A&P2 Chapter 20
The principle that increasing the end-diastolic volume results in a corresponding increase in the stroke volume is known as...
Frank-Starling principle
the ear-like extension of the atrium is the...
auricle
The property of heart muscle to contract in the absence of neural or hormonal stimulation is called...
automaticity
A slower-than-normal heart rate is called..
bradycardia
The long plateau phase of the cardiac muscle action potential is due to..
calcium channels remaining open
the function of the atrium is to..
collect blood and then pump it to the ventricle
The structures responsible for distributing excitation to the contractile cells are...
conducting cells
If the force of ventricular contraction increases, what will happen to the end-systolic volume?
decrease
The relaxation phase of the cardiac cycle is called...
diastole
the structure that permits blood flow from the right atrium to the left atrium in the fetal circulation is the...
foramen ovale
Which statement correctly describes the term left atrioventricular valve?
its cusps open into the left ventricle
Which valve(s) contains 2 cusps?
left AV valve
The muscle layer of the heart is the...
myocardium
Prominent muscular ridges in the anterior atrial wall and auricles are called...
pectinate muscles
the ____ circuit carries blood to and from the lungs.
pulmonary circuit
The normal pacemaker of the heart is located in..
sinoatrial node
The ________ circuit carries blood from the aorta to the right atrium.
systemic circuit
The contraction phase of the cardiac cycle is called...
systole
Beginning with the right atrium, what is the order of the valves through which blood will pass?
tricuspid valve, pulmonary semilunar valve, mitral valve, aortic valve
what is the correct order of the structural components of the conducting system of the heart?
1. SA node 2. AV node 3. AV bundle 4. Bundle branches 5. Purkinje fibers
What is the correct order for the flow of blood entering from the systemic circulation?
1. vena cavea 2. right atrium 3. right ventricle 4. pulmonary trunk 5. pulmonary veins 6. left atrium 7. left ventricle 8. aorta
Considering the left ventricle, why does isovolumetric ventricular contraction occur during ventricular systole?
Aortic pressure is higher than ventricular pressure and the ventricle must pressurize the blood to open the aortic valve.
