Fetal Circulation

Question 1

Before birth
Blood from the placenta, (——– saturated with oxygen),
reaches the fetus by the ———- vein.

Answer 1

80% - umbilical vein

Question 2

most of this blood flows through the

————- directly into—————- the, bypassing the ——————-

Answer 2

DUCTUS VENOSUS- inferior vena

cava-liver

Question 3

Placental blood mixes with—————- blood

returning from the in the IVC

Answer 3

deoxygenated-lower limbs

Question 4

Then IVC enters the———

Answer 4

right atrium.

Question 5

Most of the blood from the IVC enters
the left atrium through ———-It then flows into the ——then——
into the aorta

Answer 5

foramen ovale-left ventricle-into the aorta

Question 6

A small amount from the ———- is prevented
from entering the left atrium and remains in
the——atrium. It mixes with desaturated blood returning
from the head and arms by the ————–

Answer 6

IVC- right - superior vena

cava.

Question 7

Desaturated blood from the superior vena
cava enters the ——— ventricle and then into
the ——–

Answer 7

right-pulmonary trunk.

Question 8

blood move from descending aorta then —————— which carry —————– and then —————-and the placenta

Answer 8

umbilical arteries - deoxygenated- umbilical cord

Question 9

the first arteries rise from aorta are _________and______

Answer 9

coronary artery to supply wall of heart

carotid artery to supply the brain

Question 10

Resistance in the pulmonary vessels is ————most of this blood passes through the DUCTUS
ARTERIOSUS into the ————It mixes with blood from the —————–It passes through the descending aorta——————-It returns to the placenta by —————–

Answer 10

high- descending aorta-proximal aorta-two umbilical arteries.

Question 11

The oxygen saturation in the umbilical arteries is

approximately ——————-

Answer 11

58%.

Question 12

small amount of blood in pulmonary trunk from right ventricle will go to ———–to supply tissue

Answer 12

lung

Question 13

Circulatory changes at birth : 2things

Answer 13

• Cessation of placental blood flow

- The beginning of respiration.

Question 14

baby cry after birth because of

Answer 14

start lung working ( beginning of respiration)

Question 15

Closure of umbilical arteries: by

Answer 15

contraction of smooth musculature in their walls

Question 16

distal parts of umbilical arteries form ——–

Answer 16

medial umbilical ligaments

Question 17

proximal parts of umbilical arteries remain open as————–

Answer 17

superior vesical arteries

Question 18

Closure of umbilical vein to forms the ——————

Answer 18

ligamentum teres of liver

Question 19

. Obliteration of ductus venosus to form ———-

Answer 19

ligamentum venosum

Question 20

Closure of ductus arteriosus to form the————
how ? Muscular wall of the duct———— immediately after birth
• The amount of blood flowing through the lung —————rapidly.

Answer 20

ligamentum arteriosum-contracts-increases

Question 21

Closure of oval foramen
• Pressure in the right atrium ——— as a result of————-placental blood flow.
• Pressure raises in the ——– atrium.
• The septum———— is then apposed to the septum ———-and functionally the foramen
oval closes.

Answer 21

decreases-interruption-left- primum-secundum

Question 22

closure of the umbilical vein postnatally result in the formation of

Answer 22

ligamantum teres

Question 23

ductus arterosis prenatally connect

Answer 23

pulmonary trunk with arch of aorta