origin: pubis

insertion: tibia

action: abduction, flexion, lateral rotation

origin: pubis

insertion: tibia

action: flexion, medial rotation (hip + knee) adduction/ hip

origin: illium

insertion: iliotibial tract

action: abduction, medial rotation or hip, extension, lateral rotation 

origin: illium

insertion: tibia, patella

action: extension at knee, flexion at hip

origin: femur

insertion: tibia, patella

action: extension at knee

origin: femur

insertion: tibia, patella

action: extension at knee

origin: femur

insertion: tibia, patella

action: extension at knee

origin: femur, iscium

insertion: fibia, tibia

action: flexion at knee, extension, lateral rotation at hip

origin: ischium

insertion: tibia

action: flexion at knee, extension, medial rotation of hip

origin: ischium

insertion: tibia

action: flexion at knee, extension, medial rotation of hip

origin: illium, sacrum, coccyx

insertion: femur, it tract

action: extension, lateral rotation, abduction of hip

origin: illium

insertion: femur

action: adduction, medial rotation of hip

origin: femur

insertion: calcaneus

action: plantar flexion at ankle, flexion at knee

origin: fibia, tibia

insertion: calcaneus

action: plantar flexion

origin: tibia

insertion: metatarsal (1st medial cuneiform)

action: dorsiflexion

origin: scapula

insertion: radius

action: flexion at elbow, shoulder spination

origin: occipital bone, thoracic vertebrae

insertion: clavicle, scapula

action: elevate, retract, depresses scapula and clavicle

origin: clavicle, scapula

insertion: humerous

action: abduction (shoulder), flexion, medial rotation, extension, lateral rotation of humerous

origin: thoracic, lumbar, sacral vertebrae, ribs

insertion: humerous

action: extension, adduction, medial rotation of shoulder

origin: cervicle vertebrae

insertion: scapula

action: elevate scapula

origin: scapula

insertion: humerous

action: abduction of shoulder

origin: scapula

insertion: humerous

action: lateral and medial rotation of shoulder

origin: scapula

insertion: humerous

action: extension, medial rotation of shoulder

origin: scapula

insertion: humerous

action: lateral rotation, adduction of shoulder

origin: vertebrae

insertion: scapula

action: abduction/downward rotation of scapula

origin:thoraculumbar fascia, inguinal ligament, and iliac crest

insertion: ribs 2

action:compresses abdomen, depresses ribs, rotates vertebral column to same side

origin: ribs

insertion: linea alba and illiac crest

actionaction:compresses abdomen, depresses ribs, rotates vertebral column to opposite side

origin: ribs, illiac crest, and thoracolumbular fascia

insertion: linea alba and pubis

action: compresses abdomen

origin: pubis (pubic symphysis)

insertion: inferior surfaces of cartilages (ribs 5-7) and xiphod process of the sternum

action: depresses ribs, flexes vertebral column, and compresses abdomen

origin: ribs, sternum, clavicle

insertion: humerus

action: flexion, adduction, and medial rotation at shoulder

origin: ribs, 

insertion: scapula

action: depresses and protracts shoulder, downward rotation of scapula, elevates ribs

origin: ribs

insertion: scapula

action: protracts, rotates glenoid cavity to move superiorly (upward rotation) 

origin: humerus

insertion: ulna

action: extension at elbow,extension / adduction of shoulder, 

exist wherever 2+ bones meet
maybe in direct contact/seperated by fibrous tissue, cartilage, fluid

varying degrees of motion 

classification of joints by function

synarthrosis

immovable joint

bony edges are close, can even interlock

can be fibrous (suture, gomphosis), cartilaginous (synchondrosis), or bony fusion (synostosis)

synarthroses

suture

synarthrotic joint found only between the bones of the skull

edges of bone are bound together by CT (sutural ligament, sutural membrane)

