ATP.

Contraction of skeletal muscle cells is ultimately controlled by

nerve cells that generate impulses that travel along the sarcolemma. These impulses are conducted from the sarcolemma deep into the muscle cells by T tubules. This promotes contraction because the impulses conveyed by T tubules stimulate the sarcoplasmic reticulum to release calcium ions, and when calcium ions are present, the cross bridges of thick/myosin filaments can bind to actin/thin filaments.

inervation

nerve supply

Retraction

non-angular movement in which a bone is moved straight back; example: "squaring" the shoulders (mainly involves the scapula).

Depression

non-angular movement in which a bone is moved straight down; example: dropping the shoulders (mainly scapula).

Protraction

non-angular movement in which a bone is moved straight forward; example: drawing the shoulder (mainly the scapula) directly forward

Elevation

non-angular movement in which a bone is moved straight up; example: shrugging the shoulders (mainly involves the scapula).

Dislocations of joints

occur when the bones of a joint are forced out of their normal alignment. After happening once, is susceptible to repeated dislocations because the first incident stretches the joint capsule & associated ligaments, and after these components are loosened, the joint is more likely to do this again

Skeletal muscles extend from

one bone to another, crossing at least one moveable joint. When a skeletal muscle contracts, it causes one of these bones to move while the other bone remains fixed/stationary. Origin -- the attachment of a skeletal muscle that remains fixed/stationary/immobile when the muscle contracts. (2) Insertion -- the movable attachment of a skeletal muscle. In the muscles of the limbs, the origin lies proximal to the insertion

Skeletal muscles extend from

one bone to another, crossing at least one moveable joint. When a skeletal muscle contracts, it causes one of these bones to move while the other bone remains fixed/stationary. a. Origin -- the attachment of a skeletal muscle that remains fixed/stationary/immobile when the muscle contracts. b. Insertion -- the movable attachment of a skeletal muscle. In the muscles of the limbs, the insertion lies distal to the origin.

Femur

only bone in thigh (not in "anatomical leg"); largest, longest, heaviest, strongest bone in body. Head Neck Greater & Lesser trochanters Gluteal tuberosity Medial & Lateral condyles Medial & Lateral epicondyles

Vertebral foramen

opening between the body/centrum and vertebral arch; all the vertebral foramina combine to form the vertebral canal through which the spinal cord passes.

Carotid canal

opening in inferior part of temporal bone that allows passage of the internal carotid artery to the brain

Mandibular foramen

opening on medial aspect of mandible that allows passage of the inferior alveolar nerve (a branch of the trigeminal nerve) to the lower teeth.

Menisci / Articular discs

pads of fibrocartilage that improve the fit between bones in certain synovial joints (occur in knee joint & temporomandibular joint); the tearing of a meniscus in the knee joint is known as a "torn cartilage" injury.

intervertebral discs

pads which help cushion the vertebrae by absorbing jolts. consists of: an outer fibrocartilage layer (called the anulus fibrosus) inner gelatinous core (called the nucleus pulposus). As we age, the intervertebral discs tend to lose water and the ligaments around them weaken -- these factors increase the risk of a herniated / slipped / ruptured disc. Such a disc protrudes posterolaterally from its normal position & may press on some spinal nerve roots extending from the spinal cord, resulting in extreme pain and/or numbness.

Perpendicular plate

partition of bone that forms the superior part of the nasal septum. ethmoid

Muscles That Move the Shoulder (Primarily Move the Scapula)

pectoralis minor serratus anterior trapezius rhomboids

Shoulder/Pectoral Girdle

portion of appendicular skeleton that attaches the upper limb to the trunk; each shoulder/pectoral girdle consists of a clavicle & a scapula

Vertebral arch

posterior arch-shaped part of vertebra; laminae (singular = lamina) are posterior portions of the vertebral arch

Mastoid process

projection located posterior & inferior to external acoustic meatus; serves as a point of attachment for some neck muscles, such as the sternocleidomastoid muscle; filled with air cavities (mastoid sinuses) that are susceptible to infection (mastoiditis) via bacteria that enter these spaces from the nearby middle ear.

