UArrk Anatomy lec exam 2

synarthosis

immovable joint

amphiarthosis

slightly movable joint

diarthrosis

freely movable joint

Synarthosis-sutures

joints found only in the skull
bones are interlocked together
immovable

synarthrosis-gomphosis

joints between teeth and jaw bones
periodontal ligaments of the teeth
immovable

synarthrosis-synchondrosis

joint within epipysis of bone
immovable
binds diaphysis to the epiphysis

synarthrosis-synostosis

joint between two fused bones
fusion of the three coxal bones
immovable

subgroups of the synarthrosis joints

sutures, gomphosis, synchondrosis, synostosis

subgroups of the amphiarthroses joints

syndesmosis, symphysis

amphiarthroses-syndesmosis

ligaments that connect two bones but limit their motion
between ulna and radius
between tibia and fibula

amphiarthroses-symphysis

bones are separated by a wedge or pad of cartilage
between the pubic bones of the two coxal bones

synovial joints

diarthroses joints are also called

examples of diarthroses joints

shoulder joint, elbow joint, hip joint, knee joint

synovial joint

more movement, more injury, less strength

angular movements

abduction/adduction
flexion/extension

abduction

away from midline

adduction

towards midline

flexion

reduces angle between articulating elements

extension

increases angle between articulating elements

special movements

inversion/eversion
dorsiflexion/plantar flexion
lateral flexion
protraction/retraction
opposition
depression/elevation

inversion

turning sole inward
causes more injury

eversion

turning sole outward

dorsiflexion

foot upwards(toes up)

plantar flexion

foot downwards(stepping on gas)

lateral flexion

vertebral column bends to the side

protraction

jaw outward, cross arms

retraction

back to normal, jaw back, arms uncrossed

opposition

thumb with any other finger pressed together

depression

move something downward(inferior)

elevation

move something upward(superior)

gliding joint

monaxial
slight linear motion
clavicle and manubrium

pivot joint

monaxial
rotation
joint at C1 and C2

saddle joint

biaxial
angular motion
looks like saddle
carpometacarpal joint

hinge joint

monaxial
angular motion
elbow joint, knee joint, ankle joint

ellipsoid joint

biaxial
angular motion
metacarpophalangeal joint
WRIST area
looks like stamp

ball and socket joint

triaxial
angular motion, circumduction, rotation
shoulder joint, hip joint

skeletal muscle

pulls on skeletal bone, voluntary contraction

cardiac muscle

pushes blood through arteries and veins, rhythmic contractions

smooth muscle

pushes floods and solids along the digestive tract(example)
involuntary contraction

4 basic properties of muscle

excitability, contractibility, extensibility, elasticity

excitability

ability to respond to stimuli

contractibility

ability to shorten and exert a pull or tension

extensibility

ability to continue to contract over a range of resting lengths

elasticity

ability to rebound toward its original length

skeletal muscle functions

produce skeletal movement
maintain posture and body position
support soft tissue
regulate entering and exiting of material
regulate body temperature

epimysum tissue

dense tissue that surrounds entire muscle

perimysium

dense tissue that divides the muscle into parallel components of fascicles(muscle fibers)

endomysium

dense tissue that surrounds individual muscle fibers

structural order of organization of skeletal tissue

skeletal muscle-EPIMYSIUM
muscle fascicle-PERIMYSIUM
muscle fiber(cell)-ENDOMYSIUM

calcium ions

what ion triggers muscle contraction

sarcolemma

membrane that surrounds the muscle cell

sarcoplasm

cytosol of the muscle cell

myofibirls

sarcoplasm contains

myofibrils

responsible for the contraction of muscles

sarcoplasmic reticulum

surrounding each myofibril is the

myofilaments

myofibrils are made of

thin protein filaments

actin

thick protein filaments

myosin

sacromere organization

myosin and actin both arranged in repeating units called sacromeres

sacromere

main functioning unit of muscle fibers
consists of overlapping actin and myosin
overlapping creates the striations that give skeletal muscle its identifiable characteristic

each sacromere consists of

z line
i band
a band(cause striations)
h band
m line

myosin

dark purple

actin

light pink

h band

myosin/thick filament only

a band

myosin and actin

smaller

upon contraction: H and I bands get

larger

upon contraction: zone of overlap gets

closer together

upon contraction: z lines move

remains constant

upon contraction: A band

troponin

holds tropomysin in position

tropomysin

protein that covers the binding sites when the muscles is relaxed

T-tubule function

conduct impulses getting active potential to start sarcoplasmic reticulum

acetylcholine

the main neurotransmitter involved with skeletal muscle contraction

1:contraction cycle begins

acetylchloine released causes release of calcium ions from the SR

2:active site exposure

calcium ions bind to troponin
tropomyosin molecules rolls away from active sites

3:cross bridge formation

myosin heads bind to active sites

4:myosin head pivoting

energy released as myosin heads pivot toward M line

5:cross bridge detachment

ATP binds to myosin heads, breaking cross bridge

6:myosin reactiviation

ATP reactivates myosin head and return to normal positions

3 major types of muscle fibers

fast, intermediate, slow

fast fibers

white fibers

intermediate fibers

pink fibers

slow fibers

red fibers

fast fiber characteristics

large in diameter
large glycogen reserves
few mitochondria
muscles contract using ANAEROBIC metabolism
fatigue easily
can contract in .01 seconds or less after stimulation
produce powerful contractions

slow fiber characteristics

HALF the diameter of fast fibers
take 3 TIMES longer to contract after stimulation
can contract for extended periods of time
contain abundant myoglobin(red color)
muscles contract using AEROBIC metabolism
large network of capillaries

intermediate fiber characteristics

similar to fast fibers: low myoglobin, high glycolytic enzyme concentration, ANAEROBIC metabolism
similar to slow fibers: lots of mitochondria, greater capillary supply, resist fatigue

fast fibers

eye and hand muscles
sprinters
intense workouts

slow/intermediate fibers

back and leg muscles
marathon runners
training for long distance

prime movers(agonists)

responsible for producing a particular movement

antagonists

actions oppose the action of the agonist

synergists

assist the prime mover in performing an action

fixaters

agonist and antagonist muscles contracting at the same time to stabalize a joint

primer mover example

biceps brachii-flexes the lower arm

antagonists example

triceps brachii-extends the lower arm

synergists example

latissimus dorsi and teres major
contract to move the arm medially over the posterior body

fixators example

flexor and extensor muscles contract at the same time to stabiliaze an outstretched hand

first class lever

fulcrum(joint) lies between the applied force and the resistance force(opposed force)

first class lever example

tilting the head forward and backward

second class lever

resistance is located between the applied force and the fulcrum(joint)

second class lever example

standing on your tiptoes