Unit 4 - Wk 1 Embryology

Front 1

From which layer does the cardiovascular system develop?

Back 1

Mesoderm; yolk sac plus splanchopleuric mesoderm

Front 2

Back 2

Early step in heart development is the fusion of a pair of tubes; the tubes are initially on the right and left sides of early embyro, folding brings them together in the midline

Front 3

Splanchopleuric mesoderm

Back 3

Mesoderm that touches an organ (medial red lines)

Back 4

Pericardial Cavity formation; bronchial buds expand, common cardinal veins merge in the midline to form inferior vena cava

Note that the phrenic nerve runs laterally on the pericardium

Front 5

Back 5

Pericardial Cavity formation; bronchial buds expand, common cardinal veins merge in the midline to form inferior vena cava

Note that the phrenic nerve runs laterally on the pericardium

Front 6

Back 6

Dextral looping; in the primitive heart tube blood flows through the left ventricle prior to the right ventricle; dextral looping corrects this and properly aligns the chambers

Front 7

Where do the atrioventircular valves develop?

Back 7

On endocardial cushions w/ attachments to chordae tendinae and papillary muscles

Front 8

What cells make up the truncoconal septum

Back 8

Forms from neural crest cells that migrate into the wals of the outflow tract; it must spiral/fuse to ensure that the pulmonary trunk connects to the right ventricle and the aorta connects to the left ventricle

Front 9

Persistent Truncus

Back 9

Truncoconal septum does not form

Front 10

Ventricular Septal Defect

Back 10

Membranous interventricular septum (from the truncoconal septum) fails to fuse to the muscular interventricular septum

Front 11

Transposition of Vessels

Back 11

Occurs if truncoconal septum fails to spiral

Front 12

Back 12

Tetralogy of Fallot; septum forms off center towards the right