Gluteal tuberosity of femur

projection on posterior aspect of femur's shaft where the gluteus maximus muscle attaches

coracoid process of scapula

projection to which one of the tendons of the biceps brachii attaches.

Generally, muscles that move portions of the limbs are located

proximally to the relatively distal parts they move. For example, muscles that move the forearm are mainly located in the arm, muscles that move the hand are generally located in the forearm, muscles that move the leg are most often located in the thigh, and muscles that the foot are generally located in the leg.

Medial & Lateral condyles of tibia

relatively flat parts on proximal tibia that articulate with the wheel-shaped condyles on the distal femur to help form the knee joint

synaptic vesicles

release a neurotransmitter chemical named acetylcholine into the synaptic cleft when a nerve impulse reaches the axon terminals

Nerves of synovial joints

richly supplied with sensory nerve fibers that innervate the articular capsule. Some of these fibers detect pain, but most monitor how much the capsule is being stretched. This monitoring of joint stretching is one of the ways by which the nervous system senses our posture & body movements.

spine of scapula

ridge on posterior scapula; skeletal muscle located above this spine: supraspinatus; skeletal muscle located below this spine: infraspinatus

Alveolar margin of mandible

ridge that bears the lower teeth; all the alveoli (sockets) of the lower teeth are in this margin.

Alveolar margin

ridge which bears the upper teeth; all the alveoli (sockets) of the upper teeth are in this margin

Fossa

shallow, basin-like depression in a bone; often serves as an articular surface.

Anterior/Tibial crest of tibia

sharp ridge on front of tibia that can be easily palpated (felt through the skin); the tibialis anterior muscle is located immediately lateral to it.

Epimysium

sheath of connective tissue around an entire skeletal muscle; the connective tissue of the epimysium extends beyond a skeletal muscle either in the form of a cord-like tendon or a broad, sheet-like aponeurosis.

types of muscle

skeletal cardiac smooth

Synovial fluid

slippery, lubricating fluid that's secreted by the synovial membrane into the joint cavity. moves into and out of articular cartilages in association with the pressure placed on joints during normal movement. This enables it to help nourish articular cartilages (remember, all cartilage is avascular).

Occipital condyles

smallish wheel-shaped projections that articulate with (form a joint with) the 1st cervical vertebra / Atlas -- this joint allows for rocking (flexion & extension) of the head as in when one indicates "yes".

Rotation

sort of a semicircular movement of a bone; occurs at shoulder joint (when humerus rotates) & hip joint (when femur rotates); occurs at joint formed between dens/odontoid process of the axis and the atlas (atlanto-axial joint

Intercostal spaces

spaces between the ribs & costal cartilages that are filled with breathing-related skeletal muscles named the external intercostals (associated with inhalation/inspiration) and the internal intercostals (associated with exhalation/expiration).

sarcoplasmic reticulum

specialized organelle in a skeletal muscle cell that releases calcium ions upon being stimulated, and these calcium ions allow for the interaction between the myosin cross bridges and actin filaments that's required for skeletal muscle contraction to occur. (At the end of contraction, the released calcium ions move back into this area)

four rotator cuff muscles & their tendons (all of which insert on the humerus) help??

strengthen & stabilize the shoulder joint. These four muscles & their tendons are arranged such that they form a nearly complete circle around the shoulder joint - this arrangement comprises the rotator cuff.

Skeletal muscles attach to their origins & insertions via

strong fibrous connective tissue that is arranged in the form of tendons or aponeuroses. Although most tendons & aponeuroses attach to bones, some attach to the skin (as do all facial muscles) or attach to sheets or strips of fibrous connective tissue.

Skeletal muscles attach to their origins & insertions via

strong fibrous connective tissue that is arranged in the form of tendons or aponeuroses. Although most tendons & aponeuroses attach to bones, some attach to the skin (as do all facial muscles) or attach to sheets or strips of fibrous connective tissue. attach to their origins & insertions via strong fibrous connective tissue that is arranged in the form of tendons or aponeuroses. Although most tendons & aponeuroses attach to bones, some attach to the skin (as do all facial muscles) or attach to sheets or strips of fibrous connective tissue.

