exph 386 exam 4
Function of superior vena cava
It carries deoxygenated blood from above the diaphragm towards the heart.
Where does oxygenated blood empty?
left atrium
Which of the following is correct regarding the flow of blood in reference to the left side of the heart?
Blood flows from the left atrium, through the bicuspid valve, into the left ventricle, through the aortic semilunar valve, and then into the aortic arch.
Which of the following is correct regarding blood flow in reference to the right side of the heart?
Blood flows from the right atrium through the tricuspid valve, into the right ventricle, through the pulmonary semilunar valve, into the pulmonary trunk, and then into the pulmonary arteries.
What is systole?
Contraction of the heart
Function of arteries
carry blood away from the heart
function of veins
carry blood back to the heart
function of the pulmonary veins
carry oxygenated blood from the lungs to the left atrium
The right ventricle is the chamber of the heart that pumps blood for the pulmonary circulation. Based on this information, blood from the right ventricle is on its way to the __________.
lungs
What is a constricted arteriole?
mostly smooth muscle, not completely occluded
function of valves
open during muscular contraction and close when blood begins to back flow
function of mitral (bicuspid) valve
separates the left atrium from the left ventricle
function of the septum
separates the right/ left atria of the heart and the right/left ventricles of the heart
What is diastole
the relaxtion of the heart
Why does the heart pump blood to the lungs through the pulmonary circulation?
to oxygenate blood and discard CO2 through diffusion
what are the atrioventricular valves?
tricuspid and bicuspid (mitral) valves
what is systole?
when the heart contracts and pushes blood out towards the systemic and pulmonary circulation
What is diastole?
when the heart is relaxed and filling with blood
Blood flows in the following sequence in the heart: Superior vena cava/Inferior vena cava, right atrium, tricuspid valve, right ventricle, pulmonic valve, pulmonary artery, lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic valve, aorta
True
The bicuspid valve is located on the left side of the heart
True
There are four chambers in the heart
True
What are the three keys functions of the cardiovascular system?
- deliver oxygen and nutrients to the active tissues -returns deoxygenated blood to the lungs to pick up oxygen -transports heat
What is the lub sound?
-1st heart sound -the tricuspid and mitral valve shutting
What is the dub sound?
-2nd heart sound -the pulmonary and AV valve shutting
What is the vasculature of the heart?
-Aorta -arteries -Arterioles -capillaries -venules -veins
What are varicose veins?
-blood gathers in veins and they become distended and painful -phlebitis occurs from venous walls being inflammed and deteriorating -exercise can help
what is ventricular systole?
-electrical signal arrives in the ventricle -generates contraction -increases ventricular pressure -closes all valves
what is artial systole?
-electrical signal tells the atria to contract -increase of pressure in the atria -blood goes through the AV valve to the ventricle -decrease atria volume
physiological hypertrophy
-enlargement of the heart -pregnancy -reversible, expected, normal -increase in blood volume
pathiological hypertrophy
-enlargment of the heart -can cause death -due to stress -heart failure
What are arteries?
-high pressure -thick walled -conducts oxygenated blood -have smooth muscle cells and endothelial cells
During exercise when are dormant capillaries open?
-increase in pressure -local metabolites -dilated arteriole
distribution of blood at rest percentages
-lungs: 10-12% -heart: 8-11% -systemic artery: 10-12% -capillaries: 4-5% -systemic veins: 60-70%
What is venous pooling?
-may induce fainting from insufficient cerebral blood supply -cooldown can help prevent this
What does left ventricular mass show?
-predicts overall cardiac health -increases in age -peaks around ages 20-30 -predicts different pathologies
what is ejection phase?
-pressure exceeds the aortic /pulmonary valve pressure -valves open and blood leaves the ventricles -ventricular volume goes down -pressure comes back down -semilunar valves close
What are capillaries?
-single layer of endothelial cells -diameter is reduced so that only one blood cell can pass through -at rest only some capillaries are open
What are venules?
-small veins -collect deoxygenated blood from capillaries
What are arterioles?
-smaller branched arteries -constrict or relax changing resistance to blood flow -known as resistance cells
What is cardiac atrophy?
-smaller heart -comas -cancer
What are veins?
-thin walled -lower pressure -some smooth muscle and endothelial cells
Structure of an artery (3 parts)
-tunica intimia: endothelial cells, endothelium -tunica media: smooth muscle cells and elatin -tunica externa: collagen, elastin, connective fibers
What are veins?
-venules -veins -capacitance veins
How many valves are in the heart?
4 valves
what is passive filling?
70% of the blood flows passively into the ventricles before the atria contract
What part of the heart delivers richly oxygenated blood to the body?
