Chapter 13 Cardiovascular System Flashcards
Distinguish between the visceral pericardium and the parietal pericardium
The visceral pericardium covers the heart and then turns back on itself for an outer covering called the pericardium
Describe the layers of the heart wall
The epicardium protects the heart by reducing friction
The myocardium consists mostly of cardiac muscle tissue
The endocardium contains epithelium and connective tissue.
Name and locate the four chambers of the heart
Right atrium is above the right ventricle the left atrium is above the left ventricle separated by interventricular septum
Describe the function of each heart valve
The tricuspid valve allows blood to move from the right atrium to the right ventricle.
The pulmonary valve allows blood to leave the right ventricle
The mitral valve allows blood to pass from the left atrium to the left ventricle
The aortic valve allows blood to leave the left ventricle
Review the path of blood through the heart
Blood enters the right atrium through the vena cava and coronary sinus then passes through the tricuspid valve and enters the right ventricle then it’s pushes through the pulmonary valve and into the pulmonary trunk
Upon return from the lungs blood enters the left atrium moves through the mitral valve and into the left ventricle and through the aortic valve into the aorta and it’s branches
Which vessel supply blood to the myocardium
Branches of the coronary artery
How does blood return from the cardiac tissues to the right atrium
Through the cardiac vein’s into the coronary sinus
Describe the pressure changes in the atria and ventricles
The atria contract while ventricles relax then ventricles contract while atria relax. Then they both relax
What causes heart sounds
The lubb is from AV valve closing
Dubb is from aortic valve closing
What is a functional syncytium
A mass of merging cells that function as a unit
What type of tissues make up the cardiac conduction system
Specialized cardiac muscle tissue who’s fibers contain only a few myofibrils
How is cardiac impulse initiated
From the SA node or sinoatrial node
How is a cardiac impulse transmitted from the right atrium to the other heart chambers
Sa node Atrial syncytium Junctional fibers AV node AV bundle Bundle branches Purkinje fibers Ventricular syncytium
How do you parasympathetic and sympathetic impulses help control heart rate
Parasympathetic fibers slow heart rate while sympathetic fibers increased heart rate and force of contractions
How do you changes in the body temperature affect heart rate
Rise in body temperature increased rate low body temperature decreases heart rate
Describe the effects on the heart of abnormal concentrations of potassium and calcium ions
Excess potassium decreases the rate and force of contractions. potassium deficiency can cause life-threatening arrhythmia
Excess calcium increases heart action and extended heart contraction, low calcium depresses heart action