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182 Cards in this Set

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What composes the SKELETAL SYSTEM?
All the bones of the body plus the joints formed by their attachments to each other
What are the main categories of SKELETAL BONES and how many bones comprise them (approximately)
Axial 80
Appendicular 126
name ##
name ###
What are the FUNCTIONS of the SKELETAL SYSTEM?
1. Protection
2. Support
3. Movement
4. Mineral Reservoir
5. Hemopoiesis
6. Energy storage
Six
What is the HISTOLOGY of the BONES OF THE SKELETAL SYSTEM?
Haversian Systems (osteons)
a. osteocytes
b. lamella
c. lacunae
d. canaliculi
e. Haversian canal

4 Different Kinds Of Cells
a. Osteoprogenitor Cells (mesenchyme)
b. Osteoblasts
c. Osteocytes
d. Osteoclasts
type a-e
type a-d
How are bones classified and what are the types?
According to space in between elements
1. spongy (cancellous)
2. compact
two types
What are the features of the TYPICAL LONG BONE?
1. Epiphyseal plate
2. Diaphysis
3. Epiphysis
4. Articular Cartilage
5. Periosteum
6. Endosteum
7. Medullary cavity
8. Red bone marrow
9. Yellow bone marrow
9 features
Define Medullary Cavity
The space within a bone that contains the marrow.
Bone MATRIX COMPOSITION:
Organic Framework (33%)
(collagen fibers/ground substance)

Inorganic salts (67%)
(calcium/phosphate salts)
2 main types (%)
(ingredients)
Name the types of BONE OSSIFICATION
Intramembranous and Endochondral
2 types
Where does INTRAMEMBRANOUS OSSIFICATION occur?
1. flat skull bones
2. mandible
3. part of clavicle
3 places
Where does ENDOCHONDRAL OSSIFICATION occur?
In all bones (including long bones, etc) except the flat skull bones, the mandible, and part of the clavicle
not intramembranous
Embrionically, All bones form from what?
the middle layer of embryonic cells called mesoderm
middle layer
What is another name for INTRAMEMBRANOUS OSSIFICATION?
Dermal Ossification
What is another name for ENDOCHONDRAL OSSIFICATION?
Intracartilaginous Ossification
What are the steps of INTRAMEMBRANOUS OSSIFICATION?
1. Mesenchyme cells differentiate into osteoblasts and start to secrete matrix
2. Osteoblasts form spicules of matrix
3. Spicules trap osteoblasts in lacuna
4. Activity slows
5. Trapped osteoblasts called osteocytes
6. Bone growth proceeds outward from center (ossification center)
7. Spicules thicken into trabeculae (spongy bone)
8. Trabeculae connect (compact bone)
eight steps
Where does INTRAMEMBRANOUS OSSIFICATION begin, what is the beginning point called, and in what direction does it proceed?
In the center of the bone, or the PRIMARY OSSIFICATION CENTER, and it proceeds outward.
What does SPICULES mean?
little skinny sticks
What are the steps of ENDOCHONDRAL OSSIFICATION?
1. Mesenchyme cells form cartilage model. 2. Perichondrium surrounds cartilage model. 3. Osteoblasts differentiate on inner surface of perichondrium. 4. Collar of compact bone surrounds cartilage of diaphysis bone. 5. Chondrocytes and lacunae in diaphysis enlarge (reducing amount of matrix). 6. Calcium deposits in remaining matrix (calcified cartilage). 7. Nutrients can't diffuse. 8. Chondrocytes die leaving hollow spaces. 9. Blood vessels and osteoprogenitor cells enter matrix from periosteum. 10. Osteoprogenitor cells differentiate into osteoblasts. 11. Osteoblasts form trabeculae/bone matrix. 12. This forms PRIMARY OSSIFICATION CENTER in diaphysis. 13. Later SECONDARY OSSIFICATION CENTERS form in epiphyses
13 steps
How do long bones increase in length?
By laying down new bone at epiphyseal plate
At side of epiphyseal plate toward epiphysis cartilage cells:
lay down new cartilage
At the side of the epiphyseal plate toward the diaphysis, cartilage is:
being replaced by bone
ENDOCHONDRAL OSSIFICATION starts when?
6-8 weeks of development
embryological
INTRAMEMBRANOUS OSSIFICATION starts when?
8 weeks of development
embryological
Long bones increase in DIAMETER by:
1. Osteoblasts laying down new bone from periosteum
2. Osteoclasts reabsorbing bone from the endosteum
two steps
Bone classification by SHAPE:
1. Long
2. Short
3. Flat
4. Irregular
Four types
Two other types of bone (other than shape types)
sesamoid and sutural (wormian)
What are the GROWTH FACTORS for bone?
Remodeling & Growth
1. Stress (gravitational, functional)
2. Vitamins (A,C,B12, D)
3. Minerals (Ca, P, Na, Mg)
4. Hormones (parathyroid, calcitonin, thyroxine, GH, sex hormones)
Name the PARANASAL SINUSES
Frontal, sphenoid, ethmoid and maxillary
4
PARANASAL SINUSES:
What are they physically?
They are air spaces in certain skull and face bones
PARANASAL SINUSES:
What are they physically in the nasal cavity?
They are a drain in nasal cavity.
PARANASAL SINUSES:
What is their interior histology?
They are lined with ciliated columnar epithelium
What are the functions of PARANASAL SINUSES?
1. Lighten skull
2. Warm air
3. Resonate Sound
4. Protection
5. Produce Mucus
five
What are FONTANELS?
Large membranous areas between incompletely ossified skull bones.
What do FONTANELS do?
They allow for flexibility and skull growth.
Name the FONTANELS:
1. Anterior
2. Posterior
3. Sphenoid
4. Mastoid
four
How many ANTERIOR FONTANELs do we have and what bones comprise it/them?
We have ONE, and it is a meeting of the FRONTAL and PARIETAL bones.
How many POSTERIOR FONTANELs do we have and what bones comprise it/them?
We have ONE, and it is a meeting of the OCCIPITAL and PARIETAL bones.
How many SPHENOID FONTANELs do we have and what bones comprise it/them?
We have TWO, and they are a meeting of the TEMPORAL, FRONTAL, PARIETAL and SPHENOID bones.
How many MASTOID FONTANELs do we have and what bones comprise it/them?
We have TWO, and they are a meeting of the PARIETAL, OCCIPITAL and TEMPORAL bones.
Name the primary curves of the vertebral column:
Posterior thoracic curve
Posterior sacral curve
Name the secondary curves of the vertebral column:
Anterior cervical curve
Anterior lumbar curve
When do the PRIMARY CURVES OF THE VERTEBRAL COLUMN develop?
They are present at birth
When do the SECONDARY CURVES OF THE VERTEBRAL COLUMN develop?
They develop after birth
Skeletal Differences in males and females:
GENERAL SKELETON
Male: heavier/thicker

