Bio 2402 Chapter 19-The Circulatory System: Heart

identify the external structures of the heart

identify the internal structures of the heart

What are the layers of the heart?

pericardium

epicardium

myocardium

endocardium

What is the pericardium?

-a double-walled sac

-Allows heart to beat without friction, provides room to
expand, yet resists excessive expansion

-Anchored to diaphragm inferiorly and sternum anteriorly

What is Fibrous pericardium?

-tough collagenous fibrous sac set off from outermost layer, surrounding the heart but not attached to it.

-attached to the central tendon of the diaphragm below

-roots of the great blood vessels at the top of the heart

What is Serous pericardium?

-simple squamous epithelium overlying a thin layer of elastic tissue

-non-motile cilia that increase the surface area for secretion and absorption of pericardial fluid into the pericardial cavity

What is the parietal layer? /part of serous pericardium/

-At the roots of the great vessels, it turns outward and lines the inside of the fibrous pericardium.

What is the visceral layer (epicardium)? /part of the serous pericardium/

-adheres to heart surface and outermost layer of heart itself

What is the pericardial cavity?

-space between parietal and visceral layers of serous pericardium, filled with 5 to 30 mL of pericardial fluid

What is Epicardium?(visceral layer of serous pericardium)

-outermost layer just described (visceral layer of serous pericardium)

-thin and translucent

-includes a thick layer of adipose tissue that encloses the major coronary blood vessels and protects them from ygcompression