A&P Exam 3 Flashcards
Articulation
where two bones connect to allow for body movements
- bone & teeth
- bone & cartilage
Joint Classification
- Functional (based on ROM of joint)
2. Structural (relies on anatomical organization of joint)
Joint Structure
Determines direction & distance of movement (ROM)
Joint stability decreases as joint mobility increases
Synarthrosis
Functional Classification
immovable, VERY STRONG
edges of bones may touch
Amphiarthrosis
Functional Classification
slightly movable
EX:
Diarthrosis
Functional Classification
freely movable
EX: ALL SYNOVIAL JOINTS
Examples of Synarthrosis Joints
- Suture -bound by dense connective tissue
- Gomphosis -fibrous connection
Binds teeth to socket - Synchondrosis -ridgid cartilaginous bridge between two bones
EX: epiphyseal plate, ribs & sternum
Examples of Amphiarthrosis Joints
- Syndesmosis -bones connected by ligaments
EX: distal tibiofibular joint ligament - Symphysis -bones seperated by fibrous cartilage
EX: pubic symphysis & intervertebral disks
Syndesmosis
High ankle sprain
Examples of Diarthrosis Joints
MOST COMMON JOINT IN THE BODY
surrounded by fibrous articular capsule
lined with synovial membrane
Components of Synovial Joints
- Articular Cartilages (hyaline cartilage without perichondrium)
- Synovial Fluid
- Accessory Structures
Articular Cartilages (hyaline minus perichondrium)
Avascular
smooth surface with minimal friction
articular surface of bone
damage=loss of smooth surface & replacement of rough collagen fibers (osteoarthritis)
Synovial Fluid
oily, viscous
prevents articular cartilage from touching
lubrication
nutrient distribution when joints move (waste absorbed through areolar tissue)
NO BLOOD!
Accessory Structure
cartilages -fibrous pad/articular disk
fat pads -localized masses of adipose tissue
ligaments -support & stabalize
tendons -limit ROM, dense regular connective tissue
bursae -reduce friction
Bursae
pockets of synovial fluid in thin connective tissue
Factors that stabalize
collagen fibers of joint capsule & ligaments that cross it
shape of articulating surfaces
tensionin tendons
Fat Pads
high amounts of sensory nerves
superficial to joint capsule
Types of dynamic motion
Linear (Gliding)
Angular
Linear Motion
movement of a bone parallel to plane of adjoining bone
all parts of bone move the same distance
NO ROTATION
EX: carpals, tarsals, scapular joint
Angular Motion
movement of a bone around a fixed point
EX: flexion & extension
goniometer
Gliding Joint (Plane joint)
Intercarpal
nonaxial
Hinge Joint
angular motion in a single plane
uniaxial
elbow, knee, DIP PIP
Pivot Joint
rotaion
uniaxial
EX: radioulnar (allows for supination & pronation)
Atlantoaxial
Ellipsoid Joint (Condylar)
oval articular face within a depression
biaxial
EX; MCP
Saddle Joint
two concave, straddled joints
CMC (thumb)
Ball & Socket Joint
convex head and a concave surface
multiaxial joint
EX: hip - glenohumeral joint
Intervertebral Articulations
Synovial Joints
C2 to L5 spinal vertebral articulate
Facet Joints
Inferior and Superior articular processes
Symphysis
Between adjacent vertebral bodies
Intervertebral Disks
pads of fibrous cartilage
seperate vertebral bodies
anulus fubrosis
nucleus pulposis
Anulus Fibrosis
contains sensory nerves
tough outer layer
attaches disk to vertebrae
Nucleus Pulposis
elastic, gelatinous core
Absorbs shock
ACIDIC to nerves
Intervertebral Ligaments
bind vertebrae together & stabalize vertebral column
Anterior Longitudinal Ligament-connects anterior bodies
Posterior Longitudinal Ligament -connects posterior bodies
close to spinal cord
Ligamentum Flavum -connects lamina
Shoulder Joint
Glenohumeral Joint
LEAST stable
skeletal muscles, tendons, ligaments, capsule
Socket of Shoulder Joint
Glenoid Labrum
deepens socket of glenoid cavity
fibrocartilage lining
SLAP lesion - overhead
BANKART - shoulder dislocation
Ligaments of Shoulder Joint
Glenohumeral
Coracoacromial
Coracoclavicular
Acromioclavicular -shoulder spereation
Muscles of Shoulder Joint
Supraspinatus
Infraspinatus
teres minor
subscapularis
Bursae of Shoulder Joint
Subdeltoid -deep to deltoid muscle
Elbow Joint
stable hinge joint
thick capsule
strong ligaments
articulates with humerus, ulna, radius
Humeroulnar Joint
trachlea (hum) with the ulna
-flexion & extension
Humeroradial Joint
capitulum of humerus with head of radius
Supporting Structures of Elbow Joint
Biceps
LCL
Annular Ligament (wraps around head of radius)
MCL
Nursemaid’s Elbow