Female: lighter/thinner
Skeletal Differences in males and females:
PELVIC INLET
Male: heart shaped

Female: round
Skeletal Differences in males and females:
OBTURATOR FORAMEN
Male: oval

Female: triangular
Skeletal Differences in males and females:
ACETABULUM
Male: faces laterally

Female: faces anteriorly
Skeletal Differences in males and females:
PUBIC ARCH
Male: acute

Female: obtuse
Skeletal Differences in males and females:
SACRUM
Male: curved anteriorly

Female: less curved
Skeletal Differences in males and females:
COCCYX
Male: close to symphysis

Female: not close
Skeletal Differences in males and females:
FOREHEAD
Male: steep/flat

Female: rounded
Skeletal Differences in males and females:
ORBITS
Male: square

Female: rounded
Skeletal Differences in males and females:
PALATE
Male: broad

Female: narrow
Skeletal Differences in males and females:
MANDIBLE
Male: large/square

Female: small, pointed
Name the types of FRACTURES
1. Colles' 2. Compression 3. Comminuted 4. Displaced 5. Epiphyseal 6. Greenstick 7. Nondisplaced 8. Pott's 9. Spiral 10. Stress 11. Transverse
eleven
Define:

POTT'S FRACTURE
Occurs at the ankle and affects both the tibia and the fibula.
Define:

COMMINUTED FRACTURE
Shatter the affected area into a multitude of bony fragments.
Define:

TRANSVERSE FRACTURE
Break a bone across it's long axis.
Define:

SPIRAL FRACTURE
Produced by twisting stresses that spread along the length of the bone.
Define:

DISPLACED FRACTURE
Produce new and abnormal bone arrangements.
Define:

