Chapter 1 Flashcards
axial skeleton
central upper body. (skull, vertebral column, ribs, sternum)
no limbs
appendicular skeleton
pelvis & limbs
everything that isn’t central upper body
fibrous joints
characteristics
no movement
ex. skull sutures
cartilaginous joints
characteristics
limited movement
ex. vertebral disks
synovial joints
characteristics
allow high movement
low friction
hyaline cartilage
covers ends of articulating bones in synovial joints
synovial fluid
fills the capsule around synovial joints to aid low friction movement
uniaxial joint
characteristics
moves on one axis
ex. elbow
biaxial joint
characteristics
movement on 2 perpendicular axes
ex. wrist, ankle
multiaxial joint
characteristics
movement in all 3 axes
ex. hip, shoulder
vertebral column
characteristics
7 cervical (neck)
12 thoracic (upper & middle back)
5 lumbar (lower back)
5 sacral (fused) (back of pelvis)
3-5 coccygeal
epimysium
outside covering of muscle
bone periosteum
outside covering of bone
tendon
end of muscle that attaches to bone periosteum
proximal attachment of muscle
definition
closer to trunk
distal attachment of muscle
definition
further from trunk
superior attachment of muscle
definition
closer to head
further from feet
inferior attachment of muscle
closer to feet
further from head
muscle fiber
muscle cell
muscle fiber characteristics
many nuclei
long
cylindrical
fascicle
bundle of muscle fibers
perimysium
outside covering of muscle fascicle
endomysium
outside covering of muscle fiber
sarcolemma
membrane of muscle fiber (muscle cell)
covers endomysium
motor neuron
nerve cell that innervates muscle fibers
neuromuscular junction
meeting spot of motor neuron and muscle fiber
each fiber has it’s own
motor unit
a motor neuron and all its fibers
sarcoplasm
characteristics
cytoplasm of a muscle cell
has contractile proteins, other proteins, fats, mitochondria, enzymes, sarcoplasmic reticulum, etc.
myofibril
made of myofilaments arranged into sarcomeres
myofilament
actin
myosin
actin
thin myofilament
(actin particles in double helix arrangement.
troponin at intervals & tropomyosin in groove)
myosin
characteristics
thick myofilament
fibrous tail, hinge, globular head
crossbridge
the meeting of the myosin head with the actin filament
number of crossbridges dictates force production
sarcomere
contractile unit of muscle
sarcoplasmic reticulum
system of tubes in muscle fiber that stores calcium ions in vescicles
t-tubules
run perpendicular to sarcoplasmic reticulum to deliver calcium ions to depths of muscle fiber
action potential
electrical nerve impulse leading to contraction
sliding filament theory
myosin pulls actin in toward middle of sarcomere
troponin
high affinity to calcium ions. found on actin filament. shifts when calcium is released.
tropomyosin
in double helix of actin filament
shifts when troponin shifts allowing for strong crossbridge.
power stroke
pulling action of myosin heads
acetylcholine
neurotransmitter that diffuses across the neuromuscular junction when action potential arrives and excites the sarcolemma (releasing calcium)
all-or-none principle
all fibers in a motor unit contract. not just some
twitch
brief contraction from each action potential
tetanus
maximal fusion of twitches
muscle spindle
proprioceptor causing contraction when muscle is stratched
Golgi tendon organ
proprioceptor causing relaxation when too much tension in muscle
atrium
heart chamber. receives blood from body (right) and lungs (left). delivers blood to ventricles
ventricle
receives blood from atria. delivers blood to body (left) and lungs (right)
tricuspid valve
an AV (1 of 2 atrioventricular valves) between right atrium & ventricle
mitral valve (bicuspid)
an AV (atrioventricular valve) between left atrium & ventricle
systole
ventricular contraction
diastole
ventricular relaxation
aortic valve
1 of 2 semilunar valves between aorta and left ventricle
pulmonary valve
1 of 2 semilunar valves between pulmonary artery and right ventricle
sinoatrial node (SA)
function, location
pacemaker. initiates rhythmic electric pulse. immediately spreads to atria
upper lateral wall of right atrium
atrioventricular node (AV)
function, location
delays impulse from SA node slightly
posterior septal wall of right atrium
atrioventricular bundle (AV)
conduction fibers that send electrical impulse from AV node to ventricles via left and right bundle fibers
left bundle branch
splits off from AV bundle and conducts impulse deep into left ventricle
right bundle branch
splits off from AV bundle and conducts impulse deep into right ventricle
Purkinje fibers
splits off from L&R bundle branches. completely penetrates ventricles and takes electric impulse even deeper
sympathetic nervous system
effect on heart
Raise heart rate (accelerates depolarization rate of the SA node)
parasympathetic nervous system
Lowers heart rate (SA node discharge rate)
brachycardia
less than 60 beats/min
tachycardia
more than 100 beats/min
ECG - electrocardiogram
graphical representation of the heart’s electrical activity
depolarization
electrical stimulus that causes contraction
inside of membrane (- –> +)
outside of membrane (+ –> -)
P-Wave
shows depolarization in atrial muscle cells
QRS complex
shows ventricular depolarization
atrial repolarization is obscured, but occurs here as well
T-wave
Shows ventricular repolarization
arterial system
blood away from heart
venous system
blood towards heart
arterioles
branches of arteries that regulate blood flow to capillaries
capillaries
site of exchange of oxygen, fluids, nutrients, electrolytes, hormones, etc. between blood and body tissues
venules
collect blood from (and contiguous with) capillaries. turns into veins
hemoglobin
function, location
iron-protein that transports oxygen
also, regulates a hydrogen ion concentration
hemoglobin is found in red blood cells
repolarization
recovery from state of depolarization (t-wave)
trachea
first generation respiratory passage.
initial air intake location
red blood cells
transports oxygen via hemoglobin
helps with CO2 removal
bronchi
right and left
second generation passage
bronchioles
function, how many generations
about 23 generations
carry air to lungs
alveoli
final generation of air passages where O2 and CO2 are exchanged with blood
pleural pressure
the pressure between chest pleura and lung pleura (slightly negative)
pleura
membranes around lungs and that line chest wall
diffusion
molecule movements through membrane
alveolar pressure
the pressure inside alveoli
<1 ATM when inhaling, >1 ATM when exhaling
proprioceptor
sensory receptors in joints, muscles, and tendons.
relays information about pressure & tension subconsciously
extrafusal fibers
normal muscle fibers on outside of muscle belly
intrafusal fibers
fibers of muscle spindles located inside muscle belly
fast-twitch fiber
develops force and relaxes rapidly
slow-twitch fiber
develops force and relaxes slowly
myocardium
heart muscle
Type I fiber characteristics
efficient fatigue resistant, much aerobic energy, low myosin ATPase activity, low anaerobic power, low motor neuron size, high capillary density, high myoglobin content, high mitochondrial density
Type II fiber characteristics
inefficient, fatigue rapidly, low aerobic power, rapid force, high myosin ATPase activity, high anaerobic power
