Development Of The Heart Muscle Flashcards
How is the heart divided into left and right?
Neural crest cells migrate from the neural tube to the atrioventricular canal. They occupy the primitive myocardium and develop into endocardial cushions. The cushions narrow the canal until they fuse at the midline.
What is septation?
The process by which the heart tube is divided into two pumps
Name the septa to develop in atrial septation
Septum primum
Septum secundum
What is the name hole formed just before the septum primum fuses with the endocardial cushions?
The ostium primum
What is the name of the hole that appears in the septum primum?
Ostium secundum
What is the name of the hole in the septum secundum?
Foramen ovale
Why does the adult right atrium have a rough wall?
Where the right atrium absorbed the sinus venosus
What are the two components of ventricular septation?
Muscular and membranous
Describe how the muscular component grows
Grows upwards towards the fused endocardial cushions. It leaves a small gap
What is the name of the small gap that the muscular component leaves?
Primary interventricular foramen
What is the membranous component made up of?
Connective tissue
What is septation of the outflow tract made by?
The conotruncal septum
How does the foetus receive oxygenated blood?
The placenta and umbilical vein
How does the foramen ovale close at birth?
Due to respiration, the pressure in the left atrium increases above the pressure of the right atrium. This pushes the septum primum against the septum secundum.
After birth, what does the foramen ovale become?
The fossa ovalis
AB, what does the ductus arteriosus become?
The ligamentum arteriosum
AB, what does the ductus venosus become?
Ligamentum venosum
AB, what does the umbilical vein become?
The ligamentum teres
What is the ductus arteriosus?
Blood vessel connecting the pulmonary artery to the descending aorta
What is the ductus venosus?
Shunts blood from the umbilical vein directly to the inferior vena cava. Allows blood to bypass the liver
