Chapter 11 Review Flashcards
Tricupsid valve
Located between the right atrium and right ventricle. Closes to prevent back flow into the right atrium during ventricular contraction.
Bicupsid valve
Located between the left atrium and left ventricle. Closed during ventricular contraction to prevent back flow into the left atrium.
Pulmonary semilunar valve
Located between the right ventricle and the pulmonary artery. Closes to prevent back flow into the right ventricle during ventricular relaxation. When the ventricles relax, blood flows backward in the pulmonary artery pushing the semilunar valve doors closed.
Aortic valve
Located between the left ventricle and the aorta. Opens when the ventricles contract to allow oxygenated blood flow to the body. Closes when ventricles relax to prevent back flow in the left ventricle.
What is the difference between the pulmonary and systemic circulations?
Pulmonary: moves blood between the heart and the lungs.
It transports deoxygenated blood to the lungs to absorb oxygen and release carbon dioxide. The oxygenated blood then flows back to the heart.
Systemic: moves blood between the heart and the rest of the body.
How do the structural differences between the ventricles relate to the function of the ventricles?
The myocardial tissue is thicker on the left ventricle as this side must contract to push blood to all regions of the body. The myocardial tissue on the right is thinner as contraction only needs to move blood to the lungs.
How are the great vessels able to bring nutrients to tissues despite being large?
Arteries connect to arterioles. Arterioles connect with even smaller blood vessels called capillaries. Through the thin walls of the capillaries, oxygen, and nutrients pass from the blood into tissues, and waste products pass from tissues into blood. From the capillaries, blood passes into venules, then into veins to return to the heart.
What are the main structural differences between veins and arteries?
Veins carry blood toward the heart
Arteries carry oxygen away from the heart
Arteries are often described as vessels that carry oxygen-rich blood, and veins are said to carry oxygen-poor (carbon-dioxide rich) blood. What are 2 sets of exceptions to this rule that were discussed in this chapter?
Pulmonary artery carries deoxygenated blood away from the heart towards the lungs. The pulmonary veins carry oxygenated blood from the lungs to the left atrium
What structure feeds the heart tissue itself with oxygen, and is a landmark to identify the anterior heart in dissection?
Coronary arteries
During the cardiac cycle, when are the AV valves open?
During mid to late diastole, heart is completed relaxed
and blood flowing passively into and through the atria into the ventricles.
During the cardiac cycle, when are the AV valves closed?
During ventricular systole, pressure within the ventricles increase rapidly, closing the av valves.
During the cardiac cycle, when are the Semilunar valves open?
Ventricular systole, when the intraventricular pressure is higher than the pressure in the large arteries leaving hte heart (pulmonary trunk or aorta) the semilunar valves are forced open.
During the cardiac cycle, when are the Semilunar valves closed?
During all of diastole while blood filled the atria and ventricles.
What is responsible for the ¨lub-dub¨ sounds? Which is louder? Which is longer?
This sound comes from the valves shutting on the blood inside the heart. The first sound (the lub) happens when the mitral and tricuspid valves close. The next sound (the dub) happens when the aortic and pulmonary valves close after the blood has been squeezed out of the heart.
After a bout with bacterial endocarditis, scar tissue often stiffens the edges of the heart valves. How would this be picked up in a routine examination?
Low QRS wave
Systole
Measures the amount of pressure that blood exerts on arteries when ventricles are contracted
Diastole
Measures the pressure when the ventricles are relaxed.
What is the intrinsic conduction system? How does it work?
Step 1; stimulation of the sinatrial node
step #2: stimulation of the atrioventricular node
Step #3: propagation to the Av bundle of His
Step #4: Splitting into the bundle branches
Step #5:Propagation up the purkinje fibers
What are the layers of the heart covering and heart wall?
Endocardium - outermost
Myocardium - middle (M)
Epicardium - innermost
Pericardial cavity - middle space
Epicardium - visceral layer of serous pericardium
Fibrous pericardium - outermost
What structure divides the left from the right ventricle?
Interventricular septum
What is the difference between bradycardia and tachycardia?
Bradycardia: slow heartbeat with resting heart rate>60 beats a minute.
Tachycardia: fast heart with resting heart rate<100 beats a minute.
SA node
pacemaker of the heart
is a specialized myocardial structure that initiates the electrical impulses to stimulate contraction
is found in the atrial wall at the junction of superior caval vein and the right atrium
Internodal pathway
the connecting pathways that form a direct connection between the sinoatrial node and the atrioventricular node in the right atrium of the heart.
AV bundle (bundle of His)
is an elongated segment connecting the AV Node and the left and right bundle branches of the septal crest
Bundle branches
Two bundle branches carry the electrical signal to the bottom of the heart and cause the ventricles to beat. These are termed the right bundle and left bundle.
Purkinje fibers
are networks of fibers that receive conductive signals originating at the atrioventricular node (AVN), and simultaneously activate the left and right ventricles by directly stimulating the ventricular myocardium.
Electrocardiogram (EKG)
is a test that detects and records the strength and timing of the electrical activity in your heart.
This information is recorded on a graph that shows each phase of the electrical signal as it travels through your heart.
Which type of vessel would have the highest blood pressure? Why?
Large arteries like the aorta because blood moves through them when the heart is contacting
