the heart part 1

pulmonary circuit

O2 poor blood enters the pulmonary trunk which is the beginning of the pulmonary circuit, pulmonary trunk branches into left and right pulmonary artery because it is leaving the heart, pulmonary arteries carry O2 poor blood high in CO2 to the lungs, lungs remove CO2 from blood and put O2 into blood, O2 rich blood leaves the lungs and returns to the left atrium via the pulmonary veins because its returning to the heart

right side of the heart

O2 poor blood enters the right atrium via the superior and inferior vena cavae, atria contract causing O2 poor blood to travel from right atrium to right ventricle through the av tricuspid valve, ventricles contract which closes the valve and opens the pulmonary semilunar valve and pushes O2 poor blood out of the right ventricle through the pulmonary semilunar valve where it becomes part of the pulmonary circuit, ventricle relax causing the pulmonary semilunar valve to close so the blood doesn't flow back into the right ventricle, blood goes to the lungs

left side of the heart

O2 rich blood enters the left atrium from the left pulmonary veins which just came from the lungs where they pick up oxygen, atria contract causing O2 rich blood to travel from left atrium to the left ventricle though the av bicuspid valve also called the mitral valve, ventricles contract which closes the av bicuspid valve and opens the semilunar valve where blood becomes part of the systemic circuit, ventricle relax causing the aortic semilunar valve to close so the blood doesn't flow back into the left ventricle

systemic circuit

O2 rich blood enters the systemic circuit as it exits the heart via the aortic semilunar valve, the first artery of the systemic circuit is the ascending aorta, the ascending aorta artery turns into the aortic arch which has 3 branches which are brachiocephalic artery, left common artery carotid artery, and left subclavian artery, following the aortic arch and its branches is the decending aorta, descending artery carries O2 rich blood to trunk and lower limb body tissue, O2 poor blood high in CO2 leaves the body tissures and returns to the right atrium the superior vena cava (vein) and inferior vena cava (vein) deliver the O2 poor blood to the right atrium of the heart

right and left atrium

are superior to the ventricles, ineffective pumps

oxygen rich blood exits the left ventricle through the _____ and goes to deliver oxygenated blood to the bodys tissues

ascending aorta

aortic sinuses

at the base of the ascending aorta, sacs that prevent the aortic semilunar valve cusps from sticking to the aorta, are the origin of right and left coronary arteries

valves of the heart

atrioventricular valves, semilunar valves

left atrium

blood flows here through the pulmonary veins

right atrium

blood flows here through the superior and inferior vena cava veins

right and left ventricle

both are inferior aspect of heart below the atria, effective pumps/ discharge chambers, force blood into large arteries that emerge from the base of the heart

branches of the aorta in the order they occur

brachiocephalic artery, common left artery, left subclavian artery

pulmonary trunk

branches into right and left pulmonary arteries, receives O2 poor blood from right ventricle; beginning of pulmonary circuit, sends O2 poor blood to lungs to get O2

pulmonary veins

bring oxygen rich blood back from the lungs through the pulmonary circuit, bring O2 rich blood to the left atrium from the lungs

superior and inferior vena cava veins

bring poorly oxygenated blood back from the tissues by the systemic circuit

left common carotid artery

carries O2 rich blood to the neck

subclavian artery

carries O2 rich blood to the upper limbs

brachiocephalic artery

carry O2 rich blood to the head

arteries

carry blood away from the heart

veins

carry blood to the heart

papillary muscles

conical muscular projections from inner surface wall of ventricles, pull the chordae tendineae which tug on av valves to keep them closed during ventricular contractions

endocardium

covers inner surfaces of heart, includes heart valves; simple squamous epithelium

sucli

deep groove

coronary sulcus

deep groove that divides the atria and ventricles, 1 located on anterior aspect of heart the other on posterior aspect

atrioventricular valve

enforce one way blood flow thru heart chambers

visceral pericardium

epicardium inner layer of pericardium, thin layer tightly attached to surface of heart muscle

arch of aorta

has 3 branches the order they exit fro the arch of aorta is brachiocephalic trunk, left common carotid artery and left subclavian artery

fossa ovalis

in adult heart; small, shallow depression left in adult heart after closure of foramen ovale; prevents blood flow from right to left atrium after birth b/c lungs are developed

foramen ovale

in fetal heart only oval opening penetrates interartrial septum and connects the two atria in a fetal hear; closes at birth

left ventricle muscle

is larger, thicker and generates more power

how blood travels through the heart

it enters through the superior and inferior vena cava into the the right atrium goes though the tricuspid valve into right ventricle to the pulmonary semilunar valve into the pulmonary trunk to the lungs comes back through the pulmonary vein into the left atrium through the bicuspid valve to the left ventricle through aortic semilunar valve to the aorta and out to the body

trabeculae carnae

muscular ridges on internal surface of ventricles, an internal network that coordinates contractions of cardiac muscle cells, includes moderator band in the right ventricle only

myocardium

muscular wall of heart; heart wall consists of cardiac muscle, reinforced internally by dense fibrous connective tissue network; contains: atria and ventricles, muscle tissue, blood bessels and nerves; concentric layers of cardiac muscle tissue

heart

name for the cardiac muscle

capillaries

networks between arteries and veins, also called exchange vessels

av valves

openings that connect atrium to ventricles, have fibrous flaps ( also called cusps) flaps are part of the valve, close when ventricles contract

parietal pericardium

outer layer, forms inner layer of pericardial sac, fuses with fibrous tissue

semilunar valves

prevent backflow from vessels that exit heart after the blood is pushed out of the ventricles into the vessels

pectinate muscles

prominent muscular ridges on inner surface of auricle and anterior atrial wall

poorly oxygenated blood exits the right ventricle through the _____ and goes to the lungs to receive oxygen

pulmonary trunk

vessels that return blood to the heart from the pulmonary circuit and the chamber

pulmonary veins, left atrium

ascending aorta

receives O2 rich blood from the left ventricle, is the beginning of the systemic circuit, sends oxygenated blood to all systemic arteries of the body to supply body tissues becomes arch of aorta

________ventricle has a moderator band

right

chambers of the heart

right and left atrium, right and left ventricle

left ventricle is ______

round

interventricular sulci

shallower than the coronary sulcus; separate right and left ventricles; there are 2 interventricular sulci; 1 is anterior interventicular sulcus on anterior surface of the heart and the 2nd is the posterior interventricular sulcus located on the posterior surface of the heart, contain blood vessels that supply oxygen to the heart

the vessels that return blood to the heart from the systemic circuit and the chamber

superior and inferior vena cava, right atrium

chordae tendineae

tiny whit collagenic cords made of connective tissue fibers along the free edge of each cusp of valves, anchor cusps of av valves to ventricle walls to prevent backflow of blood into atrium from ventricles during ventricular contraction

bicuspid valve

valve b/n left atrium and ventricle

aortic semilunar valve

valve b/n left ventricle and ascending aorta artery

tricuspid valve

valve b/n right atrium and ventricle

pulmonary semilunar valve

valve b/n right ventricle and pulmonary trunk/pulmonary arteries

superior vena cava and inferior vena cava

veins (because they carry blood to the heart) bring O2 poor blood from the bodies tissues to the right atrium

epicardium

visceral pericardium that covers heart, serous membrane

right ventricle

wall is thinner and develops less psi than left ventricle, it is pouch shaped