Muscles That Move the Eyeballs / Extrinsic Eye Muscles

superior rectus inferior rectus medial rectus lateral rectus superior oblique inferior oblique

Swallowing Muscles

suprahyoid muscles pharyngeal constrictor muscles infrahyoid muscles

arthroscopic surgery

tearing of a meniscus in the knee joint Menisci are made of fibrocartilage and all cartilage is avascular. So, a torn meniscus rarely repairs itself; instead its torn pieces are often surgically removed from the knee joint. Knee joint surgery typically involves an outpatient procedure called arthroscopic surgery. Using miniaturized video and surgical equipment inserted into the joint through a small incision, the surgeon removes the cartilage fragments, and if possible, repairs torn ligaments. This procedure minimizes trauma & scarring and speeds healing. (Arthroscopic surgery can be used to operate on several joints, not just the knee.)

specific synovial joints

temproromandibular joint (TMJ) Wrist joint shoulder joint elbow joint hip joint knee joint ankle joint

False/Greater pelvis

that portion of the bony pelvis that's located superior to the pelvic brim & true/lesser pelvis, and between (medial to) the flared portions of the two ilia of the hip bones (ilia = plural of ilium).

Four of the six of extrensic eye muscles are innervated by???

the Oculomotor nerve (Cranial nerve III)

Most (but not all) of the muscles that move the forearm are located in

the arm they insert on the radius & ulna, primarily allowing them to flex & extend the forearm. Sheets of fascia (connective tissue) separate the muscles in the arm into anterior & posterior compartments. Muscles located in the anterior compartment of the arm are flexors of the forearm, whereas the muscle in the posterior compartment of the arm (the triceps brachii) extends the forearm.

Flexors of the Wrist & Fingers

-- Are located in the anterior forearm. -- Are mainly supplied (innervated) by the median nerve -- Include the following specific muscles 1. Flexor carpi radialis -- flexes wrist 2. Palmaris longus -- flexes wrist; can sometimes be identified by its long tendon 3. Flexor carpi ulnaris -- flexes wrist

Extensors of the Wrist & Fingers

-- Are located in the posterior forearm. -- Are innervated by the radial nerve -- Include the following specific muscles 1. Extensor carpi radialis -- extends wrist 2. Extensor digitorum -- extends all digits, except thumb (pollex) 3. Extensor carpi ulnaris -- extends wrist [Tennis elbow is a soreness caused by overuse of tendons of the extensors of the wrist.]

temproromandibular joint (TMJ)

-- consists of the junction of these components: head / mandibular condyle of the mandible and the mandibular fossa of the temporal bone. Because of the shallowness of the mandibular fossa, this joint is the most commonly dislocated joint in the body. Painful disorders are common in people and are often associated with tension in chewing muscles.

Palatine processes

-- form the anterior part and most [about 3/4] of the hard palate (the bony roof of the mouth).

Sprain of joints

-- is a stretched or torn ligament. Partly torn ligaments eventually repair themselves, but they heal very slowly largely because ligaments are composed of a variety of dense fibrous connective tissue (dense regular connective tissue) that has a poor blood supply

Fibula

-- much thinner & more lateral of the two leg bones; has a straight, thin stick-like shape; does not bear weight; does not really contribute to the formation of the knee joint; articulates distally with the talus; provides some stability to the ankle joint.

neck of femur

-- relatively narrow extension on which the head is located; is the weakest part of the femur and is what actually breaks in a "broken hip"; is especially susceptible to growing weaker in post-menopausal women with osteoporosis.

spinous process

-- single projection that extends posterioraly from the vertebral arch; the laminae lie at its base

Inversion

-- turning the sole of the foot so that its faces medially.

Cranial Bones

2 parietal bones + 2 temporal bones + 1 frontal bone + 1 occipital bone + 1 sphenoid bone + 1 ethmoid bone

26 bones in the vertebral column

7 Cervical vertebrae + 12 Thoracic vertebrae + 5 Lumbar vertebrae + 1 Sacrum (consists of five fused vertebrae) + 1 Coccyx (consists of [usually] four fused vertebrae) = 26 bones.

