Lesson 7

ajv09c's version from 2015-04-27 14:20

Section 1

Question Answer
pulmonary circuitcarries blood to and from gas exchange surfaces of lungs, performed by the right side of the heart
systemic circuitcarries blood to and from the body, performed by left side of the heart
three types of blood vesselsarteries, veins, capillaries
capillaries are also calledexchange vessels; networks between arteries and veins; location where dissolved gases, nutrients, and waste products are exchanged between blood and tissue
four chambers of the heartright atrium, right ventricle, left atrium, left ventricle
right atrium function collects blood from systemic circuit
right ventricle functionpumps blood to pulmonary circuit
left atrium functioncollects blood from pulmonary circuit
left ventricle functionpumps blood to systemic circuit

Section 2

Question Answer
the heart is essentiallyinvoluntary muscular pump located in thoracic cavity
typical heart sizeabout 5 inches from the base to apex
heart is anatomicallyupside down base is superior to apex
great veins and arteries located atthe base of the hearrt
heart is surrounded by pericardial sac
heart sits betweentwo pleural cavities in the mediastinum

Section 3

Question Answer
pericardiumdouble lining of the pericardial cavity; consists of visceral pericardium, parietal pericardium, pericardial cavity
visceral pericardiuminner layer of pericardium
parietal pericardiumouter layer, forms inner layer of pericardial sac
pericardial cavitybetween parietal and visceral layers, contains pericardial fluid secreted by the pericardial membranes; lubricates and prevents friction. Infection of pericardium causing inflammation - pericarditis
the heart wall consists of epicardium, myocardium, endocardium
epicardiumpart of heart wall; outer layer; consists of visceral pericardium that covers heart
myocardiumpart of heart wall; middle layer; muscular wall of the heart
myocardium consists ofconcentric layers of cardiac muscle tissue. atrial myocardium wraps around great vessels; two divisions of ventricular myocardium
endocardiuminner layer of epithelium; lines surface of chambers
cardiac muscle tissue cardiac muscle cells connected by intercalated discs
intercalated discs secured bydesmosomes
desmosomestightly link cells together, convey force of contraction
gap junctionslink cytoplasm of cells together; propagate action potentials
characteristics of cardiac muscle cellssmall size; single, central nucleus; branching interconnections between cells; intercalated discs

Section 4

Question Answer
interatrial septumseparates atria
interventricular septumseparates ventricles
atrioventricular (AV) vlavesfolds of fibrous tissue that extend into openings between atria and ventricles
atrioventricular valves connectright atrium to right ventricle and left atrium to left ventricle
atrioventricular valves permitblood flow in one direction - from atria to ventricles
the right atrium receives blood fromsuperior vena cava, inferior vena cava, coronary sinus
superior vena cava receivess blood fromhead, neck, upper limbs, and chest
inferior vena cava recieves blood fromtrunk, viscera, and lower limbs
coronary sinuscardiac veins return blood to coronary sinus; coronary sinus opens into right atrium

Section 5

Question Answer
foramen ovale in the right atrium; before birth is an opening through interatrial septum; connects two atria; seals off at birth, forming a shallow depression called the fossa ovalis
right ventricle has chordae tendineae attach free edges from papillary muscles of ventricle
chordae tendineae/ papillary muscles preventvalve from opening backward (muscles tense before ventricular contraction)
right atrioventricular (av) valvecalled tricuspid valve; has three cusps; opening from right atrium to right ventricle; prevents back flow of blood
pulmonary circuit- right ventricle pushes bloodto pulmonary trunk through the pulmonary semilunar valve
pulmonary valve has ? cusps3
pulmonary trunk dividesinto left and right pulmonary arteries- leads to the left and right lungs
left atrium- blood gathers intoleft and right pulmonary veins; pulmonary veins deliver to left atrium
left atrium- blood passes toleft ventricle through left atrioventricular valve
left AV valve two cusped valve; bicuspid or mitral valve

Section 6

Question Answer
left ventricle holds same volume as right ventricle
left ventricle is ? than/as right ventriclelarger; due to thicker muscle needed to push blood through body
system circulation blood trackblood leave left ventricle through aortic valve into ascending aorta; ascending aorta turns (aortic arch) and becomes descending aorta
structural differences between left and right ventriclesright ventricle wall is thinner, develops less pressure than left ventricle; right ventricle is pouch shaped; left is round; damage/death of cells in right ventricle survivable since contraction of left ventricle also squeezes right ventricle and push blood into lungs
number of heart valves 4; two pairs; atrioventricular valves; semilunar valves
Atrioventricular valves locatedbetween atria and ventricles
atrioventricular valves work whenblood pressure closes valve cusps during ventricular contraction
atrioventricular valves stay in place bypapillary muscles that tense chordae tendineae to prevent valves from swinging into atria
semilunar valves locatedbetween ventricles and pulmonary trunk and ascending aorta
semilunar valve functionprevent back flow from pulmonary trunk and aorta into ventricles
semilunar valve have ? supportno muscular support
number of cusps in semilunar valve3
semilunar valves akapulmonary and aortic tricuspid valves
aortic sinuses locatedat base of ascending aorta
aortic sinuses function bysacs that prevent valve cusps from sticking to aorta
aortic sinuses originorigin of right and left coronary arteries- which are vessels that bring blood to cardiac tissue