Aorta
Trace the pathway of a red blood cell which starts in the right atrium and ends in the brain
Beginning in the right atrium, the red blood cell (RBC) will travel through the tricuspid valve to enter into the right ventricle. From there it will travel through the pulmonary valve to the pulmonary circuit via the pulmonary artery. (The pulmonary valve can also be referred to as the right semilunar valve) The pulmonary artery brings deoxygenated blood from the right side of the heart to the lungs where it can get oxidized. From the lungs, oxidized blood travels towards the left atrium via the pulmonary vein. From the left atrium, the RBC will travel through the mitral valve to enter the left ventricle. From the left ventricle the RBC will move through the aortic valve (which can also be referred to as the left semilunar valve) into the aorta. From the aorta the RBC will travel towards the brain via several arteries. -The RBC will take the following route: right atrium, tricuspid valve, right ventricle, pulmonary valve, pulmonary artery, lung, pulmonary vein, left atrium, mitral valve, left ventricle, aortic valve, aorta, brain.
What is stroke volume?
EDV-ESV -how much blood is ejected from the heart
The atriums are located below the ventricles
False
Pulmonary veins take unoxygenated blood away from the heart
False The pulmonary artery takes unoxygenated blood away from the heart to the lungs to become oxygenated and then back through the pulmonary vein.
What part of the heart delivers unoxygenated blood to the lungs?
Pulmonary artery The pulmonary artery delivers unoxygenated blood to the lungs and then it's taken through the pulmonary VEINS back to the heart.
What part of the heart delivers oxygenated blood to the heart?
Pulmonary vein
On the right side of the heart, blood flows from the right ventricle to the?
Pulmonic valve to the pulmonary artery
From the following is found on the right and left side of the heart - tricuspid valve - pulmonary artery - superior vena cava - mitral valve - aorta - pulmonary vein
RIGHT: - tricuspid valve - pulmonary artery - superior vena cava LEFT: - tricuspid valve - pulmonary artery - superior vena cava
What is active filling?
The remainder of blood enters the ventricle as the atria contracts
myocardium
Thick middle muscle layer of the heart, contractile cells
What are the four chambers of the heart?
Upper: right and left atrium Lower: right and left ventricle
What are capacitance veins?
acts as a blood reservoir that can be called on for exercise
function of pulmonary veins
carries oxygenated blood from the lungs to the heart
Which of the following is also known as the mitral valve?
bicuspid valve
What is isovolumetric relaxation?
brief period of time when all the heart valves are closed, the ventricular pressure decreases but the volume remains the same
What is isovolumetric contraction?
brief period of time when all the valves are closed, ventricular pressure increases, but volume does not change
Function of the pulmonary artery
carries deoxygenated blood from the right ventricle to the lungs.
What is a closed precapillary sphincter?
closed, will occlude, blood will not go in at rest
What are the chordinae tendinae?
connect to the papillary muscle, as it contracts the papillary muscle to pull down which closes the valves
Heart wall components
endocardium, myocardium, epicardium
Which of the following choices shows the layers of the heart from the innermost layer to the outermost layer?
endocardium, myocardium, pericardium
Endocardium
inner lining of the heart
Which of the following statement is the major function of the aorta?
it brings oxygenated blood to the body tissues
epicardium
outermost layer of the heart -helps heart not rub on the lungs -surrounds the heart
Function of tricuspid valve
prevent back flow of blood into the right atrium from the right ventricle, separates the right atrium from the right ventricle
function of the pulmonary semilunar valve
prevents blood from an artery from flowing back into the right ventricle
Function of aortic semilunar valve
prevents blood in the aorta from flowing backwards into the left ventricle
The heart contracts twice for every heartbeat. One contraction is the atrial contraction while the other is the ventricular contraction. During ventricular contraction, which two valves of the heart open?
pulmonary and aortic valve
What are the semilunar valves?
pulmonary and aortic valves -these eject blood out of the heart
The blood enters on the left side of the heart through the ______________ and enters the left atrium. It then passes through the _____________to enter the left ventricle.
pulmonary vein, bicuspid valve The blood enters on the left side of the heart through the PULMONARY VEIN and enters the left atrium. It then passes through the BICUSPID VALVE to enter the left ventricle.
function of the inferior vena cava
returns blood from body regions below the diaphragm back to the heart
where does deoxygenated blood empty?
right atrium
What are the two types of blood flow circuits?
systemic: heart and systemic -carries oxygenated blood away from the heart to the body and then returns oxygenated blood back to the heart pulmonary: heart and lungs -carries deoxygenated blood away from the heart, to the lungs, returns oxygenated blood to the heart
What is end systolic volume (ESV)?
the amount of blood in the ventricle after contraction
What is end diastolic volume?
the amount of blood in the ventricle before contraction
Although the skier has a jacket on, she is still cold. How can her circulatory system help keep her warm?
the arterioles of the surface of her skin can vasoconstrict so less heat can leave her body
Which of the following actions creates the "lub-dub" sound he hears?
the closing of the valves