BIOS 255- Week 2 - The Cardiovascular System (Heart) Practice Solution Manual Latest Update 2025
Which of the following membranes are found in the body cavities and have parietal layers that line the
cavities and visceral layers that cover the organs? - Answers serous membrane
Which is true of cardiac muscle tissue? - Answers striated, uninucleated, intercalated discs
Epicardium characteristics & function - Answers - outermost layer
- composed of elastic fibers & adipose tissue
- produces pericardial fluid
Myocardium characteristics & function - Answers - middle layer
- composed primary of cardiac muscle
- generates force to pump blood
Endocardium characteristics & function - Answers - innermost layer
- regulates contractility
Which chamber of the heart has the thickest myocardium? - Answers left ventricle
Which valve separates the right atrium and the right ventricle? - Answers tricuspid valve
Which valve separates the left atrium and the left ventricle? - Answers bicuspid (mitral) valve
Which valve separates the heart from the vessel that delivers blood to the lungs to receive oxygen? -
Answers pulmonary valve
Which valve separates the heart from the vessel that delivers blood to the entire body? - Answers aortic
valve
Which valve is between the right ventricle and pulmonary trunk? - Answers pulmonary semilunar valve
Which valve is between the left ventricle and ascending aorta? - Answers aortic semilunar valve
What is the region of the thoracic cavity where the heart is located? - Answers mediastinum
, Which type of cell junction allows cardiac muscle tissue to transmit signals rapidly? - Answers gap
junctions
Which of the following are functions of the pericardium? - Answers - prevents the heart from bouncing
in the thoracic cavity.
- prevents the heart from overfilling with blood
- creates a near-frictionless environment through the production of serous fluid.
Which elements are required to sustain a muscular contraction? - Answers - calcium
- sodium
- potassium
- ATP
What term is given to the event whereby the voltage of an action potential begins to return to its resting
potential from the height of its peak? - Answers repolarization
What term is given to the event whereby another action potential cannot be propagated shortly after an
action potential? - Answers refractory period
Cardiac _________ action potentials will have a rapid depolarization that is maintained via the presence
of calcium. - Answers contractile
Cardiac _________ action potentials will have both a rapid depolarization and repolarization with no
refractory period. - Answers autorhythmic
The ____________ phase of the action potential in cardiac muscle delays repolarization to the resting
membrane potential in order to lengthen refractory period. - Answers plateau
Without a plateau, extending the refractory period, cardiac muscle cells might be stimulated so quickly
that they would not relax, leading to a sustained contraction known as what? - Answers tetany
A distinct, extended plateau occurs in the action potential in cardiac muscle cells, producing a refractory
period of ______ milliseconds. - Answers 250
Which of the following aspects of the conduction system would directly result in contraction of the
myocardium in the ventricular walls? - Answers purkinje fibers
During the depolarization phase of cardiac muscle ______________. - Answers voltage-gated sodium
channels open
Which of the following membranes are found in the body cavities and have parietal layers that line the
cavities and visceral layers that cover the organs? - Answers serous membrane
Which is true of cardiac muscle tissue? - Answers striated, uninucleated, intercalated discs
Epicardium characteristics & function - Answers - outermost layer
- composed of elastic fibers & adipose tissue
- produces pericardial fluid
Myocardium characteristics & function - Answers - middle layer
- composed primary of cardiac muscle
- generates force to pump blood
Endocardium characteristics & function - Answers - innermost layer
- regulates contractility
Which chamber of the heart has the thickest myocardium? - Answers left ventricle
Which valve separates the right atrium and the right ventricle? - Answers tricuspid valve
Which valve separates the left atrium and the left ventricle? - Answers bicuspid (mitral) valve
Which valve separates the heart from the vessel that delivers blood to the lungs to receive oxygen? -
Answers pulmonary valve
Which valve separates the heart from the vessel that delivers blood to the entire body? - Answers aortic
valve
Which valve is between the right ventricle and pulmonary trunk? - Answers pulmonary semilunar valve
Which valve is between the left ventricle and ascending aorta? - Answers aortic semilunar valve
What is the region of the thoracic cavity where the heart is located? - Answers mediastinum
, Which type of cell junction allows cardiac muscle tissue to transmit signals rapidly? - Answers gap
junctions
Which of the following are functions of the pericardium? - Answers - prevents the heart from bouncing
in the thoracic cavity.
- prevents the heart from overfilling with blood
- creates a near-frictionless environment through the production of serous fluid.
Which elements are required to sustain a muscular contraction? - Answers - calcium
- sodium
- potassium
- ATP
What term is given to the event whereby the voltage of an action potential begins to return to its resting
potential from the height of its peak? - Answers repolarization
What term is given to the event whereby another action potential cannot be propagated shortly after an
action potential? - Answers refractory period
Cardiac _________ action potentials will have a rapid depolarization that is maintained via the presence
of calcium. - Answers contractile
Cardiac _________ action potentials will have both a rapid depolarization and repolarization with no
refractory period. - Answers autorhythmic
The ____________ phase of the action potential in cardiac muscle delays repolarization to the resting
membrane potential in order to lengthen refractory period. - Answers plateau
Without a plateau, extending the refractory period, cardiac muscle cells might be stimulated so quickly
that they would not relax, leading to a sustained contraction known as what? - Answers tetany
A distinct, extended plateau occurs in the action potential in cardiac muscle cells, producing a refractory
period of ______ milliseconds. - Answers 250
Which of the following aspects of the conduction system would directly result in contraction of the
myocardium in the ventricular walls? - Answers purkinje fibers
During the depolarization phase of cardiac muscle ______________. - Answers voltage-gated sodium
channels open
