5 Development of Great Vessels

Question 1

Role of vitelline vv.

Answer 1

deoxygenated blood from yolk sac –> sinus venosus

Question 2

Role of umbilical vv.

Answer 2

oxygenated blood from placenta –> sinus venosus

Question 3

Role of cardinal vv.

Answer 3

deoxygenated blood from body of embryo –> sinus venosus anterior = superior to heart posterior = inferior to heart

Question 4

right anterior cardinal vein…

Answer 4

R brachiocephalic v. superior vena cava

Question 5

left anterior cardinal vein…

Answer 5

L brachiocephalic

Question 6

posterior cardinal vein…

Answer 6

root of azygos v. common iliac vv.

Question 7

R umbilical vein…

Answer 7

degenerates

Question 8

L umbilical vein…

Answer 8

umbilical v. ductus venosus (embryo) ligamentum venosum (adult)

Question 9

Role of ductus venosus

Answer 9

Venous shunt between L umbilical vein and IVC. Takes oxygenated blood right to heart, bypassing sinusoidal capillaries of liver.

Question 10

R vitelline v.

Answer 10

IVC (hepatic portion, heart –> caudal edge of liver) Contributes to hepatic portal system.

Question 11

L vitelline v.

Answer 11

Contributes to hepatic portal system.

Question 12

R horn of sinus venous…

Answer 12

Larger. Sinus venarum of R atrium (smooth)

Question 13

L horn of sinus venous…

Answer 13

Smaller. Coronary sinus (drains into R atrium).

Question 14

Dorsal aortae

Answer 14

Unfused in region of pharyngeal arches. Fused distally –> descending aorta.

Question 15

1st pharyngeal arch aa.

Answer 15

Largely degenerate. Maxillary aa.

Question 16

2nd pharyngeal arch aa.

Answer 16

Largely degenerate. Stapedial aa.

Question 17

3rd pharyngeal arch aa.

Answer 17

Common carotid aa. Proximal internal carotid aa.

Question 18

L 4th pharyngeal arch aa.

Answer 18

Middle portion of aortic arch (L CC –> L subclav)

Question 19

R 4th pharyngeal arch aa.

Answer 19

Proximal R subclavian a. *R recurrent laryngeal n.

Question 20

5th pharyngeal arch aa.

Answer 20

Degenerates on both sides

Question 21

L 6th pharyngeal arch aa. - proximal

Answer 21

Proximal left pulmonary aa.

Question 22

L 6th pharyngeal arch aa. - distal

Answer 22

Ductus arteriosus (closes after birth as ligamentum arteriosum) * L recurrent laryngeal

Question 23

R 6th pharyngeal arch aa. - proximal

Answer 23

Proximal right pulmonary aa.

Question 24

R 6th pharyngeal arch aa. - distal

Answer 24

Degenerates

Question 25

Recurrent laryngeal nerves.

Answer 25

Associated with 6th pharyngeal arch aa. R: hooks behind R subclavian aa. L: hooks under ligamentum arteriosum.

Question 26

Aortic sac...

Answer 26

Proximal portion of aortic arch Brachiocephalic trunk

Question 27

Truncus arteriosus...

Answer 27

Ascending aorta Pulmonary trunk

Question 28

R unfused portions of dorsal aortae

Answer 28

mostly regress

Question 29

L unfused portions of dorsal aortae

Answer 29

forms rest of aortic arch, distal to L subclavian a.

Question 30

3 contributors to aortic arch

Answer 30

proximal: aortic sac middle: L 4th arch distal: L unfused dorsal aortae

Question 31

vitelline arterial plexus...

Answer 31

celiac trunk, SMA, IMA

Question 32

umbilical aa carry...

Answer 32

deoxygenated blood from embryo --\> placenta

Question 33

umbilical vv carry...

Answer 33

oxygenated blood from placenta --\> sinus venosus of embryonic heart

Question 34

umbilical aa...

Answer 34

proximal aa: internal iliac aa, superior vesical aa, distal aa: medial umbilical ligament

Question 35

Source of O2 before/after birth

Answer 35

Before birth: O2 from placenta After birth: O2 from lungs

Question 36

At birth, placental circulation closes off. Ductus venosus... Umbilical vv... Distal umbilical aa...

Answer 36

DV --\> ligamentum venosum UV --\> ligamentum teres hepatis DUA --\> medial umbilical ligaments

Question 37

At birth, increased pulmonary circulation... 1st BP

Answer 37

Inc. BP in L atrium (receiving oxygenated blood from lungs)

Question 38

At birth, increased pulmonary circulation... 2nd foramen ovale...

Answer 38

foramen ovale closes off as fossa ovalis (no flow b/w atria)

Question 39

At birth, increased pulmonary circulation... 3rd ductus arteriosus...

Answer 39

ligamentum arteriosum (no blood flow from pulmonary trunk to aortic arch)

Question 40

Which vessels are responsible for carrying deoxygenated blood from the body of the embryo into the sinus venosus?

Answer 40

cardinal vv.

Question 41

ID upper and lower arrow.

Answer 41

upper: ductus venosus lower: left umbilical vein

Question 42

ID structure

Answer 42

medial umbilical ligaments. These structures are the closed off remnants of the distal portions of the paired umbilical aa.