In Cardiac Development Heart starts to form in
[A] Second week of gestation
[B] Third week of gestation
[C] Fourth week of gestation
[D] Fifth week of gestation
Cardiac Development
Cardiac Development
- Heart starts to form in the third week of gestation
- Heart fully formed by 8 weeks gestation.
- Primary heart fields – Mesodermal precardiac cells migrate to form the cardiac crescents (primary heart fields) in anterior lateral plate mesoderm, which are then brought together to form a primary linear heart tube by ventral closure of the embryo.
- Second heart field – Cells of the second heart field continue to proliferate outside the heart and are added to the heart tube over the course of embryogenesis, contributing to the
- Atria
- Right ventricle
- Outflow tract
- Cardiac neural crest cells – migrate into the developing heart in the 5th to 6th weeks and are essential for
- Septation of the outflow
- Formation of the semilunar valves
- Patterning of the aortic arches
- D- loop –
- Heart tube grows and elongates by addition of cells from the second heart field.
- The ends of the heart tube are relatively fixed by the pericardial sac so that as it elongates it must loop (bend
- Majority of hearts the loop falls to the right (D- loop)