True/Lesser pelvis

= that portion of the bony pelvis that's located inferior to the pelvic brim, inferior to the false/greater pelvis, and inferior to the flared portions of the ilia

Articular/Joint capsule

= two-layered sleeve that encloses joint cavity. Outer layer = Fibrous capsule. Inner layer = Synovial membrane, which covers/lines all the internal joint surfaces, except where articular cartilage occurs.

motor unit

A motor unit consists of a single motor neuron plus all the muscle cells it is responsible for stimulating. There's always only one motor neuron per motor unit

Paranasal sinuses

Air-filled spaces that surround the nasal cavity. Are lined with a mucous membrane that is continuous with that of the nasal cavity. Are located in these bones: frontal, sphenoid, ethmoid, & maxillary bones

skin or sheets/strips of fibrous connective tissue

Although most tendons & aponeuroses attach to bones, some attach to the ??? (as do all facial muscles) or attach to

hallux

Anatomical name for big toe

Pollex

Anatomical name for thumb

Pubis

Anterior, inferior portion of hip bone. (b) The pubis of one hip bone articulates with the pubis of the other hip bone to form a cartilaginous joint called the pubic symphysis (or symphysis pubis).

Zygomatic bones

Are called the cheekbones because they form the prominences of the cheeks. Join with the temporal bone's zygomatic processes to form the zygomatic arch

Phalanges

Are the 14 bones in the five digits of each hand --

Carpals

Are the eight short bones in each hand that are tightly joined by ligaments and arranged in two rows to form the (anatomical wrist). The anatomical wrist is in the proximal part of the hand, thus, a so-called wristwatch is actually worn on the distal forearm, not on the true wrist.

carpals

Are the five bones in each hand that form the palm. Distally, the heads of metacarpals form the "knuckles" and articulate with the proximal phalanges.

Metacarpals

Are the five bones in each hand that form the palm. Distally, the heads of these form the "knuckles" and articulate with the proximal phalanges.

Fontanelles (may also be spelled Fontanels)

Are the soft spots in the fetal & infant skull that have yet to be converted to bone Advantages of: (1) Allow growth of brain and (2)Allow for slight compression of the skull during birth. Disadvantage of: Are soft, so they don't give as much protection to the brain as bone does. Are ossified (converted to bone) within two years after birth

Features shared by all synovial joints

Articular/Joint capsule Synovial fluid >> Articular cartilage >> Reinforcing ligaments -- >> Blood vessels -- even though it's true that no blood vessels are in the articular cartilages, synovial joints are, overall, quite vascular. >> Nerves --

Cartilaginous joints

Bones are joined by cartilage. (b) No joint cavity. (c) Slightly movable. (d) Examples: {1} Intervertebral joints of spine and {2} Pubic symphysis (or Symphysis pubis) -- in both of these, the articulating bones are connected by pads of fibrocartilage

Fibrous joints

Bones are tightly joined by fibrous connective tissue. (b) No joint cavity present. (c) No movement allowed (are immobile). (d) Examples: Sutures of skull.

Features of some synovial joints

Bursae and Articular discs / Menisci

Orbits / Eye sockets

Composed of parts of seven different bones. Contain eyeballs, fat, lacrimal (tear) glands, & small skeletal muscles that move the eyes.

Vertebral Column / Spinal column / Spine

Consists of 26 irregular shaped bones (vertebrae) that are joined & supported by ligaments and trunk muscles in such a way that a flexible, curved structure results. The major supporting ligaments are the anterior & posterior longitudinal ligaments that run vertically along the anterior & posterior surfaces of the vertebral column.

Quadriceps femoris muscle group

Consists of four muscles that form most of the bulk of the front and sides of the thigh. All the muscles of this group have a common tendon that extends to the patella, and then from the patella, the patellar ligament extends to the tibial tuberosity. Specific members of the quadriceps femoris muscle group: rectus femoris vastus lateralis vastus medialis

Hamstring muscle group

Consists of three muscles that form the bulk of the posterior thigh. Straining ("pulled") is a common sports injury in very hard-running athletes. Specific members: biceps femoris semitendinosus semimembranosus

Bony Pelvis

Consists of: 2 Hip bones + Sacrum + Coccyx 2. Divided into the (a) false / greater pelvis and the (b) true / lesser pelvis, which are separated by a ridge called the pelvic brim.

