embryology heart development

Question 1

The germ layer named _______________ gives rise to the heart, arteries and veins .

Answer 1

mesoderm

Question 2

The normal shunting of blood in the pre-natal heart moves blood from __________ atrium to ___________ atrium through holes named ______________________ .

Answer 2

right; left; ovale foramen and foramen secundum

Question 3

The structure in the embryonic heart to which the interatrial and interventricular septa both attach is the _____________________________ .

Answer 3

endocardial cushion

Question 4

The heart tube starts to beat during Week ____ of development.

Answer 4

4

Question 5

The truncus arteriosus gives rise to two major arteries named ______________________ and _______________________ .

Answer 5

pulmonary trunk/arteries and aorta

Question 6

Put this list of structures in the order in which blood flows through them:
Bulbus cordis, Atrium, Truncus arteriosus, Sinus venosus, Ventricle

Answer 6

Sinus venosus, Atrium, Ventricle, Bulbus cordis, Truncus arteriosus

Question 7

Umbilical vein becomes the ______

Answer 7

Ligamentum teres

Question 8

Foramen ovale becomes the ______

Answer 8

fossa ovalis

Question 9

Umbilical arteries becomes the ______

Answer 9

Median umbilical ligament

Question 10

Ductus arteriosum becomes the ______

Answer 10

Ligamentum arteriosum

Question 11

Ductus venosus becomes the ______

Answer 11

Ligamentum venosum

Question 12

Ductus arteriosus between _______ and _______ to bypass _________.

Answer 12

pulmonary artery; aorta; pulmonary circulation
Blood flows pulmonary artery → aorta (right–to left shunt
● Most Pulm. artery blood
passes → ductus (high
resistance in pulm arteries)
● Blood from ductus →
lower body.

Question 13

explain the path of blood that enters through the superior vena cava

Answer 13

right atrium, right ventricle, pulmonary trunk, ductus arterious, lower body

Question 14

explain the path of blood that enters through the inferior vena cava

Answer 14

right atrium, foramen ovale, left atrium, left ventricle, aorta, upper body regions

Question 15

two main differences between prenatal and postnatal circulations

Answer 15

Prenatal: The fetus is attached to the vascular structure, the placenta, where gases, nutrients and wastes are exchanged with the maternal blood.
Prenatal: The fetus does not use its lungs for breathing, so they don’t need much blood.

Question 16

The atrioventricular valves arise from the _______

Answer 16

endocardial cushion

Question 17

The _____________ grows from floor to endocardial cushion, closing the Interventricular foramen.

Answer 17

Interventricular septum

Question 18

Describe atrial subdivision

Answer 18

1. Septum primum grows from roof to endocardial cushion. (1,2,3)
2. Always need a hole. 1st is named Foramen primum.
   It disappears. (2,3,4)
3. Holes form in the septum. (3)
4. Coalesce to form 1 hole. Named Foramen secundum. (4)
5. A second septum grows on the right side of the first,
   from roof to endocardial cushion. Named Septum secundum. (5,6)
6. This septum has a hole, named Foramen ovale. This septum covers the Foramen secundum. (6)

Question 19

The Septum primum is pushed to the left and acts

as an open valve of the _______.

Answer 19

Foramen ovale

Question 20

during fetal development which atria has the greatest pressure

Answer 20

right causing blood to flow right to left

Question 21

Final positions: ventricles located ______ and atria located more ______.

Answer 21

anteriorly; posteriorly

Question 22

________ create blood cells. Later, blood cells arise in liver, spleen and bone marrow.

Answer 22

Vessel walls

Question 23

heart development takes ____ weeks

Answer 23

5.5

Question 24

Heart starts developing as a right and a left

Answer 24

blood vessel (called cords)