Heart Development

Question 1

Cardiogenic Field

Answer 1

• Blood islands form in the visceral (splanchnic) layer of lateral plate mesoderm, cranial (in front) to developing brain
• Horseshoe-shaped endothelial tube (primitive heart) develops as blood islands coalesce
• Lateral body folding brings the 2 sides to the middle to fuse

Question 2

Cardiac Looping

Answer 2

Atria grows up and to the left

Ventricular grows down and right

Question 3

Ductus Venosus

Answer 3

Bypass liver, regulate BP

Takes blood from placenta to heart

Question 4

Foramen Ovale

Answer 4

Shunt btw L and R atrium

Bypassing pulmonary circuit

Question 5

Ductus Arteriosus

Answer 5

Connects pulmonary artery with aortic arch

Bypass lungs

Question 6

Cardiac Muscle Features

Answer 6

Intercalated discs

Striation

Central nuclei

Branching

Involuntary

Made from Mesoderm

Rely on T tubule system

Conducting cells

Question 7

Epicardium

Answer 7

Outer layer

Visceral pericardium

Simple squamous epithelium

Fibrocollagenous tissue

Question 8

Myocardium

Answer 8

Cardiac myocytes

Collagenous connective tissue

Question 9

Endocardium

Answer 9

Inner lining of atria and ventricles

Layer of simple squamous epithelium

Contain Purkinje fibers