swinging around child
radius pops out of elbow
Hip Joint
Stable, ball & socket joint
Stuctures of Hip Joint
Head of Femur & Acetabulum
Acetabular Labrum
Ligaments of Hip Joint
Iliofemoral Ligament
-prevents hyperextension of the hip
(polio gate)
Knee Joint
complicated hinge joint
trandfers weight between femur and tibia
Articulations of Knee Joint
Tibiofemoral Joint (Knee) Patellofemoral Joint
Menisci of Knee Joint
Medial & Lateral-
Fibrocartiliginous pads
cushion & stabalize joint
Ligaments of Knee Joint
Patellar ACL PCL MCL LCL
Injuries
Sprain -partial or complete tear of fibers of a ligament
Strain -partial or complete tearing of fibers of a muscle
Herniated Disk
portion of the disk bulges through annulus fibrosis
Bursitis
inflammation of bursae
Tedonitis
inflammation of tendon
Labral Tear
tear of the glenoid labrum or the acetabular labrun from bone
Meniscal Tear
tear of the meniscus in the knee
Herniated Disk Surgery
- muscle weakness
- sensory changes - numb, tingling
- loss of bowel/bladder
**NOT PAIN
Fascicle Arrangement
- Parallel
- Convergent
- Pennate
- Circular / Sphincter
Parallel Muscle
Fascicles parallel to long axis of the body
Advan: large ROM
Dis: not as strong as pennate
EX: Biceps Brachii
Convergent Muscle
Fascicles extending over a broad range converge on a single attachment site
Advan: versitile -stimulation of different portions can change direction of pull
EX: Pectoralis Major
Pennate Muscle
Fascicles form an angle with the central tendon that runs through the muscle
Advan: smaller ROM, but increased strength compared to parallel
EX: unipennate = intrinsic of the hand
bipennate = rectus femoris
multipennate = deltoid
Circular Muscle of Sphincter
Fascicles are concentrically arranged around an opening
when muscles contract, the diameter of opening decreases
EX: orbicularis oris
Origin
end of muscle that is fixed
proximal
Insertion
the end of muscle that is movable
distal
Action
Movement a muscle produces when it contracts
DESCRIBED: bone that is moved
joint
Agonist / Prime mover
a muscle responsible for a specific movement
Antagonist
a muscle that opposes the movement of an antagonist
Synergist
a muscle that assists a prime moverin performing its primary function
ELBOW FLEXION
Agonist
Antagonist
Synergist
Agonist -Biceps & Brachialis
Antagonist -Triceps
Synergist -flexors of the wrist
General Functions of Nervous System
- collect information by recptors from changes in environment called stimuli
- process and evaluate info
- initiate response to info (muscle contraction or gland secretion)
Central Nervous System
Spinal Cord & Brain
Neural tissue, connective tissues, blood vessels
Functions of PNS
deliver sensory outside of CNS
carry motor commands to peripheral tissues and systems
Functions of CNS
sensory data: from inside and outside of body
motor commands: control activities of peripheral organs (skeletal muscle)
higher functions of brain: intelligence, memory, learning, emotion
Sensory nervous system
Afferent NS
responsible for recieving information from receptors that detect stimuli and transmit info to CNS
Recptors
Detect changes or respond to stimulus
-complex sensory organs: ears, eyes, nose
Somatic Sensory
(Body)
detect stimuli that we consciously perceive
eyes, ears, skin
Visceral
organ
detect stimuli we do not consciously perceive
receptors located in BV, internal organs–chemical/ph/pressure change
Motor Nervous System
Efferent NS
responsible for initiating or transmitting motor output from CNS to effectors
controls muscle tissue and glands
Somatic Motor
effector is stimulated by conscious control
EX: voluntary skeletal muscle
Autonomic Motor
innervates and regulates without conscious control
cardiac muscle, smooth muscle, glands
- sympathetic
- parasympathetic
Sympathetic Division of Autonomic
has a stimulating effect
Fight or Flight
Parasympathetic Division of Autonomic
has a reflecing effect
breath, rest, digest
Peripheral Nervous System
all neural tissue outside the CNS
-spinal nerves, peripheral nerves, cranial nerves
Neurons
- Excitability
- Conductivity
- Secretion
- Extreme longevity
- Amitotic
Neurons
basic functional unit of the nervous system
Cell Body (Soma)
conduct electrical signal to axon from dendrites or initiated in cell body
large nucleus & nucleolus
Perikaryon -cytoplasm
RER & Ribosomes produce neurotransmitters
cytoskeleton
nissle bodies
Nissle Bodies
dense areas of RER and ribosomes
make neural tissue appear gray (gray matter)
Dendrites