allows force to spread easily from bone to bone to decrease the chance of injury

synarthroses

gomphosis

specialized form of fibrous synarthrosis that binds each tooth to the surrounding bony socket

fibrous connection: periodontal ligament

synarthroses

synchondroses

ex) epiphyseal cartilage at the end of long bones

cartilaginous attachment 

synarthroses

synostosis

when two separate bones fuse together and the boundary disappears 

ex) when the epiphyseal plate ossifies

amphiarthroses

slightly movable joint

can be: fibrous (syndesmosis) or cartilaginous (symphysis)

bones are usually farther apart then they are in a synarthroses

amphiarthroses

syndesmosis

a ligament connects and limits movement of the articulating bones

ex) distal articulation between the tibia/fibula

interosseus membrane

amphiarthroses

symphysis

bones are separated by a pad or wedge of fibrous cartilage

ex) intervertebral disc, pubic symphysis

diarthroses

synovial 

are specialized for movement

permit a wide range of motions

bony surfaces usually covered by articular cartilage

synovial cavity that contains synovial fluid

synovial

characteristics of synovial joints

1. joint capsule

2. articular cartilage

3. a joint cavity filled with synovial fluid

4. synovial membrane lining the joint capsule

5. accessory structures

6. sensory nerves and blood vessels that supply the exterior and interior of the joint

synovial

articular cartilage

act as shock absorbers and reduce friction

resemble hyaline cartilage in many respects

but they lack a perichondrium and matrix and contain more fluid then hyaline cartilage 

synovial

synovial fluid

synovial membrane secretes/produces the fluid

functions:

1. provides lubrication

2. nourishes the chondrocytes

3. acts as a shock absorber

synovial accessory structures

cartilages and fat pads

lie between opposing articular surfaces and modify the shapes of the joint surfaces

1. Menisci: articular disc, pads of fibrous cartilage that may subdivide a synovial cavity, channel the flow of synovial fluid, allow for variation in shapes of articular surfaces, resist movements at the joint

2. fat pads: provide protection from articular cartilages and serve as packing material for the joint, fat pads fill spaces

synovial accessory structures

ligaments

intrinsic ligaments (capsular ligaments): localized thickening of the joint capsule

extrinsic ligaments: separate from the joint capsule 

synovial accessory structure

tendon

usually pass across or around a joint

provide strength, stability

synovial accessory structure

bursae

small fluid-filled pockets of CT

filled with synovial fluid and lined by a synovial membrane

maybe connected to joint cavity but also can be separate from the joint cavity

reduce friction, absorb shock

synovial tendon sheaths: are tubular bursae that surround tendons that pass across bony surfaces

adventitious bursae: bursae that form in unlikely places

joints cannot be both

greater the range of motion the weaker it becomes

factors that limit mobility and reduce the chance of injury:

1. presence of accessory ligaments and fibers in capsule

2. shapes of articulating surfaces that prevent movement in specific directions

3. presence of other bones, bony processes, skeletal muscles, fat pads 

4. tension in tendons attached to the articulating bones

types of joint movements

linear movement

gliding

ex) pencil remains vertical but tip moves forward, sideways, and diagonally away from the point of origin

types of joint movement

angular motion

changing the angle of the shaft

ex) the pencil remains stationary, but the shaft changes angle relative to the surface