NONDISPLACED FRACTURE
Retain the normal alignment of the bones or fragments.
Define:

COLLES' FRACTURE
A break in the distal portion of the radius. Typically the result of reaching out to cushion a fall.
Define:

GREENSTICK FRACTURE
Only one side of the shaft is broken, and the other is bent. This type of fracture generally occurs in children, whose long bones have yet to fully ossify.
Define:

EPIPHYSEAL FRACTURE
Tend to occur where the bone matrix is underegoing calcification and chondrocytes are dying. A clean transverse fracture along this line generally heals well. Unless carefully treated, fractures between the epiphysis and the epiphyseal cartilage can permanently stop growth at the site.
Define:

COMPRESSION FRACTURE
Occur in vertebrae subjected to extreme stresses, as when you land on your seat in a fall. They are more common when bones are weakened by osteoporosis.
Define:

STRESS FRACTURE
A fracture caused by repetitive stress, as may occur in sports, strenuous exercise, or heavy physical labor. Osteoporosis increases the possibility of stress fractures.
Name the two divisions of the Skeleton and the number of bones in each
Axial (80)
Appendicular (126)
The SKULL contains how many bones?
29
The CRANIUM contains how many bones?
8
The FACE, EARS AND HYOID comprise how many bones?
21
Name the bones of the CRANIUM
Frontal, Ethmoid, Sphenoid, Occipital, Parietal (2), Temporal (2)
8
Name the bones of the FACE, EARS AND HYOID
Vomer, Mandible, Maxillary (2), Zygomatic (2), Nasal (2), Lacrimal (2), Inferior Nasal Conchae (2), Palatine (2), Malleus (2), Incus (2), Stapes (2), Hyoid
21
How many bones of the VERTEBRA do we have?
26
How many CERVICAL VERTEBRA do we have?
7: the atlas, the axis + 5
How many THORACIC VERTEBRA do we have?
12
How many LUMBAR VERTEBRA do we have?
5
How many SACRUM do we have?
1 consisting of 5 fused vertebra
How many COCCYX do we have?
1 consisting of 3-4 fused vertebra
How many RIBS do we have?
24
What are the categories of ribs and what are their numbers?
True (1-7), False (8,9,10), and Floating (11,12)
What bones comprise the STERNUM?
The MANUBRIUM, the BODY, and the ZIPHOID PROCESS
How many bones are in the APPENDICULAR SKELETON?
126
What bones comprise the PECTORAL GIRDLE, and how many of each are there?
The SCAPULA (2) and the CLAVICLE (2)
4
How many bones are in the ARMS and HANDS?
60
What bones comprise the ARMS and HANDS, and how many of each are there?
HUMERUS (2), RADIUS (2), ULNA (2), CARPALS (16), METACARPALS (10), PHALANGES (28)
60
What bones comprise the PELVIC GIRDLE and how many of each are there?
COXAL BONES (2) consisting of the fused ilia, ischia, and pubic bones
fused
How many bones comprise the LEGS and FEET?
60
What are the bones of the LEGS and FEET, and how many of each are there?
FEMUR (2), TIBIA (2), FIBULA (2), PATELLA (2), TARSALS (14), METATARSALS (10), PHALANGES (28)
Name common disorders of the SKELETAL SYSTEM
1. Kyphosis
2. Loordosis
3. Scoliosis
4. Osteoporosis
5. Osteomalacia
6. Osteomyelitis
7. Fractures
7
Define KYPHOSIS
Abnormal exaggeration of the thoracic curvature that produces a "roundback" appearance.
Define LORDOSIS
Abnormal lumbar curvature giving a "swayback" appearance.
Define SCOLIOSIS
Abnormal lateral curvature of the spine.
Define OSTEOPOROSIS
A reduction in bone mass and strength sufficient to compromise normal bone function.
