Layers of the Heart Wall

Question 1

What is the innermost layer called?

Answer 1

Endocardium

Question 2

Describe the histological structure of the endocardium (tissue types etc)

Answer 2

in contact with the blood = endothelium (a layer of simple squamous epithelia)
underneath for support = loose irregular FCT

Question 3

What is the purpose of the endothelium?

Answer 3

provides a non-stick surface between the heart wall and the blood to reduce clotting/blockages

Question 4

What layer of the heart is most easily visible?

Answer 4

The myocardium

Question 5

Which ventricle (R or L) has the thickest layer of myocardium?

Answer 5

the L has 3x thicker myocardium because it is sending blood around the body = further and under higher pressure than the R ventricle which sends blood horizontally and a short distance to the lungs

Question 6

What 3 components make up the epicardium?

Answer 6

• blood vessels (arteries and veins)
• loose irregular FCT
• visceral pericardium

Question 7

What is the outermost layer of the pericardium?

Answer 7

Fibrous pericardium

Question 8

What structure is found between the fibrous pericardium and the epicardium?

Answer 8

The serous membrane

Question 9

What is the function of the serous membrane?

Answer 9

Lubricated bag for heart to beat within = reduces friction

Question 10

What is the side of the serous membrane called that is in contact with the heart?

Answer 10

The visceral layer (visceral refers to organs)

Question 11

What is the side of the serous membrane called that is NOT in contact with the heart?

Answer 11

the parietal layer