circumduction is angular movement

types of joint movement

rotation

types of mvmts

gliding

two opposing surfaces slide past one another

slight movement but can move in all directions

ligaments and joint capsule don't allow rotation

example: carpal and tarsal bones, sternoclavicular joint

types of joint movement

abduction

movement away from the longitudinal axis of the body in the front plane

type of joint movement

adduction 

movement towards the midline of the body

types of body movement

flexion

types of body movement

extension

movement to return body part to anatomical position

increases the angle between articulating elements

types of body movement

hyperextension

types of joint movements

circumduction

types of joint movements

rotation

left/right rotation of head

medial/lateral rotation of limbs

pronation/supination

types of joint movements

eversion

types of joint movement

inversion

types of joint movements

dorsiflexion

types of joint movements

plantar flexion

type of joint movements

lateral flexion

types of joint movements

protraction

types of joint movements

retraction

moving a body part anteriorly in a horizontal plane 

ex) jaw

type of joint movements

opposition

type of joint movement

reposition

type of joint movements

elevation

type of joint movements

depression

structural class. of synovial joints

plane 

have flattened slightly curved facets

faces slide across one another

amount of movement is slight

ligaments usually restrict rotation

structural class. of synovial joints

hinge joints

permit angular movement in a single plane

like the opening and closing of a door

uniaxial or monoaxial 

structural class. of synovial joints

pivot joints

monoaxial

only permit rotation

atlantoaxial joint

structural class. of joints

condylar joints

an oval articular face nestles in a depression on the opposing surface

biaxial

along or across the length of the oval

structural class. of joints

saddle joints

complex articular facets

each resembles a saddle because it is concave on one axis and convex on one axis

biaxial

ex) thumb

structural class. of joints

ball and socket joints 

the round head of one bone rests within the cup depression in another

multiaxial

ex) shoulder and hip

jaw

modified hinge 

unique because the articular faces on the temporal/mandible bone are covered with fibrous cartilage not hyaline cartilage

thick disc of cartilage divides joint into 2 chambers

really 2 synovial joints

poorly stabilized

permits extensive motion

a forceful lateral movement can result in dislocation

shoulder joint

permits the greatest range of motion of any joint in the body

ball and socket

glenoid labrum (CT) covers joint, pt of attachmt

most of the stability is provided by ligaments and surrounding skeletal muscles/assoc. tendons

between the humerous and the ulna + radius

hinge

 flexion/extension 

extremely stable

bony surfaces interlock to prevent lateral mvmt and rotation

ligaments:

ulnar collateral

radial collateral

annular 

ball and socket

multiaxial

articular capsule keeps the head from moving away form the acetabulum

stabilized by ligaments: iliofemoral, pubofemoral, ischiofemoral

hip flexion is the most important mvmt

supporting body through activities like walking and running

hinge joint

much less stable than other hinge joints (allows some rotation)

articular capsule: lateral/medial menisci

supporting ligaments: patellar ligament, tibial collateral, fibular collateral, ACL, PCL

1. excitability: ability to respond to stimulation

2. contractibility: ability to shorten actively and exert a pull or tension that can be harnessed by CT

3. extensibility: ability to continue to contract over a range of resting lengths

4. elasticity: the ability of a muscle to rebound toward its original length after a contraction

1. produce skeletal movement

2. maintain posture and body position

3. support soft tissues

4. regulate entering and exiting of material

5. maintain body temperature

CT of a muscle

epimysium

layer of dense irregular CT that surrounds the entire skeletal muscle

separates the muscle from surrounding tissues and organs

connected to deep fascia

CT of muscles

perimysium

CT fibers divide the muscle into a series of compartments each containg a bundle of muscle fibers (fasicle)

contains numerous bvs and nerves that branch to supply each fasicle 

CT of muscles

endomysium

surrounds each muscle fiber

binds each muscle fiber to its neighbor

supports capillaries that supply individual fibers

delicate connective network of reticular fibers

scattered myosatellite cells lie between the endomysium and the muscle fibers

cells function in regeneration

CT of muscles

Tendons and Aponeuroses

at the end of each muscle, the collagen fibers at the epimysium perimysium and endomysium converge to form a fibrous tendon that attaches to muscle, skin, or another muscle

often resemble thick cords or cables

aponeuroses: thick, flattened sheets

CT (epi, peri, endo) contain blood vessels that supply muscle fibers

skeletal muscles = voluntary muscles

nerve fibers branch throughout the perimysium

communication between synapses occur at the neuromuscular synapses

microanatomy

sacrolemma

microanatomy

sarcoplasm

microanatomy

myoblasts

groups of embryonic cells fuse together to create individual skeletal muscle fibers

each nucleus in muscle fiber reflects a contribution of a single myoblast

microanatomy

myosatellite cells

myoblasts that do not fuse with developing muscle fibers but remain in adult skeletal muscle tissue

when a muscle cell is injured, myosatellite cells differentiate and assist in the repair/regeneration of muscle