Skull

Cranial bones (which enclose & protect brain) + Facial bones (are responsible for the overall shape of the face).

Sarcoplasm

Cytoplasm of muscle cells/fibers

A bands

Dark bands correspond to the portions of sarcomeres where both the entire length of the thick filaments and the inner portions of the thin filaments are present. involve some overlapping of thin & thick filaments;

Pelvic Girdle

Each hip bone unites with its partner anteriorly and with the sacrum posteriorly. b. Three Major Portions/Regions of Hip Bone: Ilium, Pubis, & Ischium

inervation for all muscles of facial expression:

Facial nerve (Cranial nerve VII). Bell's palsy is paralysis of facial muscles associated with dysfunction of the facial nerve.

Rib Pairs 11-12

False ribs that are even more specifically designated as "Floating" ribs because they have no costal cartilages and have no attachment to the sternum at all.

Rib Pairs 8-10

False ribs whose costal cartilages do not extend all the way to the sternum, but rather join the cartilages associated with more superior ribs, so they have only indirect attachment to the sternum.

Lacrimal bones

Fingernail-size bones that form a small part of the medial wall of each orbit (eye socket). Each has a groove that provides for passage of tears from the orbit to the nasal cavity.

Ilium

Flaring, largest, & superior portion of hip bone. Articulates with the sacrum to form the sacroiliac joint. Has a superior ridge called the iliac crest. Has a deep indentation on its posterior edge called the greater sciatic notch, through which the sciatic nerve courses to the posterior thigh.

Temporal bones

Form inferolateral (inferior-lateral) walls of cranium. Meet the parietal bones at the squamous suture. Specific parts (Bone markings): external auditory meatus Zygomatic process mastoid process mandibular fosa carotid canal

Parietal bones

Form most of the superior & lateral walls of the skull. The two parietal bones meet one another at the sagittal suture and meet the frontal bone at the coronal suture.

Palatine bones

Form the posterior part (but only a small portion of) the hard palate. ** Cleft palate results when the palatine bones and/or palatine processes of the maxilla fail to fuse medially during fetal development. This defect leaves an opening between the oral & nasal cavities that interferes with the baby's ability to nurse.

Frontal bone

Forms forehead. Contains frontal sinuses, which are "paranasal" sinuses. Supraorbital margin of Frontal bone = ridge at superior aspect of eye socket (orbit)

Sphenoid bone

Forms part of orbit of eye (eye socket), some of the floor of the skull, and a little of the lateral portion of the skull. b. Specific parts (1) Sphenoid sinuses (are "paranasal" sinuses). (2) Hypophyseal fossa of Sella turcica -- small depression on superior aspect of sphenoid bone in which the pituitary gland is located. (3) Optic foramen (or Optic canal) -- allows passage of optic nerve from eye to brain.

Occipital bone

Forms posterior part of the skull and most of its base. Meets parietal bones at the lambdoid suture. Specific parts: Occipital condyles Magnum foramen

Vomer bone

Forms the inferior portion of the nasal septum.

Projections that help form joints

Head -- generally, a rounded projection. Condyle -- generally, a wheel-shaped or rounded projection

Some "types" of synovial joints classified by shapes of articulating surfaces:

Hinge joint Pivot joint Ball-and-socket joint

Muscles That Move the Thigh (Femur) and/or Leg (Tibia)

Iliopsoas Sartorius Quadriceps femoris muscle group Tensor fasciae latae gracilis adductor musle group gluteus medius gluteus maximus hamstring muscle group

Sutures

Immovable joints

Muscles of Pelvic Floor

Include the pelvic diaphragm and urogenital diaphragm, both of which are sheets of muscles in the pelvic floor that support pelvic organs such as the uterus & urinary bladder

Skin

Insertion for all muscles of facial expression

Sternum

Is a flat bone to which 10 out of the 12 pairs of ribs attach to via costal cartilages. Parts of sternum: Manubrium, Body, & Xiphoid process (1) Manubrium -- superior portion; medial end of clavicles articulate with it (a) Suprasternal/Jugular notch -- small indentation on superior border of manubrium (2) Body -- middle & largest portion of sternum

Mandible

Is the lower jawbone. Specific parts of Mandible Mandibular condyle / Head of mandible Alveolar margin Body Rami (singular = Ramus) Mandibular foramen

Clavicle (Collarbone)

Its sternal end articulates medially with the sternum's manubrium, whereas its acromial end articulates laterally with the scapula's acromion. It acts as a brace to hold the shoulder in its lateral position -- if the clavicle is broken, the shoulder caves in medially.

