chapter 17 Flashcards
blood vessels that carry blood away from the heart
arteries
blood vessels returning blood to the heart
veins
where is the heart located?
in the mediastinum between the second rib and fifth intercoastal space
double walled sac that encloses the heart
pericardium
epithelial membrane that covers the pericardium
serosa
2 layers of the serosa
parietal layer
visceral layer
major veins of the heart
small cardiac vein
anterior cardiac vein
coronary sinus
great cardiac veins
major arteries of the coronary circulation
right and left coronary artery
marginal artery
circumflex artery
anterior and posterior interventricular artery
which side of the heart is the pump for the pulmonary circuit?
right heart
which side of the heart is the pump for the systemic circuit?
left heart
valves between the atria and ventricles
atrioventricular valves
AV valves
what connects smooth muscle cells and allows for ions to pass freely from cell to cell?
gap junctions
The pathway of blood from the heart to the lungs
Right atrium > tricuspid valve > right ventricle > pulmonary valve > pulmonary trunk > pulmonary arteries > lungs
Pathways of blood from the lungs through the heart
Lungs > pulmonary veins > left atrium > bicuspid valve > left ventricle > aortic valve > aorta > systemic circulation
Describe the cardiac muscle cells
striated, short, fat, branched, and interconnected
3 ion channels of cardiac muscles
- Na+ channels for Na + inflow
- K + channels for K + outflow
- Ca2+ channels for Ca2+ inflow
what triggers the opening of Ca sensitive channels in the SR
Ca influx
where is the tricuspid valve located?
between the right atrium and ventricle
where is the mitral valve located?
between the left atrium and ventricle
to which side of the body is the apex of the heart pointed?
left hip
what marks the exterior boundary between the ventricles?
anterior and posterior interventricular sulcus
cardiac muscle tissue is found in which layer of the heart?
myocardium
valve between the right atrium and ventricle
tricuspid
valve between the left atrium and ventricle
bicuspid or mitral valve
the anterior surface of the heart consists mostly of what chamber?
right ventricle
structure that prevents prolapse of the atrioventricular valves
chordae tendineae
how does oxygenated blood return to the heart?
through the pulmonary veins
where blood goes when it is pumped out of the left ventricle?
aorta
what prevents blood from flowing back into the left ventricle?
aortic semilunar valve
where does deoxygenated blood from the myocardium enter the right atrium through?
the coronary sinus
period of time when atrial repolarization occurs
QRS complex
another name for atrioventricular groove
coronary sulcus
where is 2/3rd of the heart located?
left of the midsternal line
2 layers of the pericardium
parietal and visceral
what covers the pericardium?
the serosa
3 ion channels of cardiac muscle
Ca - calcium
NA - sodium
K - potassium
The epicardium is also what layer of the pericardium?
the visceral layer
tough outer layer surrounding the pericardium
the superficial fibrous pericardium
what is it called when all cardiac muscle cells act as if they are one big cell?
functional syncytium
what is the fibrous skeleton of the heart?
the myocardium
what do cardiac muscle cells have more of compared to skeletal muscle cells?
mitochondria
what causes action potential in cardiac muscle cells
Calcium
what causes repolarization in cardiac muscle cells
inactivation of the Ca channels and opening of voltage gates K+ channels
what is the voltage change during depolarization
-90mV to +30mV
which ventricle has a thicker wall?
the left ventricle
where does the myocardium receive its blood supply from?
coronary arteries
what provides collateral routes for blood delivery to the heart muscle
anastomoses
where are trabeculae carnae found?
in the ventricles
function of auricles
increase volume of the atria
where does the right atria receive blood from?
superior vena cava, inferior vena cava, and the coronary sinus
what cone shaped muscles do both ventricles have?
papillary muscles
what muscles are found in the atria?
pectinate muscles