Embryo heart

Question 1

Cardiovascular system derived from which germ layer?

Answer 1

mesoderm

Question 2

CV system forms in which embryonic body cavity?

Answer 2

intraembryonic coelom

Question 3

Pharyngeal endoderm induces mesoderm to form..

Answer 3

blood islands and cardiac myocytes in the intraembryonic coelom

Question 4

Where does the cardiogenic area start off at?

Answer 4

anterior to the oropharyngeal membrane- moves to thorax with cranial folding

Question 5

Angiogenic cords from cardiogenic mesoderm are precursors to what?

Answer 5

paired heart tubes –> aorta and heart

Question 6

Vitelline, umbilical, and cardinal arteries and veins empty at…

Answer 6

caudal end of fetus

Question 7

The heart tube is precursor to…

Answer 7

aortic sac, truncus arteriosus, bulbis cordis, primitive ventricle, primitive atrium, sinus venosus

Question 8

Endocardial cushions important for…

Answer 8

Partitioning primitive atrium and ventricle,

Partitioning of R and L AV canals, role in formation of AV valves

Question 9

Circulation in primitive heart:

Answer 9

umbilical v (high O2), cardinal v (low O2), vitelline v (low O2) –> sinus venosus –> atria –> ventricle –> bulbus cordis –> truncus arteriosus –> aortic arches –> dorsal aorta –> body and placenta

Question 10

primitive atria are divided by 2 septa

Answer 10

1. septum primum

2. septum secundum

Question 11

interventricular septum

Answer 11

thick mesodermal tissue that grows towards endocardial cushions

caused by differential (fast) growth of cells in the IV septum region

Question 12

2 parts of interventricular septum

Answer 12

membranous- forms at bulbar ridges

muscular

Question 13

foramen primum

Answer 13

formed near the endocardial cushions as the septum primum grows towards the endocardial cushions

Question 14

foramen secundum

Answer 14

formed by fenestrations of septum primum

Question 15

foramen ovale formed in which septum?

Answer 15

formed in the septum secundum

covered by flap of septum primum

Question 16

role of foramen ovale

Answer 16

shunts blood from R –> L atrium

allows blood to bypass lungs

Question 17

when does foramen ovale close and how does it exist in the adult?

Answer 17

closes at birth when L atrium pressure increases and pulmonary vascular resistance decreases

remains as fossa ovalis

Question 18

patent foramen ovale

Answer 18

occurs when flap of septum primum does not close

Question 19

separation of the aorta and pulmonary artery occurs by…

Answer 19

180 degree spiraling of conotruncal ridges in truncus arteriosis –> aorticopulmonary septum

Question 20

pulmonary artery is ___ (position) to the aorta

Answer 20

anterior

Question 21

semilunar valves

Answer 21

aortic and pulmonary valves

Question 22

what forms the semilunar valves

Answer 22

the connection between the conotruncal ridges and the interventricular septum

Question 23

what forms the AV valves?

Answer 23

from proliferation of tissue around the endocardial cushions

Question 24

aortic arches

Answer 24

connected to the dorsal aorta, associated with the corresponding pharyngeal arch

Question 25

left 4th pharyngeal aortic arch derivative

Answer 25

forms most of aortic arch itself

Question 26

left 6th pharyngeal aortic arch

Answer 26

forms ductus arteriosis that shunts blood from pulmonary artery --> aorta

Question 27

fetal circulation is defined by 3 shunts

Answer 27

1. ductus arteriosis 2. foramen ovale 3. ductus venosus

Question 28

ductus venosus

Answer 28

shunts oxygenated blood from umbilical vein to IVC bypasses liver

Question 29

remnants of the 3 shunt systems:

Answer 29

1. ductus arteriosis to ligamentum arteriosis 2. foramen ovale to fossa ovalis 3. ductus venosus to ligamentum venosus umbilical vein to ligamentum teres (round ligament) of falciform

Question 30

tetralogy of fallot

Answer 30

1. overriding aorta 2. pulmonary stenosis 3. right ventricle hypertrophy 4. ventricular septal defect

Question 31

umbilical vein - high or low O2?

Answer 31

high O2

Question 32

cardinal veins- high or low O2

Answer 32

low O2

Question 33

vitelline veins- high or low O2

Answer 33

low O2

Question 34

umbilical vein drains from?

Answer 34

placenta

Question 35

cardinal veins drain from?

Answer 35

embryo body

Question 36

vitelline veins drain from?

Answer 36

yolk sac and GI tract

Question 37

derivatives of cardinal veins

Answer 37

right- SVC | left- major veins like coronary sinus, int. jugular, brachiocephalic, azygous, common iliac

Question 38

derivatives of vitelline veins

Answer 38

right- hepatic v, IVC | left- (hepatic) portal v.

Question 39

derivatives of umbilical vein

Answer 39

ligamentum venosus | ligamentum teres of falciform ligament

Question 40

derivative of sinus venosus

Answer 40

smooth RA

Question 41

derivative of primitive atrium

Answer 41

RA, LA

Question 42

derivative of primitive ventricle

Answer 42

LV, RV- trabeculated

Question 43

deriv of bulbus cordis

Answer 43

LV, RV- smooth

Question 44

deriv of truncus arteriosis

Answer 44

aorta and pulmonary trunk

Question 45

deriv of aortic sac and dorsal aorta

Answer 45

aortic arch and descending aorta