Human Anatomy Lecture Exam 2

Joints

where two bones meet
fluid, cartilage, or fibrous tissue
Tradeoff flexibility & strength

Synarthrosis

no movement

Fibrous (Synarthrosis)

suture; surreal ligaments
and gomphosis; periodontal ligaments

Cartilaginous (Synarthrosis)

synchondrosis

Bony fusion (Synarthrosis)

synostosis

Amphiarthrosis

some movement

Fibrous (Amphiarthrosis)

syndesmosis; between tibia and fibula, and between fibula and talus

Cartilaginous (Amphiarthrosis)

Symphysis; pubis symphysis and intervertebral discs

Diarthrosis

free movement

Synovial joints

Have fibrous joint capsule, synovial membrane, articulate cartilages, and joint cavity containing synovial fluid

Synovial joints make up

Accessory structures, blood vessels, and nerves

Synovial fluid

lubricates articular cartilages & reduces friction and nourishes articular cartilage; shock absorber

Linear motion

Movement in a straight line.

Rotation

circular movement around an axis such as the shoulder joint

Angular motion

the motion of a body about a fixed point or fixed axis

Circumduction

the circular movement at the far end of a limb

Transverse plane

horizontal division of the body into upper and lower portions

Sagittal plane

divides body into left and right

Frontal plane

Divides the body into front and back portions.

Monoaxial

type of joint in which the bone can move in only one plane

Biaxial

movement in two planes; ribs and wrist

Triaxial

movement in three planes; shoulder, hip

Plane Joint

monaxial, slight linear motion

Example: sternoclavicular and acromioclavicular joints, intercarpal and intertarsal joints, vertebrocoastal joints, and sacro-iliac joints

Pivot joint

monoaxial, rotation

Examples: Atlanto-axial joint and proximal radio-ulnar joint

Saddle joint

biaxial, angular motion

Example: first carpometacarpal joint

Hinge joint

angular motion in a single plane, monaxial

Example: elbow joint, knee joint, ankle joint, and interphalangeal joint

Condylar joint

biaxial, angular motion

Example: Metacarpophalangeal joints 2 to 5, radiocarpal joint, and metatarsophalangeal joints

Ball and socket joint

Triaxial, angular motion, circumduction, & rotation

Example: shoulder joint and hip joint

Abduction

Movement away from the midline of the body (away from longitudinal axis)

Adduction

Movement toward the midline of the body (towards the longitudinal axis)

Flexion

Decreases angle between bones; "bends forward"

Extension

Increases angle between bones; "bends backwards"

Hyper extension/flexion

beyond normal limits

Eversion

moving the sole of the foot outward at the ankle

Inversion

Turning the sole of the foot inward

Dorsiflexion

bending of the foot or the toes upward

Plantar flexion

bends the foot downward at the ankle

Lateral flexion

Side-bending left or right

Retraction

moving a body part backward and parallel to the ground

Protraction

moving a body part forward and parallel to the ground

Opposition

Movement of the thumb to touch the fingertips

Reposition

return back to normal (anatomical position)

Depression

lowering a body part

Elevation

raising a body part

temporomandibular joint (TMJ)

2 synovial cavities in same space
Very loose
Allows for chewing
Plane & hinge

zygapophyseal joints

articular processes between vertebra
Limits Flexion, Extension, Rotation, and Lateral flexion

Intravertebral disc

Vertebral endplate, anulus fibrosus, and nucleus pulposus

Intravertebral ligaments

Ligamentum flavum, posterior longitudinal ligament, interspinous ligament, supraspinous ligament, and Anterior longitudinal ligament

Herniated/ bulging disc

a rupture of the nucleus pulpous through the annular wall of the disc and into the spinal canal

Sternoclavicular joint

only joint for axial and upper appendicular
two synovial cavities
two plane joints

