Lecture 16 and 17 Flashcards
Describe the characteristics of the heart
generates blood pressure through alternate cycles of the heart wall’s contraction and relaxation.
• Blood flow through the heart is unidirectional because of four
valves within the heart
Describe pulmonary circulation
right side of the heart and the pulmonary arteries and veins;
conveys blood to the lungs and back to the left side of the heart
Describe systemic circulation
left side of the heart and arteries and veins; conveys blood to most body tissues and back to the right side of the heart
Describe the position of the heart
Slightly left of midline deep
to the sternum in a compartment of the thorax known as the mediastinum
More positions of the heart info
The posterosuperior surface of the heart is mainly the left
atrium and is called the base of the heart.
• The superior border is formed by the great arterial vessels
and the superior vena cava.
• The inferior conical end is called the apex.
• The inferior border is formed by the right ventricle.
Describe structure of the pericardum
a tough sack that encloses the heart
composed of fibrous pericardium, serous pericardium
Describe fibrous pericardium
outer covering of tough, dense
connective tissue
Describe serous pericardium
parietal layer
visceral layer
describe parietal layer
lines the inner surface of the fibrous pericardium
describe visceral layer
covers the outer surface of the heart
Function of pericardium
• Restricts heart movements
so that it moves only slightly
within the thorax
What are the 3 layers of the heart wall
Epicardium
Myocardium
Endocardium
Describe Epicardium
consists of the visceral layer of the serous pericardium and areolar connective tissue
Describe Myocardium
—cardiac muscle; thickest of the three layers
Describe endocardium
internal surface of the heart chambers and external surface of the heart valves; consists of the inner heart lining, endothelium and areolar connective tissue.
Descirbe the externals of the heart
• Composed of four hollow chambers - two smaller and superior atria - two larger inferior ventricles
Describe the internals of the heart(Chambers)
The heart possesses four chambers: • Right atrium • Right ventricle • Left atrium • Left ventricle
Describe the internals of the heart(Valves)
The heart also possesses four valves: • Right atrioventricular (tricuspid) • Pulmonary semilunar • Left atrioventricular (bicuspid or mitral) • Aortic semilunar
Describe right coronary artery
Branches into two arteries:
• Marginal artery
• Posterior interventricular artery
Describe marginal artery
supplies the right border of the heart
Describe Posterior interventricular artery
supplies the posterior surface of the left
and right ventricles
Describe left coronary artery
Branches into two arteries:
Anterior interventricular artery
Circumflex artery
Describe Anterior interventricular artery
also called the left anterior descending
artery, supplies the anterior surface of both ventricles and most of the
interventricular septum