07 Development Of Heart

Question 1

Heart develops from

Answer 1

Cardiogenic area → Splanchnopleuric lateral mesoderm

Cranial to oropharyngeal membrane

Question 2

In the middle of 3rd week, Angioblastic cord cell froms →

Answer 2

Two endothelial heart tubes

Question 3

Two endothelial heart tubes fuse to form

Answer 3

Heart Tube - which undergoes series of dilatation and forms various parts of Heart

Question 4

Dilatation in Heart tube from Cranial to Caudal;

Answer 4

• Truncus arteriosus
• Bulbus cordis
• Primitive ventricle
• Primitive atrium
• Body of sinus venosus
• Right and Left Horns of sinus venosus

Question 5

Truncus arteriosus forms

Answer 5

Outflow tract - Aorta and Pulmonary Trunk

Question 6

Smooth wall of Right and Left Ventricle is formed by;

Answer 6

Bulbus cordis

Question 7

Primitive ventricle will form

Answer 7

Rough part of Right and Left Ventricle

Question 8

Primitive atrium will form

Answer 8

Rough part of Right and Left Atrium

Question 9

Body and Right horn of sinus venosus forms

Answer 9

Smooth wall of Right Atrium

Question 10

Left horn of sinus venosus will form the

Answer 10

Coronary sinus

Question 11

Smooth wall of left atrium is formed due to

Answer 11

Absorption of Pulmonary Veins

Question 12

The septum which divides Truncus arteriosus

Answer 12

Conotruncal septum / Spiral septum / Aorticopulmonary septum

Divides Truncus arteriosus into Aorta and Pulmonary trunk

Question 13

Conotruncal septum / Spiral septum / Aorticopulmonary septum derived from;

Answer 13

Neural crest cells

Question 14

Normal Orientation of Conatruncal seprtum

Answer 14

Is Spiral due to which blood from

Right ventricle → Pulmonary trunk

Left Ventricle → Aorta

Question 16

What is Overriding Aorta?

Answer 16

Aortic orifice receives blood from Right and Left Ventricle

Question 17

Straight / Non-spiral course of Conotruncal septum leads to

Answer 17

Transposition of Great vessels

Right ventricle → Drains into Aorta

Left ventricle → Drains into Pulmonary trunk

Question 18

When Truncus arteriosus will persist

Answer 18

If Neural crest cells fail to migrate

→ the truncus arteriosus will persist

→ Persistent Truncus arteriosus

Question 19

Anterior displacement of Conotruncal septum leads to

Answer 19

1. Pulmonary Stenosis
2. Over-Riding of Aorta
3. RV Hypertrophy
4. VSD

Tetralogy of Fallot

Question 20

During entire Intrauterine life - How Left Atrium receives blood

Answer 20

By Shunt - From Right atrium to Left atrium

Because lungs are not functioning in Intrauterine life

Question 21

Opening between the AV cushion and Septum primum

Answer 21

Ostium primum

Question 22

Gradual Downward growth of septum primum (towards AV cushion) leads to

Answer 22

Narrowing of ostium primum (and eventually closure)

Question 23

Gap between septum primum and septum secundum is called as

Answer 23

Foramen ovale

Question 24

After birth Increased Pressure in the left atrium leads to

Answer 24

Septum primum fuse with Septum

Question 25

In 20% of people, the gap between Septum secundum and Septum primum persists, is called

Answer 25

Probe patency of Foramen Ovale

Anatomically Present
Physiology closed

Question 26

Remnant of Septum primum will form

Answer 26

Fossa ovalis

Question 27

Remnant of Septum secundum will form

Answer 27

Limbus fossa ovalis

Question 28

Three parts of Interventricular septum

Answer 28

1. Muscular part
2. Membranous part
3. Infundibular part / Outflow part

Question 29

Muscular part of Interventricular septum derived from

Answer 29

Myocardium

Question 30

Membranous part of Interventricular septum derived from

Answer 30

Endocardial cushion

Question 31

Outflow part / Infundibular part derived from the

Answer 31

Conus septum (bulbar septum) ← derided from Neural crest cells