highly branched
receive info from other neurons & transmit to cell body
Axon (nerve fiber)
typically long
carries electrical signals (action potential) to target
Axon Hillock
triangular section of cell body
Axon Collaterals
few side branches
Telodendria
fine extensions of distal axons
Synaptic Knobs
extreme tips of telodendria containing synaptic vesicles
Neuron Transprot
substances are moved in both directions of neuron
FAST= ATP; ex: vesicles, organelles, waste
moves along neurotubules
SLOW= enzymes, new axoplasm
moves along axoplasm
Presynaptic Cell
neuron that sends message
Postsynaptic Cell
cell that receivs message
Synaptic Cleft
small gap that seperates the presynaptic membrane and the postsynaptic membrane
Synaptic Knob
expanded area of axon of presynaptic neuron
Neurotransmitters
chemical messengers (ACh, dopamine)
released at presynaptic cleft
affect receptors of post synaptic membrane
broken fown by enzymes and reassembeled at synaptic knob
Neuromuscular Junction
synapse between neuron and muscle
Neuroglandular Junction
synapse between neuron and gland
Unipolar Neurons (Structural)
found in sensory neurons of PNS
very long axons
fused dendrites and axon
Multipolar Neurons (Structural)
common in CNS
ALL skeletal muscle motor neurons in PNS
long axons and multiple dendrites
Sensory Neurons (Functional)
afferent neurons of PNS
Motor Neurons (Functional)
efferent neurons of PNS
Interneurons (Functional)
neurons that go between two neurons
ONLY IN CNS, high number!
Glial Cells
Half the volume of the nervous system
capable of MITOSIS!
donot transmit nerve signals
Ependymal Cell
(CNS)
cuboidal cells with highly branched processes
form epithelium called ependyma
line central canal of spinal cord & ventricles of brain (CSF)
FUNCTION: secrete cerebrospinal fluid
stem cells & have cilia to circulate CSF
Astrocytes
abundant (90%)
large cell bodies with many processes
maintain blood-brain barrier
assist in neural development of the fetal brain
Astrocytosis
astrocytosis occupy space of dying neurons
Oligodendrites
(CNS)
smaller cell bodies with processes that wrap around acons to form myelin
myelin prevents passage of ions
increases speed of action potential
makes nerve appear white
internodes
myelinated segments of axon
nodes
gaps between internodes
Microglia
(5%)
smallest & least numerous neuroglia
phagocytic cells of immune system
Satellite Cells
Surround ganglia
regulate environment around neuron
Schwann Cells
form myelin sheath around peripheral axons
Myelination
Process in which part of axon is wrapped wih myelin
HIgh in lipids
In CNS = OLIG myelinates myelinates multiple neurons
SCHWANN cells in PNS myselinates ONE neuron
Axon Regeneration
Damaged PNS axons can regenerate if cell body is intact and some neurolemma remain
DEPENDS:
amount of damage
distance between site of damaged nerve & structure innovated
STEPS of axon regeneration
- axon is severed
- proximal portion seals off & swells due to axoplasmic flow
- part of myelin sheath and endoneurium form a regeneration tube
- axon regenerates & remyelination occurs
- innervation is restored when it comes into contact with original structure
- axon distal to injury regenerates
Nerve Regeneration in CNS
limited by chemicals released by growth-inhibitory chemicals that block axon growth
Astrocytes
produce scar tissue & DONT REGENERATE
Chemically Gated Channels
normally closed
open in response to neurotransmitter binding to receptor
Voltage-Gated channels
normally closed
open in response to changes in electrical charge potential across plasma membrane
only allow specific ions to pass through
activation gate & inactivation gate
States of Voltage-Gated NA+ channels
Resting State- inactivation gate is open & activation gate is closed
Activation State- inactivation gate is open and activation gate is open
Inactivation State- inactivation gate is temporarily closed and activation gate is open
*during this time, it cannot be stimuated to open
Dendrites & Cell Body
receptive segement
chemically gated channels
Axon Hillock
(Initial Segment)
Voltage gated Na+/K+ channels
Axon and Telodendria
(Conductive)
voltage-gated Na+/K+ channel
Synaptic Knobs
(Transmissive)
Ca++ channels & Ca++ pumps
Electrical Gradient
differencein electrical charge between 2 areas at the membrane
Inside = (-) Oustide = +
when membrane potential is altered it creates and electrical current
Chemical Concentration Gradient
unequal distribution between two areas for that substance
