Embryology

Question 1

Bulbis Cordis

Answer 1

Smooth parts of the ventricles (outflow tract of the ventricles)

Question 2

Primitive Atrium

Answer 2

Trabeculated Left and Right atrium

Question 3

Primitive Ventricle

Answer 3

Trabeculated part of the Left and right ventricles

Question 4

Left horn of the sinus Venosus

Answer 4

Coronary sinus

Question 5

Primitive pulmonary vein

Answer 5

Smooth part of the left atrium

Question 6

Right horn of the sinus Venosus

Answer 6

Smooth part of the Right atrium

Question 7

Right common cardinal vein and right anterior cardinal vein

Answer 7

Superior vena cava

Question 8

Cardiac looping

Answer 8

Primary heart tube loops to establish left-right polarity

4wks

Question 9

Atrial Development

Answer 9

1. Septum primum develops - growing down to the endocardial cushions- narrows the foramen primum
2. Foramen secundum starts to form in the septum primum- closes off the foramen, septum secundum forms its own foramen to maintain the R to L shunt
3. Septum secundum closes off most of the foramen secundum leaving only a small opening : foramen ovale
   as this this happening the septum primum is degenerating
4. The remaining septum primum becomes the valve for the foramen ovale
5. At birth - with first breath, primum and secudum fuse closing off the foramen ovale

Question 10

Truncus Arteriosus

Answer 10

Ascending aorta

Pulmonary Trunk