Define OSTEOMALACIA
A softening of bone due to a decrease in the mineral content.
Define OSTEOMYELITIS
A painful infection in a bone, usually caused by bacteria.
Define FRACTURES
A break or crack in a bone.
Define ARTICULATIONS
Joints between bones
How are ARTICULATIONS classified?
Both STRUCTURALLY and FUNCTIONALLY.
2
How are ARTICULATIONS classified STRUCTURALLY?
According to the material between bones at the articulation
What are the STRUCTURAL classifications of articulations and what is the material between the bones in each?
1. Fibrous joints (fibrous connective tissue)
2. cartilagenous joints (cartilage)
3. synovial joints (synovial fluid)
3
How are ARTICULATIONS classified FUNCTIONALLY?
According to the movement permitted at the articulation.
What are the FUNCTIONAL classifications of articulations and what is the movement allowed in each?
1. Synarthroses (no movement)
2. Amphiarthroses (slight movement)
3. Diarthroses (freely moveable)
3
Name the types of FIBROUS JOINTS
1. Sutures
2. Syndesmoses
3. Gomphoses
3
Define the FIBROUS JOINT:
SUTURES
Give example(s)
short, SUTURAL LIGAMENTS
held tight
SYNARTHROSES
ie: between flat skull bones
Define SYNOSTOSIS
When two separate bones fuse together, and the boundary between them disappears. This creates a totally rigid, immovable joint (BONY FUSION)
Define the FIBROUS JOINT:
SYNDESMOSES
Give example(s)
longer, INTEROSSEOUS LIGAMENTS
give
AMPHIARTHROSES
ie: between distal tibia & fibula
between middle radius and ulna
Define the FIBROUS JOINT:
GOMPHOSES
Give example(s)
PERIDONTAL LIGAMENT
no movement
SYNARTHROSES
ie: between teeth and sockes in jaw
Name the types of CARTILAGENOUS JOINTS
1. Synchondroses
2. Symphyses
What is the material between bones in FIBROUS JOINTS?
fibrous connective tissue
What is the material between bones in CARTILAGENOUS JOINTS?
cartilage
What is the material between bones in SYNOVIAL JOINTS?
synovial fluid
Define the CARTILAGENOUS JOINT:
SYNCHONDROSES
Give example(s)
HYALINE CARTILAGE
2 kinds: temporary (epiphyseal plate)& permanent (costal cartilage)
SYNARTHROSES (or AMPHIARTHROSES)
ie: epiphysial plate (temp)
ribs/sternum (perm)
Define the CARTILAGENOUS JOINT:
SYMPHYSES
Give example(s)
FIBROCARTILAGE
AMPHIARTHROSES
ie: pubic symphysis
What is the FUNCTIONAL CLASSIFICATION of all SYNOVIAL joints?
DIARTHROSES / freely moveable
What are the prominent features of all SYNOVIAL JOINTS?
1. hyaline articular cartilage on bone surface
2. articulating surfaces separated by a joint cavity
3. cavity enclosed by fibrous capsule
4. synovial membrane lines cavity
5. membrane secretes synovial fluid into cavity
note: synovial membrane does not cover articular cartilage -- just where articular cartilage is not present
What are the functions of SYNOVIAL FLUID?
1. lubricates
2. nourishes
3. cushions / shock absorber
3
Define the SYNOVIAL JOINT:
BALL and SOCKET
Give akas, movement, example(s)
aka SPHEROID, COTYLOID
round head on one fits into concave socket on other
greatest degree of movement
TRIAXIAL
ie: Hip, Shoulder
Define the SYNOVIAL JOINT:
CONDYLOID
Give akas, movement, example(s)
aka ELLIPSOIDAL
shallow socket
one surface slightly concave/one surface slightly convex
BIAXIAL
ie: Metacarpals/phalanges (knuckles)
Radius-ulna/carpals
Define the SYNOVIAL JOINT:
SADDLE