Microanatomy

Transverse (T) tubules

deep indentations in the sacrolemmal surface form a network of narrow tubules that extend into the sarcoplasm

help stimulate and coordinate muscle contractions

can shorten, responsible for skeletal muscle fiber contraction

the myofibrils are attached to the sarcolemma at each end of the cell the contraction shortens the entire cell

mitochondria and glycogen granules are scattered among the myofibrils

breakdown of glycogen produces ATP

sleeve or membranes that is complex and similar to the smooth ER of other cell

plays essential role in controlling the contraction of indiv. myofibrils

tubules of the SR enlarge, fuse, and form expanded chambers called terminal cisternae

myofibrils consist of bungles of myofilaments

protein filaments consisting primarily of the protein actin and myosin

actin: thin

myosin: thick

the actin/myosin are organized in repeating units

smallest functional unit of the muscle fiber

M line: where thick filaments lie

Z line: where thin filaments lie

zone of overlap: where the thin filaments pass between the thick filaments

A band: area containing thick filaments

H band: thick filaments only

I band: thin filaments only 

actin

assoc. w/ proteins tropomyosin and troponin

before contraction the troponin molecules change position moving the tropomyosin molecules, exposing the active sites 

at the end of each set of thin filaments is the Z line

composed of a bundle of myosin filaments

molecules are oriented away from midline with their heads projecting outward toward the surrounding thin filaments

myosin heads are also known as cross-bridges because they connect thick/thin filaments during contraction

each thick filament has a core of titin

titin core is extremely elastic and will recoil after stretching

contracting muscle fiber exerts a pull or tension and shortens the length

muscle fiber contraction results from the interaction between thick/thin filaments in each sarcomere

mechanism for muscle contraction is the presence of calcium ions and ATP

muscle contraction

sliding filament theory
 

1. sliding occurs when the myosin heads of the thick filaments bind to active sites on the thin filaments

2. when cross-bridge occurs, myosin head pivots toward the M line, pulling the thin filament toward the center to the sarcomere

3. cross bridge detaches and returns to its original position

attach, pivot, detach, return

when the thick filaments pull on the thin filaments, the Z line moves toward the M line, and the sarcomere shortens

1. immediate trigger od contraction is the appearance of free Calcium ions in the sarcoplasm

the amount of intracellular calcium is usually low

2. electrical events (depolarization) on the sarcolemmal surface cause a contraction by triggering the release of calcium

3. electrical impulse travels along a nearby T tubule, the terminal cisternae become permeable to Ca 2+

4. these ions diffuse from the terminal cisternae into the zone of overlap where they bind to troponin

5. this changes the shape of the troponin molecules, moves tropomyosin molecules and exposes active sites

duration depends on the duration of electrical stimulation

1. for contraction to continue additional electrical impulses have to be conducted along T tubules

2. if electrical stimulation stops: sacroplasmic reticulum will recapture the Ca 2+, the troponin-tropomyosin complex will cover the active sites and contraction will end

3. ATP must bind to the myosin head before it will detach--muscle fibers will eventually stop contracting as they run out of ATP

1. chemicals released by the motor neuron at the neuromuscular synapse alter the transmembrane potential of the sarcolemma. 