Muscles that Move the Mandible (Lower Jaw)

Masseter temporalis provide for mastication/chewing

Adductor muscle group

Muscle group essentially located in the medial thigh ** All the muscles in this group insert on the femur, adduct the thigh, and are used to press the thighs together ** Strain of this muscle group is called a "pulled groin". ** Specific members of this group include the (1) adductor longus and (2) adductor magnus.

Muscles are generally arranged ??

Muscles are generally arranged on opposite sides of a joint such that whatever movement(s) can be produced by muscles on one side of the joint can be reversed by muscles on the opposite side of the joint. So, in general, groups of muscles that produce opposite movements lie on opposite sides of a given joint.

pull

Muscles?? when they attach to their origins & insertions via strong fibrous connective tissue that is arranged in the form of tendons or aponeuroses. ; during contraction, the insertion is pulled on & moved toward the origin (and generally toward where the bulk of the muscle is located).

Skeletal Muscle Disorders

Myasthenia gravis

Hyoid bone

Not really part of skull -- is located in the anterior neck about 1 inch above the larynx. Only bone in body that does not directly articulate with another bone. Serves as an attachment site for muscles associated with swallowing.

Most of the muscles that move the hand are located in

the forearm and have long tendons that extend to the hand, primarily allowing them to flex & extend the wrist & fingers. At the wrist, the tendons of these muscles are held in place by "bands" of fascia (connective tissue) called retinacula (singular = retinaculum). There's an anterior flexor retinaculum (transverse carpal ligament) on the front of the wrist and a posterior extensor retinaculum on the back of the wrist. Long tendons extend from the forearm to manipulate the fingers similar to the way a puppeteer controls the movements of a puppet with long strings. However, small muscles do occur in the hand itself, where they provide for extremely precise finger movements

T tubules

the impulse is conveyed from the sarcolemma surface to deep inside the muscle fiber and the sarcoplasmic reticulum. Upon being stimulated by the impulse, the sarcoplasmic reticulum releases calcium ions that allow myosin cross bridges to attach to thin/actin filaments, thus contraction of the skeletal muscle cell begins.

Two fibrocartilage articular discs / menisci occur in the knee joint cavity

the lateral meniscus (which rests on the tibia's lateral condyle) medial meniscus (which is located on top of the tibia's medial condyle). These menisci provide only a modest stabilizing-effect for the knee joint. (The main stabilizing factor for the knee joint is the tone/tension in the skeletal muscles and tendons that surround it.)

Tibia

the more medial and far larger of the two bones in the anatomical leg (the other leg bone being the fibula). The proximal end articulates with condyles on the distal femur to help form the knee joint, whereas the distal end articulates with the talus (a tarsal bone) to help form the ankle joint.

Two specific carpal bones directly articulate with the radius

the scaphoid & lunate bones. The scaphoid is the most frequently fractured wrist bone, which often results from falling on an outstretched hand.

Although everyone's skeletal muscles contain mixtures of

the three fiber types, some people have relatively more of one type or another. These differences are genetically determined and have an influence on the athletic capabilities of endurance versus strength.

swallowing begins when???

the tongue & buccinator muscles squeeze food posteriorly through the mouth toward the pharynx. Then, groups of muscles in the throat/pharynx contract in the sequence indicated below to complete the swallowing process.