Give akas, movement, example(s)
aka SELLAR
two opposed curved surfaces (2 saddles)
BIAXIAL
ie: trapezium/metacarpal of thumb (only)
Define the SYNOVIAL JOINT:
HINGE
Give akas, movement, example(s)
aka GINGLYMUS
convex surface of one bone fits concave surface of other
UNIAXIAL
ie: Elbow, Knee, Interphalangeal
Define the SYNOVIAL JOINT:
PIVOT
Give akas, movement, example(s)
aka TROCHOID
central bony pivot surrounded by collar of bone
allows rotation around a longitudinal axis
UNIAXIAL
ie: Atlas/Axis
Head radius/ulna (proximal)
Define the SYNOVIAL JOINT:
GLIDING
Give akas, movement, example(s)
aka PLANE, ARTHRODIA
limited sliding between two almost flat surfaces
NONAXIAL
ie: Articular processes of vertebrae
Between most carpals/tarsals
What are some common DISORDERS OF JOINTS?
1. Osteoarthritis
2. Rheumatoid Arthritis
3. Gouty Arthritis
4. Dislocation
5. Sprain
6. Strain
7. Bursitis
7
Define Joint Disorder:
OSTEOARTHRITIS
Articular cartilage degenerates
Affects 85% of people over 70
Joints less mobile, enlarged, painful
Define Joint Disorder:
RHEUMATOID ARTHRITIS
Any age
Chronic / Acute
Joints become deformed, inflammed, immovable, impaired function
Autoimmune disease
Define Joint Disorder:
GOUTY ARTHRITIS
aka GOUT
Genetic
Excessive amounts of blood uric acid
Deposits in kidneys and joints
Define Joint Disorder:
DISLOCATION
bones moved out of articulation
Define Joint Disorder:
SPRAIN
damage to the ligaments or tendons at a joint
Define Joint Disorder:
STRAIN
tear or break in a muscle
Define Joint Disorder:
BURSITIS
inflammation of a bursa
How many muscles are in the body?
Approximately 600
MUSCULAR SYSTEM: Notable features
Approximately 600 muscles in body
Nearly half the body by weight
Chemical energy of nutrients is converted to mechanical energy in muscles (contraction)
What are the PROPERTIES OF MUSCLES?
CONTRACTILITY - ability to shorten
EXCITABILITY - ability to respond to a stimulus
EXTENSIBILITY - ability to stretch or extend
ELASTICITY - if you stretch muscle it will return to normal length
4
Functions of muscle (contractions):
1. Movement
2. Posture/Support
3. Heat production
3
Name the TYPES OF MUSCLES, where they are found, and their control
1. SKELETAL, attached to bones, voluntary
2. SMOOTH, in walls of hollow viscera, involuntary
3. CARDIAC, heart, involuntary
3
What are notable features of SKELETAL MUSCLE?
1. muscle cell = muscle fiber
2. very little matrix in muscle tissue
3. fibers extend full length of muscle
4. each fiber innervated by 1 axon ending (of motor neuron)
5. a single motor axon may innervate 10-200 muscle fibers
6. multinucleate (many nuclei per cell)
7. 30-40 cm (10-16 in) long
Define:
MOTOR UNIT
(in muscle)
One MOTOR NEURON + all the MUSCLE FIBERS it innervates
What are the connective tissue components of muscle, where are they found, and what is their histology?
Fascia
1. ENDOMYSIUM, around cell membrane of fiber, areolar connective tissue
2. PERIMYSIUM, around bundles of fibers (fasciculi), dense irregular connective tissue
3. EPIMYSIUM, around whole muscle, dense irregular connective tissue
Define:
FASCIA
Connective tissue fibers, primarily collagenous, that form sheets or bands beneath the skin to attach, stabilize, enclose and separate muscles and other internal organs.
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