2. the change in the transmembrane potential of the T tubules triggers the release of calcium ions by the sarcoplasmic reticulum 

each skeletal muscle fiber is controlled by a motor neuron located in the CNS--- its axon extends to the neuromuscular synapse

expanded tip of axon: synaptic terminal--contains numerous mitochondria and synaptic vesicles filled with molecules of acetylcholine----creates an action potential

Muscle Contraction 

Events

1. Actylecholine is released by the synaptic terminal and binds to sarcolemma's receptors

2. action potential that spreads to other T tubules

3. SR releases Ca 2+ ions, increase Ca concentration

4. Ca 2+ binds to troponin, troponin-tropomyosin complex exposes active sites on thin filaments, myosin cross bridges form, myosin heads bind to active sites

5. repeated cycles of cross-bridge binding, pivoting and detachment occur powered by the hydrolysis of ATP

EVENTS PRODUCE FILAMENT SLIDING

6. action potential ceases (ACh is broken down by enzyme AChE)

7. SR reabsorbs Ca 2+ ions, concentration declines

8. when ca ion concentrations reach normal levels, the troponin-tropomyosin complex returns to normal position--cover active sites

9. contraction ends

10. muscle relaxation occurs, and the muscle fiber returns passively to resting length

all of the muscle fibers controlled by a single motor neuron

resting tension in a muscle

stabilizes position of bones/joints

an enlargement of the muscle due to repeated exhaustive stimulation

fibers dev. a large # of mitochondria, a higher concentration of glycolytic enzymes and larger glycogen reserves

each myofibril contains a larger # of actin and myelin

types of muscle fibers

white fibers

fast fibers

large in diameter, densely packed with myofibrils, large glycogen reserves, and relatively few mitochondria

contractions use large amt of ATP

contractions largely supported by anaerobic glycolysis

types of muscle fibers

red fibers

slow fibers

only half the diameter of fast fibers

take three times as long to contract after stimulation

specialized to contract for extended periods of time, long after a fast muscle would be fatigued

mitochondria continues to produce ATP throughout the contraction

large # of mitochondria

aerobic metabolism 

O2: capillaries, myoglobin

types of muscle fibers 

intermediate

muscle shapes

parallel

fascicles are parallel to the longitudinal axis of the muscle

indiv. fibers may run entire length of muscle

most skeletal muscles are parallel

muscle shapes

convergent muscles

muscle shapes

pennate muscles

muscle shapes

circular muscles

fulcrum lies between the applied force and the resistance

ex) seesaw,neck muscles

the resistance is located between the applied force and the fulcrum 

ex) wheelbarrow

the force is applied between the resistance and the fulcrum

ex) biceps brachii, elbow flexion

leaves the spinal cord

contains the axons of somatic motor neurons and at some levels visceral motor neurons that control peripheral effectors 

distal to each dorsal root ganglion sensory/motor fibers form a single ___ nerve

classified as mixed nerves b/e they contain both afferent and efferent fibers

specialized membranes that provide protection, physical stability, and shock absorption

cover spinal cord and surround spinal nerve roots 

bvs branching within these layers deliver oxygen and nutrients to spinal cord

continuous with cranial meninges 

outermost covering of the spinal cord and brain

layer of dense irregular CT whose outer/inner surfaces are lined with simple sq. E

epidural space contains areolar tissue, bvs, and adipose tissue

middle layer that covers brain and spinal cord

subdural space separates it from dura mater

simple squamous epithelium

separated from pia mater by subarachnoid space which contains cerebrospinal fluid

innermost meningeal layer

blood vessels found in this layer 

composed of elastic/collagen fibers

firmly bound to underlying neural tissue

bound to other layers by denticulate ligaments 

organized into groups called nuclei

sensory nuclei: recieve/relay sensory info from proprioreceptors

motor nuclei: issue motor commands to peripheral effectors such as skeletal muscles

posterior gray horns: somatic and visceral sensory nuclei

anterior gray horns: contain neurons concerned with somatic motor control

lateral gray horns: visceral motor neurons

gray commissures: contain axons crossing from one side of the cord to the other before reaching a destination within the gray matter

arranged by columns:

1. posterior white column
2. anterior white column
3. anterior white commissure
4. lateral white columns

columns contain tracts whose axons share functional and structural characteristics

relatively uniform with respect to diameter, myelination, and conduction speed

conscious thought processes, intellectual functions

memory storage/processing

conscious and subconscious regulation of skeletal muscle contractions

diencephalon

thalamus

diencephalon

hypothalamus

centers controlling emotions, autonomic functions, and hormone production

pituitary gland located in this region

processing for visual and auditory data

generation of reflexive somatic motor responses

maintenance of consciousness

relays sensory information to cerebellum and thalamus

subconscious somatic and visceral motor centers

relays sensory info to thalamus and other portions of the brain stem

autonomic centers for regulation of visceral function (cardiovascular, respiratory, and digestive system activities)

coordinates complex somatic motor patterns

adjusts output of other somatic motor centers in brain and spinal cord 

diencephalon

epithalamus

inner region of gray matter surrounded by tracts of white matter

gray matter surrounds the fluid-filled ventricles and passageways that correspond to the central canal of the spinal cord 

gray matter forms nuclei

in cerebrum and cerebellum the white matter is covered by the neural cortex 

nuclei, centers and cortical areas of the cerebrum, cerebellum, diencephalon, and mesencephalon

output from these processing centers modifies the activities of nuclei and centers in the lower brain stem and spinal cord

nuclei and sensory info issue motor commands to peripheral effectors indirectly through the spinal cord/nerves or directly through the cranial nerves

fluid filled cavities (CSF) lined by ependymal cells

one ventricle within cerebral hemisphere, one in the diencephalon, one betweens the pons and cerebellum

begins between the pons and cerebellum

fourth ventricle is cont. with the central canal of the spinal cord 

circulation of CSF from the ventricles and central canal into the subarachnoid space through foramina in the roof of the ventricles 

surround the brain

provide protection, act as shock absorbers that prevent contact with surrounding bones

three layers: dura mater, arachnoid mater, pia mater

outermost layer 

two fibrous layers:

endosteal layer: fused to the periostem lining of the cranial bones

meningeal layer:connected to brain

dural sinuses: deliver blood to the internal jugular vein of the neck 

subdural space separates the opposing epithelia of the dura mater and the cranial arachnoid mater

subarachnoid space: contains a delicate weblike meshwork of collagen and elastic fibers that link the arachnoid mater to the underlying pia mater

arachnoid granulations: projections into the dura mater

tightly attached to the contours of the brain

anchored to the surface of the brain by the processes of astrocytes

highly vascular membrane that acts as a floor to support the large cerebral bvs as they branch over the surface of the brain

barrier that isolates CNS general blood supply to the brain

cells are extensively connected by tight junctions which prevent the diffusion of materials between adjacent endothelial cells

only lipid-soluble compounds can dissolve

water soluble substances can only cross through passive/active transport

• portions of the hypothalamus--high permeability to permit the diffusion of hypothalamic hormone
• capillaries in the pineal gland 
• choroid plexus: site of CSF production, increased permeability, modified ependymal cells

location where CSF is formed = choroid plexus

choroid plexus: combination of specialized ependymal cells and highly permeable capillaries

derived from plasma but not similar to blood

differences from blood: the blood contains high concentrations of suspended proteins, CSF does not, ion concentrations differ, 

1. CSF is produced in the lateral ventricles
2. flows into the third ventricle through the interventricular foramen
3. flows into the aqueduct of the midbrain
4. flows into the fourth ventricle by passing through the lateral apertures and single median aperture 
5. enters normal circulation through the arachnoid granulations

high demand for energy (glucose/lipids) limited reserves

neurons lack myoglobin (no oxygen storage)

most of the blood enters the brain through the internal carotid artery and exits through the internal carotid vein (drain dural sinuses)