BIO 204 Module 2 quiz
Signals leave the AV node and descend along this structure toward the apex:
AV bundle
What is the function of gap junctions?
Allow cardiomyocytes to electrically stimulate neighbors
Alternative routes of blood supply are called ______.
Anastomoses
What is unique to fenestrated capillaries?
Filtration pores
The _____ valve regulates the flow of blood between the right ventricle and the vessels leading to the lungs.
Pulmonary
Which of the following belong to the pulmonary circuit?
Pulmonary arteries and pulmonary veins
Distributes the electrical excitation to the ventricles:
Purkinje fibers
Oxygen-poor blood passes through the _________.
Right AV (tricuspid) and pulmonary valves
During isovolumetric contraction, the pressure in the ventricles _______.
Rises rapidly
The pacemaker that determines the heart rate:
Sinoatrial (SA) node
The plateau in the action potential of cardiac muscle results from the action of ______.
Slow Ca2+ channels
Which of the following is not part of the cardiac conduction system?
Tendinous cords
TorF: The pulmonary circuit is supplied by both the R and L side of the heart.
false (only the right)
Atrial systole begins _____.
immediately after the P wave
What layer of the heart is the thickest; made of muscles; and performs the work of the heart?
Myocardium
The electrical gateway to the ventricles:
Atrioventricular (AV) node
When does ventricular depolarization being?
Begins at the apex and progress superiorly as the atria repolarizes
What is the most important force driving reabsorption at the venous end of a capillary?
Blood colloid osmotic pressure
The long plateau in the action potential observed in cardiomyocytes is probably related w/ ______ staying longer in the cytosol.
Ca 2+
The volume of blood ejected by each ventricle in one minute is called the ______.
Cardiac output
Blood order starting from systemic circuit:
Conducting arteries Distributing arteries Resistance arteries Arterioles Capillaries Post-capillary venules Muscular venules medium veins venous sinuses large veins
How would blood pass through the vessels in order starting with entering the systemic circuit?
Conducting arteries disturbing arteries resistance arteries arterioles capillaries
What makes up intercalated discs?
Desmosomes, gap junctions, fascia adherens
What layer of the heart covers the valve surfaces and is continuous w/ the endothelium of the blood vessels?
Endocardium
What layer of the heart is the serous membrane; mainly simple squamous epithelium over areolar connective tissue w/ an adipose covering?
Epicardium
TorF: Blood in the heart chambers provides most of the myocardium's oxygen and nutrient needs.
False
TorF: Desmosomes form channels that allow each cardiomyocyte to electrically stimulate its neighbor.
False
TorF: Large veins, medium veins, and venules have valves to prevent the backflow of blood.
False
Which vessels have the thickest tunica media?
Large arteries
Which of the following is a feature shared by cardiac muscle and skeletal muscle?
Muscle fibers striations
The _____ performs the work of the heart.
Myocardium
Atrial depolarization causes the _____.
P wave
Which of the following is the most superficial layer enclosing the heart?
Parietal layer of the serous pericardium
Blood usually passes through one network of capillaries from the time it leaves the heart until the time it returns; but there are exceptions, notably the ______.
Portal systems and anastomoses
Opening and closing of the heart valves is caused by _____.
Pressure gradients
What is the function of desmosomes?
Prevent cardiomyocytes from pulling away when they contract
TorF: Cardiac muscle is not prone to fatigue b/c it makes a little use of anaerobic fermentation or the oxygen debt mechanism.
True
TorF: if the SA node is damaged, nodal rhythm is sufficient to sustain life.
True
What is unique to continuous capillaries?
pericytes, tight junctions, pinocytic vesicles
What are the functions of intercalated discs?
thick connections between the cardiomyocytes that are the mechanical and electrical link for cells