Embryology 2

Question 1

Name the different component parts of the heart tube in order from arterial end to venous end

Answer 1

(labelled a-e).

a. truncus arteriosus
b. bulbus cordis
c. primitive ventricle
d. primitive atrium
e. sinus venosus

Question 2

What do the vitelline veins do?

Answer 2

Drain venous blood from the yolk sac to sinus venosus

Question 3

What do the umbilical veins do?

Answer 3

Drain venous blood from the placenta to sinus venoss

Question 4

What do the cardinal veins do?

Answer 4

Drain venous blood from the body of embryo to sinus of venosus

Question 5

What part of the heart tube is responsible for the formation of the cardiac loop?

Answer 5

Bulbus cordis and primitive ventricle.

Question 6

What is dextrocardia?

Answer 6

Apex of the heart is on the right side of the body. (rare congenital condition)

Question 7

Define ectopia cordis?

Answer 7

Heart is located partially or totally outside of the thorax.

Question 8

Define foramen ovale.

Answer 8

one of two cardiac shunts which allows blood to bypass the lungs because blood goes immediately from right atrium to left atrium

Question 9

What is ductus arteriosus?

Answer 9

Allows blood that still has escaped to the right ventricle to bypass the pulmonary circulation

Question 10

c. Which maternal infection (acquired during pregnancy) can often be associated with congenital heart defects?

Answer 10

Rubella

Question 11

What develops the membranous portion of the interventriclar septum and closes the IV foramen?

Answer 11

Fusion of:

a) two trunco-conal (bulbar) ridges
b) endocardial cushion
c) aorticopulmonary septum

Question 12

2 most common types of ASD?

Answer 12

• Patent foramen ovale

- Ostium secundum (foramen in septum primum)

Question 13

Reasons for foramen ovale not closing at birth?

Answer 13

• eNlarged foramen ovale
• ## inadequate growth of foramen secundum

Question 14

2 septa that form during the partition of the primordial atrium?

Answer 14

• septum primum and septum secundum

Question 15

When does the interventircular foramen close?

Answer 15

Week 7

Question 16

What is the function of the ductus arteriosus?

Answer 16

• It connects the pulmonary artery to the aorta.

- It shunts blood from the left pulmonary artery to the aorta, therefore bypassing fetal pulmonary circulation

Question 17

What Is coarctation of the aorta? Why does it occur?

Answer 17

• Narrowing of the aorta, usually where the ductus arteriosus is.
• congenital, not fully understood, construction of ductus arteriosus when it closes off to become ligaments arteriosus

Question 18

When does double aortic arch occur?

Answer 18

• in other congenital heart defects such as Tetralogy of fallot, transposition of great arteries, ventricular septal defect

Question 19

What is tetralogy of fallot?

Answer 19

4 heart problems

1. Ventricular septal defect
2. Overiridng aorta
3. Pulmonary stenosis
4. Right ventricular hypertrophy