Test 2 AP2 Lect Flashcards
What does the systemic circulation deliver?
Delivers O2 to all body cells and carries away wastes
What is the function of the pulmonary circuit?
Eliminates CO2 via the lungs and oxygenates the blood
What is the avg. size of the heart?
14cm long, 9cm wide
The cardiac myocyte generates ATP thru?
Cellular repsiration (need constant supply of O2)
What is myocardial infarcation?
Heart attack - heart does not have sufficient blood supply
Where is the heart located?
Posterior to the sternum, base lies beneath 2nd rib, apex @ 5th intercostal, lies upon diaphragm
What are the 3 layers of the heart?
Endocardium (innermost), myocardial (middle), epicardium (outermost)
The epicardium is continous with which membrane?
Visceral layer of serous pericardium
Function of the epicardium?
Forms a protective outer covering, secretes serous fluid
Function of the myocardium
Contracts to pump blood from the heart chambers
Function of the endocardium
Forms a protective inner lining of the chamber and valves
What are veins?
Blood vessels (b.v) that carry blood towards the heart
What are arteries?
B.V that carries blood AWAY from the heart
The right atrium receives blood from the?
Inferior vena cava (IVA), superior vena cava (SVA), and coronary sinus
What are the three sections of the coronary sinus?
(1) Great cardiac vein (2) Middle cardiac vein (3)Small cardiac vein
The coronary sinus gets their drainage from?
From the coronary circulation and then goes to the RA (right atrium)
How does blood flow from the heart to the lungs?
Vena cava –> right atrium –> tricupside valve –> right ventricle –> semilunar pulmonary valve –> pulmonary trunk –> lungs (r. pulmonary artery & l. pulmonary artery)
Where does the right ventricle receive its blood from?
Right atrium
What valve is between the right atrium and the right ventricle?
Tricupsid valve
The right ventricle carries blood to the
Semilunar pulmonary valve –> pulmonary trunk –> lungs (right pulmonary artery & left pulmonary artery)
How much blood does the right atrium receive?
70% of blood flow
What happens when the ventricles relax?
Chambers of the ventricles are filled with blood
What happens to the ventricles after it relaxes?
The chambers of the ventricles contracts and push the blood UP
The left atrium receives blood from the
Pulmonary veins
Are pulmonary veins deoxygenated or oxygenated?
Oxygenated
The blood from the left atrium has to pass through which valve to get to the left ventricle?
Bicupsid/Mitral valve
The left ventricle receives its blood from
The left atrium
The left ventricle carries oxygenated blood to the
Aortic Semilunar valve –> aorta –> body
Steps of blood flow from the heart to the body
pulmonary veins -> Left atrium -> bicupsid valve -> left ventricle (L.V) -> aortic semilunar valve -> aorta
What is the function of the tricupsid valve?
Prevent backflow of blood from the right ventricle to the right atrium during ventricular contraction
What is the function of the pulmonary valve?
Prevents blood from moving from teh pulmonary trun into right ventricle during ventricular relaxation
What is the funtion of the mitral valve?
Prevents backflow of blood from the L.V into the L.A during ventricular contraction
What is the function of the aortic valve?
Prevents blood frmo moving from aorta into L.V during ventricular relaxation
“Lubb”
Sound is due to the closure of atrial valve (tricupsid & mitral valve)
“Dubb”
Sound due to the closure of aortic semilunar valve
What is the chordae tendinae?
aka heart strings - Connective tissue that connects papillary muscles to the tricupsid and mitrial (bicupsid) valves
Function of the fibrous skeleton of the heart
Separates and allows the atrium to contract but the ventricles do not contract at the same time as the atriums
How can we prevent backfrom of blood?
Papillary muscle will contract first before the rest of the muscle in the ventricular contraction
What is the normal blood pressure of an individual?
120ml of mercury/80mL of mercruy
What is systole?
After ventrical contraction
What is diastole?
Heart relaxation (pressure found in teh aorta)
What happens when the heart relaxes?
Chambers open up (pressure drops so the blood in the aorta can gush back in)
What is isovolumetric contraction?
“iso” = same Volume of blood does not change but the heart is still contracting. (doesn’t change because the heart is pressuraizing)
What is Boyle’s Law?
Pressure is inversley proportional to volume (e.g if you want pressure to increase, decrease the volume)
What happens if there is a defect in the intraventricular septum?
Septal defect - a hole in the lower chambers of the wall (blood flows from the L.V to the R.V)
What must the intraventricular pressure be if a person has hypertension (BP 140/90)?
Intraventricular pressure has to be higher than 90mL of mercury
Why is it bad if the intraventricular pressure is high?
Because it’s asking the heart to work harder to generate intraventricular pressure above the DIASTOLIC pressure to push blood out.
Chronic hypertension leads to
Left ventricle wall gets thicker in order to generate higher pressure which leads to HEART FAILURE
