Question | Answer |
cardiovascular system includes | heart,arteries,veins,capillaries |
pericardium | encloses heart & proximal ends of large blood vessels thats its attached |
layers of cardiac wall | epicardium
myocardium
endocardium |
epicardium | outer protection from friction
connective tissue beneath epithelium |
myocardium | thick middle layer, cardiac muscle tissue pumps blood out of heart chambers |
endocardium | inner layer, epithelium & connective tissue contain many elastic & collagenous fibers |
blood flows through vena cavae & coronary sinus into right atrium through _, to right ventricle through pulmonary valve to pulmonary trunk into right & left _ to lungs, through pulmonary veins into _ through mitral valve to _ & through _ to aorta. | tricuspid valve
alveoli
left atrium
left ventricle
aortic valve |
vessels through blood flow from aorta to myocardium & back to right atrium | coronary arteries
cardiac veins
coronary sinus |
cardiac cycle | all events that take place in 1 complete heart beat |
S-A node | atrial syncytium
junctional fibers |
A-V node | A-V bundle
bundle branches
purkinje fibers
ventricular sncytium |
normal ECG pattern | PQRST |
P wave | depolarization of atria |
QRS wave | depolarization of ventricles |
T wave | repolarization of ventricles |
nervous system regulates cardiac cycle | parasymphatethic & sympathetic nerve fibers control S-A node
auntonomic NS |
artery | strong, elastic vessels adapted carrying blood away from heart under high pressure |
arterioles | vessels subdivide progressive thinner tubes, eventually finer branched |
artery>arterioles | artery branches into arterioles |
control of vasoconstriction | impulses on vasomotor fibers stimulate smooth muscles to contract, reducing diameter of vessel |
control of vasodilation | vasomotor impulses inhibited, muscle fibers relax, diameter of vessel increases |
structure of capillary | smallest diameter blood vessels, connecting smallest arterioles & venules |
capillary physiology | substances in blood are excahnged for substances in tissue fluid surrounding body cells |
diffusion between blood and tissue | depends on concentration gradient, filtration forces molecules through w/ hydrostatic pressure |
why H2O & dissolved substances leave arteriolar end of capillary & enter venular end | colloid osmotic pressure unchanged, blood pressure decreased, reabsorption predominates |
vein | merged from a venule, carries blood back to atria, follows path of arteries |
venule | microscopic vessels continued from capillaries |
arterial blood pressure reaches its maximum when the ventricles contract | systolic pressure |
factors that influence blood pressure | blood volume
strength of hear contractions
heart rate
blood viscosity
peripheral resistance
venous blood flow |
blood volume | larger volume= more pressure, hemorrhage causes pressure to drop rapidly |
strength of heart contractions | stronger heart beat increases blood pressure |
heart rate | too fast= left ventricle wont have time to fill & will squeeze out much less blood to aorta |
blood viscosity | thicker blood= more pressure |
peripheral resistance | larger lumen of vessel= faster flow |
venous blood flow | contracting skeletal muscles
little pressure
breathing movements
vasoconstriction |
sympathetic reflexes in smooth muscle of vessels | vasoconstriction |
major factors that promote flow of venous blood | skeletal muscle contraction
breathing
arterial blood pressure |
pulmonary system | 12% total blood
right heart>lungs>left heart
O2 poor blood from heart>lungs
O2 rich blood back to heart |
systematic system | left heart>body>right heart
O2 rich blood to body cells
O2 poor blood back to heart |
aorta | largest diameter artery in body |
aorta principal branches | coronary
brachiocephalic
left common carotid
left subclavian arteries
descending aorta |
descending aorta | thoracic & abdominal group |
simple squamous | 1 layer, square epithelial tissue |
smooth muscle | non striated, autonomic NS |
cardiac muscle | striated, heart |
arteries | blood vessel from heart to rest body |
veins | vessel from body to the heart |
capillaries | tiny blood vessel, beginning of vein |
pulmonary | lungs |
systemic | body system |
tunica | tissue forming layer/covering of organ/part
tissue layers of blood vessel wall |
pulse | throbbing of arteries, by successive contractions of heart |
blood pressure | pressure by blood inner walls of arteries, elasticity/diameter of vessels and force of heartbeat |
card- | heart |
cusps | points |
phleb- | vein |
cardiovascular system physiology | pumps blood
closed system
1 RBC completes pathway every minute
maintain homeostasis of body fluids |
structure of heart | coverings
wall
chambers/valves
tissue |
size of heart | 5.5"x3.5" |
listen to heartbeat | between 5&6th ribs inferior to midpoint of left clavicle |
heart location | between lungs in lower portion of mediastinum
apex lies on diaphragm pointing left |
heart coverings | pericardium |
pericardial sac | pericardium |
heart wall | epicardium
myocardium
endocardium |
heart chamber & valves | atria
ventricles
intervenricular septum
tricuspid valve
bicuspid valve
pulmonary semilunar valve
aortic semilunar valve |
atria | receiving |
discharging | ventricles |
separates 2 halves | interventricular septum |
mitral | bicuspid |
heart tissue | intercalated discks contain gap junctions
desmosomes |
gap junctions | free movement of ions between cells |
desmosomes | joins cells together |