Glenohumeral joint

ball and socket
greatest range of motion
triaxial

Elbow joint

3 joints w/in one capsule

2 hinge joints: flexion/extension

Humberto-ulnar: strongest; trochlea & tronchlear notch

Humeroradial: more flexible; capitulation & head of radius

1 pivot joint

proximal radio-ulnar

Proximal & distal radio-ulnar joints

pivot joints
allow rotation

proximal radio-ulnar joint

head of radius & radial notch of ulna

Annular & quadrate ligament

stabilize proximal joint

Distal radio-ulnar joint

Ulnar notch of radius & head of ulna

Radio-ulnar ligament & interosseous membrane

stabilize distal joint
allows for supination and pronation

Wrist joint

radiocarpal joint & intercarpal joints

Condylar joints

Flexion/Extension, Adduction/Abduction, Circumduction

example: radiocarpal joint

Saddle joints

Flexion/Extension, Adduction/Abduction; Opposition; Circumduction

carpometacarpal joint of thumb

Plane joint

intercarpal joints and carpometacarpal joint of little finger

Femur joint

ball and socket joint
fat pad absorbs shock

Knee ligaments prevent

hyperextension or hyperflexion
extensive adduction or abduction

Cruciate ligaments

allow locking and unlocking of the knee; stand for long periods

Knee joint

works as a hinge joint;
ligaments, menisci, tendons, bursa, & fat pad all stabilize this joint

Anterior cruciate ACL

Locks knee in extended position

Medial & lateral menisci

shock absorbers
lateral stability
increase surface area of joint
changes shape to support articular surface

ligaments that stabilize the knee joint

fibular collateral ligament, popliteal ligaments, posterior cruciate ligament, anterior cruciate ligament, tibial collateral ligament, patellar ligament

Talocrural joints

Hinge: talus, tibia & fibula

Tibiotalar joint

hinge, main joint, bears body mass; supported by:
proximal tibiofibular joint (plane joint),
distal tibiofibular joint (fibrous syndesmosis), and
fibulotalar joint (fibrous syndesmosis)

Condylar joints

metatarsophalangeal joints

Hinge joints

Interphalangeal joints

Plane joints

Talonavicular joint, Intertarsal joints, Tarsometatarsal joints, and Calcaneocuboid joint

Smooth muscle

Non-striated, can replicate; hyperplasia, reflex arcs or myogenic

Cardiac muscle

Myogenic, branched, scar tissue, pumps blood

Skeletal muscle

multinucleate, pulls on bones, voluntary or reflex arc, hypertrophy

Muscle tissues share 4 basic properties

Excitability, Contractility, Extensibility, and Elasticity

Excitability

ability to respond to stimuli; undergo Action Potentials

Contractility

ability to shorten & exert tension

Extensibility

contract over a range of resting lengths

Elasticity

recoil to original length

Skeletal muscle

Produces movement, Maintain posture & body position, Support soft tissue, Regulate entering & exiting of material; found in some sphincters, and Maintains body temperature; shivering thermogenesis

Connective tissues of Skeletal Muscle (organ)

epimysium, Muscle fascicle, Endomysium, and Perimysium

Connective tissues of Muscle Fascicle (bundle of cells)

Perimysium (A), Muscle fiber (B), and Endomysium (C)

Connective tissues of Muscle Fiber (cell)

Sarcolemma (B), Myofibril (C), Endomysium (G), and Myosatellite cell (H)

Muscle fiber (cell)

Myosatellite cell, Myofibril, Sarcolemma, Nuclei, Muscle fiber, Sarcoplasm

Mitochondria, Sarcolemma, Myofibril, Thin filament, Thick filament, Triad, Sarcoplasmic reticulum, T tubules, Terminal cisterna, Sarcoplasm, and Myofibrils

myofilaments to muscle

Myofilaments -> Sarcomere -> Myofibril -> Muscle fiber -> Fascicle -> muscle

Myofilaments

Sarcomere

smallest contractile unit of muscle

Myofibril

Muscle Fiber

Fascicle

Muscle

Sarcomere Structure

Sliding filament theory

(1) Rigor is a transient site
(2) ATP binding dissociates myosin from actin. The cross-bridge can now go through a cycle o a new G-actin molecule
(3) Myosin ATPase hydrolizes ATP to ADP and Pi. Energy from the reaction is transferred to the cross-bridge. ADP and Pi remain bound to myosin.
(4) The myosin head moves to the cocked position and binds to a G-actin molecule.
(5) Myosin attachment to actin triggers rapid Pi release and the power stroke. The actin filament is moved about 10 nm towards the center of the sarcomere.
(6) The myosin head and unbinds ADP and remains tightly bound to actin (rigor).

Action potential (AP)

rapid change in membrane potential over surface of cell

Excitable cells that have action potential

Muscles, Sensory cells, Neurons, and some endocrine cells

Excitable cells may secrete a signaling molecule due to AP

Skeletal muscles are stimulated via

reflex arcs and voluntary motor units