Embryology - Part 1

Question 1

which (specific) plate of the mesoderm does the circulatory system arise from?

Answer 1

lateral plate splanchnic mesoderm

Question 2

in which week of gestation does the primordial heart begin to function?

Answer 2

4th week - rapidly growing embryo so nutrition by diffusion is not enough

Question 3

when do angioblastic cords start to appear?

Answer 3

3rd week

Question 4

where do blood vessels first appear?

Answer 4

wall of the yolk sac
allantois
connecting stalk
chorion

Question 5

what do angioblastic cords become?

Answer 5

heart tubes

Question 6

what is the pericardium derived from?

Answer 6

the intra-embryonic coelom (space between the somatic and splanchnic mesoderms)

Question 7

what is the parietal layer of the serous pericardium derived from?

Answer 7

somatic mesoderm

Question 8

what is the fibrous pericardium derived from?

Answer 8

somatic mesoderm

Question 9

what is the visceral layer of the serous pericardium derived from?

Answer 9

splanchnic mesoderm

Question 10

which veins does the yolk sac drain into?

Answer 10

vitelline veins

Question 11

which veins does the placenta drain into?

Answer 11

umbilical veins

Question 12

which veins does the body of the embryo drain into?

Answer 12

common cardinal veins

Question 13

what do the aortic arches arise from?

Answer 13

aortic sac

Question 14

where do the aortic arches terminate?

Answer 14

dorsal aorta

Question 15

the formation of which primordial heart structure leads to the creation of both a left and right atrioventricular canal?

Answer 15

endocardial cushions

Question 16

does the septum secundum form on the left or right of the septum primum?

Answer 16

right

Question 17

how is the foramen secundum formed?

Answer 17

cell death

Question 18

in which membrane is the foramen secundum formed?

Answer 18

septum primum

Question 19

which foramen does the septum secundum overlap?

Answer 19

foramen secundum

Question 20

is atrial septal defect (asd) more common in males or females?

Answer 20

females

Question 21

what are the four clinically significant types of atrial septal defect (asd)?

Answer 21

foramen secundum defect
endocardial cushion defect with foramen primum defect
sinus venosus defect
common atrium

Question 22

is ventricular septal defect (vsd) more common in males or females?

Answer 22

males

Question 23

are muscular or membranous vsds more common?

Answer 23

membranous

Question 24

is congenital heart disease more common in males or females?

Answer 24

males (vsd more common)

Question 25

what is a common cause of cyanotic disease in newborns?

Answer 25

transposition of great vessels

Question 26

which 4 cardiac defects make up tetralogy of fallot?

Answer 26

pulmonary stenosis
ventricular septal defect
dextroposition of aorta
right ventricular hypertrophy

Question 27

which adult structures arise from the truncus arteriosus?

Answer 27

aorta & pulmonary trunk

Question 28

which adult structures arise from the bulbus cordis?

Answer 28

right ventricle & parts of the outflow tracts

Question 29

which ventricle is formed from the primitive ventricle?

Answer 29

left

Question 30

which adult structures arise from the sinus venosus?

Answer 30

superior vena cava & right atrium