muscle fiber =
cell
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

Cytoplasm =
sarcoplasm
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

cell membrane =
sarcolemma
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

sarcoplasm contains ...
100s - 1000s of cylindrical MYOFIBRILS
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

MYOFIBRILS are made up of ...
2 types of MYOFILAMENTS
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

MYOFILAMENTS
THIN filaments (actin)
THICK filaments (myosin)
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

Define SARCOMERE
myofilaments arranged in repeating functional units
RE: MICROSCOPIC STRUCTURE OF MUSCLE FIBER

What causes the banding appearance (cross striations)?
arrangement of myofilaments
Sliding Filament Mechanism
1. Tendon
2. Aponeurosis
3. Origin/Insertion/Action
4. Agonist (prime movers) / Antagonist / Synergist
MUSCLE:
What determines range of MOVEMENT and POWER?
ARCHITECTURE of muscles (how fascicles are grouped)
Name the ARRANGEMENT OF FASCICULI
1. Parallel
2. Pennate
3. Convergent
4. Circular
4
Arrangement of Fasciculi:
PARALLEL
aka LONGITUDINAL
fasciculi parallel to long axis of muscle
flat bands (straps) or spindle
most skeletal muscles in body
produce much movement/ little power
ie: sartorius, rectus abdominus
pbsm
Arrangement of Fasciculi:
PENNATE
have tendons running entire length of muscle
fasciculi short
insert obliquely on tendon
produce little movement/great power
UNIPENNATE, BIPENNATE, MULTIPENNATE
tsom
Arrangement of Fasciculi:
CONVERGENT
radiate
fasciculi converge from a broad origin into a single narrow tendon
can change direction of pull
less powerful than parallel
ie: pectoralis major
Arrangement of Fasciculi:
CIRCULAR
fasciculi arranged in circular pattern
close opening
ie: orbicularis oculi
Define UNIPENNATE
ie:
all fasciculi insert on one side of tendon
ie: tibialis anterior
Define BIPENNATE
ie:
fasciculi insert obliquely on both side of tendon
ie: rectus femoris
Define MULTIPENNATE
ie:
fasciculi attach obliquely along many tendons
ie: deltoid
Criteria used naming of muscles
ACTION (flexor carpi ulnaris)
DIRECTION OF FIBERS (rectus abdominis)
LOCATION (tibialis anterior)
NUMBER OF DIVISION (triceps brachii)
SHAPE (trapezius)
POINTS OF ATTACHMENT (sternocleidomastoid)
SIZE (gluteus maximus)
7
Name the Angular Movements
1. Flexion
2. Extension
3. Adduction
4. Abduction
5. Circumduction
6. Rotation
7. Supination
8. Pronation
8
Angular Movements
Define:
FLEXION
a movement in the anterior-posterior plane that reduces the angle between the articulating elements
ie: bending the wrist forward
Angular Movements
Define:
EXTENSION
movement in the anterior plane that increases the angle between articulating elements
ie: bending the wrist backwards
Angular Movements
Define:
ADDUCTION
a returning movement toward the longitudinal axis of the body (the opposite of abduction)
ie: moving the arm back in toward the body after an outward swing
Angular Movements
Define:
ABDUCTION
movement away from the longitudinal axis of the body in the frontal plane.
ie: moving the arm away from the body
Angular Movements
Define:
CIRCUMDUCTION
moving your arm in a loop
ie: when drawing a large circle on a chalkboard
Angular Movements
Define:
ROTATION
left and right rotation of the head produce a "NO"
Angular Movements
Define:
SUPINATION
movement that turns the palm forward
Angular Movements
Define:
PRONATION
movement that turns the palm facing back
Name the SPECIAL MOVEMENTS
1. Elevation
2. Depression
3. Inversion
4. Eversion
5. Protraction
6. Retraction
Special Movements
Define:
ELEVATION
occurs when a structure moves in a superior direction.
ie: you elevate our mandible when you close your mouth
Special Movements
Define:
DEPRESSION
occurs when a structure moves in an inferior direction.
ie: you depress your mandible when you open your mouth
Special Movements
Define:
INVERSION
a twisting motion of the foot that turns the sole inward
Special Movements
Define:
EVERSION
a twisting motion of the foot that turns the sole outward
Special Movements
Define:
PROTRACTION
moving a part of the body anteriorly in the horizontal plane
ie: you protract our jaw when you grasp your upper lip with your lower teeth.
Special Movements
Define:
RETRACTION
Moving a part of the body posteriorly in the horizontal plane
ie: when you pull your chin back in after sticking it out.
Notable for Smooth Muscle
spindle shaped fiber
small (.01-.05 mm)
one nucleus per cell
myofilaments random
usually arranged in 2 layers
- inner...circular
- outer...longitudinal
2 types of smooth muscle
Name the two types of SMOOTH MUSCLE
Visceral (Single Unit) and Multiunit
Smooth Muscle:
VISCERAL (Single Unit)
Contraction initiated by...
local tissue factors and hormones
Smooth Muscle:
VISCERAL (Single Unit)
Location:
wall of small blood vessels
wall of gut
wall of uterus
wall of ureters and urinary bladder
Smooth Muscle:
MULTIUNIT
Contraction due to...
innervation by motor nerve
Smooth Muscle:
MULTIUNIT
Location:
wall of large arteries
wall of large airways
iris (radial/circular)
arrector pili muscles
Notable re: Cardiac Muscle
Striated microscopic appearance
One nucleus per cell
Thickenings at cell membrane junctions (intercalated discs)
Wall of heart
Fibers arranged in 2 branching networks
Stimulation via SPECIALIZED excitation/conductive cardiac muscle fibers.
Name and Define Common Disorders of the MUSCLE SYSTEM
Myasthenia Gravis (abnormal neuromuscular junction, weak)
Muscular Dystrophy (degenerationof fibers, atrophy)