Arthritis

there are several different kinds, but they all have the same initial symptoms: pain & stiffness. Chronic (slow developing, long-lasting) forms of arthritis include osteoarthritis & rheumatoid arthritis.

myosin filaments

thick filaments located in the central portion of a sarcomere. The thick filaments bear tiny knobs called cross bridges/? heads.

olfactory foramina

tiny holes in cribriform plate that allow passage of olfactory nerve fibers that convey impulses for the sense of smell from the top of the nasal cavity toward the brain. ethmoid

Sacrum

triangular shaped bone that consists of five fused vertebrae; articulates laterally with the ilium of each hip bone to form the sacroiliac joints; the sacral promontory on the anterior, superior margin of the sacrum can hinder delivery

Eversion

turning the sole of the foot so that its faces laterally.

transverse processes

two projections that extend laterally from the vertebral arch

Epicranius

two-part muscle consisting of a frontal belly & an occipital belly connected by an aponeurosis (the cranial aponeurosis) which covers the superior part of the skull. Frontal belly of epicranius and occipital belly of epicranius

Rami (singular = Ramus) of mandible

vertical portions of mandible

glenoid cavity/fossa

very shallow socket with which the head of the humerus articulates, forming the essence of the shoulder joint. shallow, and ligaments do not tightly bind the scapula & humerus to one another, the shoulder joint has a great deal of mobility, but on the down-side, the shoulder joint is prone to dislocation.

Medial & Lateral condyles of femur

wheel-shaped projections on distal femur that articulate with the relatively flat medial & lateral condyles on the proximal tibia.

H zones

when a sarcomere is relaxed, this area is in the center of A bands contain only thick filaments.

Pectoralis minor

a. Location: Lies deep to pectoralis major in upper chest b. Insertion: Scapula c. Action: Protracts (pulls forward) the shoulder, specifically the scapula

Smooth muscle tissue

. Located in the walls of hollow internal organs such as the stomach, intestines, urinary bladder, uterus, respiratory tubes, & blood vessels. b. Often called "visceral" muscle because of its location in several internal organs (viscera). c Its cells have no striations (are non-striated). d. Provides contractions that help propel substances along various tubular organs, such as the small intestine & ureters. (Wave-like contractions called peristalsis push food along the digestive tract and urine through the ureters.) e. Its contractions move food through the digestive tract, empty the bowels & urinary bladder squeeze a baby out of the uterus during delivery, and cause constriction of blood vessels. f. Is involuntary muscle since it cannot be consciously controlled. It contracts under the control of the autonomic nervous system.

I bands

. The light bands in the outer portions of sarcomeres contain only thin/actin filaments

Ethmoid Bone

a. Forms the roof of the nasal cavity & a portion of its lateral walls; forms part of nasal septum. b. Specific parts of Ethmoid bone (1) Ethmoid sinuses (are "paranasal" sunuses). (2) Cribriform plates -- form roof of nasal cavity. (3) Olfactory foramina -- tiny holes in cribriform plate that allow passage of olfactory nerve fibers that convey impulses for the sense of smell from the top of the nasal cavity toward the brain. (4) Crista galli -- small projection that extends upward from between the cribriform plates. (5) Perpendicular plate -- partition of bone that forms the superior part of the nasal septum. [Nasal septum = vertical partition that divides the nasal cavity into left & right halves.] (6) Superior & Middle conchae/turbinates (2 of each) -- project from lateral walls of nasal cavity.

Cardiac muscle tissue

a. Found only in heart, where it composes a thick layer named the myocardium. b. Its cells are striated and arranged in branching chains. c. Its cells contain myofibrils, sarcomeres, & sarcoplasmic reticulum. d. The ends of its cells are joined by intercalated discs in which gap junctions are located. e. Provides the pumping action of the heart which propels blood through the blood vessels. f. Is involuntary muscle since it cannot be consciously controlled. g. The heart has a pacemaker that stimulates its cardiac muscle to contract rhythmically about 75 times a minute (the average resting heartbeat rate). The pacemaker enables the heart to contract/beat without being stimulated by the nervous system. However, the autonomic nervous system can increase or decrease the heart rate to meet changing needs of the body.

