Development Of The CVS Flashcards
What type of folding creates the heart tube?
Lateral folding
What does the CVS develop from?
The mesoderm
What type of folding brings the heart tube into the thoracic region?
Cephalocaudal folding
In which direction does the blood flow in the primitive heart tube?
From caudal to cranial
Name the four regions of the heart tube
Atrium
Ventricle
Bulbous cordis
Truncus arteriosus
When does looping begin and end?
Day 23
Day 28
What does looping result in?
A transverse pericardial sinus with the arteries in front of the veins
Places the inflow and outflow cranially with the inflow dorsal (behind) the outflow
After looping, how does the atrium communicate with the ventricle?
The atrioventricular canal
How is the heart tube formed?
A pair of endocardial tubes develop within the cardiogenic field. They are brought together during lateral folding, fusing in the midline.
During looping, in which direction does the cephalic end move?
Ventrally, caudally and to the right
In looping, in which direction does the caudal end move?
Cranially, dorsally and to the left
In which positions does looping put the primordia of the ventricles in?
Left ventricle closest to outflow tract.
Right ventricle closest to inflow tract
What separates the thoracic cavity from the abdominal cavity?
The diaphragm
What does the right atrium develop from?
Most of the primitive atrium and the sinus venosus
What does the left atrium develop from?
The small part of the primitive atrium and absorbs proximal parts of the pulmonary veins
What does the right ventricle develop from?
The bulbus cordis
What does the left ventricle develop from?
Primitive ventricle
What does the truncus arteriosus give rise to?
Roots and proximal portions of the pulmonary trunk and the aorta.
What does the arterial system begin as?
A bilaterally symmetrical system of arched vessels
What are the aortic arches numbered?
1, 2, 3, 4, 6
What does the 4th arch become?
Right arch: the proximal part of right subclavian artery
Left arch: the arch of the aorta
What does the 6th arch become?
Right arch: right pulmonary artery
Left arch: left pulmonary artery and ductus arteriosus
What is the nerve corresponding to the 6th arch?
The recurrent laryngeal nerve
What factors influence the course of the nerve?
Caudal shift of the developing heart and expansion of the developing neck region
Need for a foetal shunt between the pulmonary trunk and the aorta
In which week does the embryo fold in?
4