Characteristics of skeletal muscle tissue

a. Is packaged in organs called skeletal muscles, which are most often attached to bones via tendons; however, facial muscles are attached to the skin. b. Its cells are multinucleated & striated. c. Its cells contain myofibrils, sarcomeres, & sarcoplasmic reticulum. d. Is voluntary muscle; can be consciously controlled by the somatic motor nervous system

brachialis

a. Lies deep to biceps brachii b. Flexes forearm; synergist of biceps brachii

temporalis

a. Location/Description: Covers parts of temporal & parietal bones; bulging of it can be felt through scalp when teeth are clenched b. Insertion: Mandible c. Action: mastication/chewing; biting; elevates mandible (closes jaw)

Orbicularis oris

a. Location/Description: Encircles & forms core of lips b. Action: Moves lips in a variety of ways, including puckering (pursing & protruding) and closing lips; called the kissing muscle

Buccinator

a. Location/Description: Horizontally orientated cheek muscle b. Action: Compresses cheeks in ways that make blowing, whistling, & sucking possible; holds food between teeth during chewing; well developed in nursing infants

Trapezius

a. Location/Description: Large, superficial muscle in the upper & middle back; upper fibers run inferiorly toward the scapula, middle fibers run horizontally toward the scapula, and lower fibers run superiorly toward the scapula b. Insertion: Scapula c. Action: Elevates (shrugs), depresses, adducts, & retracts scapula & shoulder

Rectus abdominis

a. Location/Description: Most medial & anterior of the muscles described here; runs vertically along the anterior abdomen b. Action: Compresses abdomen, thus increasing intra-abdominal pressure and facilitating urination, defecation, forced expiration, childbirth, & vomiting; flexes trunk & vertebral column; used to do sit-ups

triceps brachii

a. Location/Description: Superficial, lateral forearm; forms lateral border of cubital fossa; extends from distal humerus to distal radius b. Insertion: Styloid process on distal radius c. Action: Flexes forearm; synergist of biceps brachii & brachialis

Splenius muscles

a. Location/Description: Two muscles in posterior neck; lie deep to trapezius b. Insertion: Occipital bone c. Action: Extend & hyperextend head

pronator teres

a. Location: Anterior forearm b. Insertion: Radius c. Action: Pronation (turns forearm & palm backward or downward)

Internal Oblique

a. Location: Anterolateral abdominal wall between external oblique & transversus abdominis; fibers run at an angle b. Action: Same as external oblique

Sternocleidomastoid

a. Location: Anterolateral surface of neck b. Origins: Sternum & Clavicle c. Insertion: Mastoid process of temporal bone d. Action: Simultaneous contraction of both such muscles flexes head & neck; contraction of one alone rotates & tilts head to side e. Clinical info: Spasms of this muscle may cause torticollis/wry neck, a condition in which the neck stays twisted to one side, keeping the head rotated in that direction.

Tensor fasciae latae

a. Location: Anterolateral thigh b. Insertion: Iliotibial tract/band (big, long band of fascia that extends from ilium to tibia)

internal interostals

a. Location: Between ribs b. Action: Elevate ribs, thus increasing the volume of the thoracic & pleural cavities and facilitating inspiration; synergists of diaphragm

external intercostals

a. Location: Between ribs, but run at opposite angle of external intercostals b. Action: Depress ribs during forced expiration (exhalation)

supinator

a. Location: Deep forearm b. Insertion: Radius c. Action: Supination (turns forearm & palm forward or upward)

Transverse Abdominis

a. Location: Deepest of the three anterolateral abdominal muscles; fibers run horizontally b. Action: Compresses abdomen

Gastrocnemius

a. Location: Large, superficial muscle of posterior leg (calf) b. Insertion: Calcaneus via calcaneal/Achilles tendon c. Action: Plantar flexes foot (Plantar flexion)

Gluteus medius

a. Location: Lateral part of butt; common site for intramuscular injections b. Insertion: Lateral femur (specifically, Greater trochanter) c. Action: Abducts thigh

Extensor digitorum longus

a. Location: Lateral to tibialis anterior b. Action: Extends all toes, except big toe (hallux)

Soleus

a. Location: Lies deep to gastrocnemius b. Insertion: Calcaneus via calcaneal/Achilles tendon c. Action: Plantar flexes foot (Plantar flexion)


Kaugnay na mga set ng pag-aaral

death and immortality rn106 exam 1

View Set

Chapter 5/6 Economics Exam Questions

View Set

Accident & Health Insurance Policies

View Set