Heart Development And Fetal Circulation

Question 1

What a re the components of the heart tube

Answer 1

Aortic sac: the ascending aorta and brachiocephalic trunk
Trunchus arteriosus: ascending aorta and pulmonary trunk
Bulbous cordius: right atrium and the outflow tracks
Primitive atrium
Primitive ventricle
Sinus venosus
(Common cardiac vein, umbilical vein, vitelline vein)

Question 2

What forms the notochord

Answer 2

Cells from the mesoderm

Question 3

What layer forms the neural tube

Answer 3

The ectoderm

Question 4

What are the areas of the mesoderm for the heart

Answer 4

paraxial
Intermediate
Lateral (somatic and splanchnic)

Question 5

What area of the mesoderm would be mostly involved in the formation of the heart tube

Answer 5

The splanchnic
Would form the heart tube and the pericardial cavity

Question 6

What anchors the heart tube

Answer 6

The dorsal mesocardium

Question 7

What does the dorsal mesocardium form when it degenerates

Answer 7

Transverse sinus of the heart (drains blood from the veins of the cerebellum and the inferior surface of the brain)

Question 8

What forms the septum intermedium

Answer 8

The neural crest cells

Question 9

What are the steps of the septum formation

Answer 9

The septum intermedium would be formed from he neural crest cells
So would the septum primum
Gap between he two would be the ostium primum
Septum primum and the septum intermedium come together
New gap is the ostium secondum (Forman ovale)
Second septum seconding would be formed in he RA

Question 10

What are the areas of the interventricular septum

Answer 10

The membranous area (most likely to have damage)
The muscular layer

Question 11

What area of the interventricular septum would be more prone to damage

Answer 11

The membraneous area

Question 12

What area would form the inflow tracts and what would form what

Answer 12

The right horn
The umbilical vein would degenerate
The Common cardinal vein forms the superior vena cava
The vitelline vein forms the inferior vena cava

Question 13

What happens to the left horn of the heart

Answer 13

Would degenerate
The sinus venosus would be taken up by the right atrium
Forms the pacemaker

Question 14

What else does the sinus venosus form

Answer 14

The visceral pericardium around the heart

Question 15

How are the outflow tracks formed

Answer 15

The bulbous cordis
Neural crest cells (truncal ridge and the bulbar ridge at the bottom)
Come together and give the aortio-pulmonary septum
Would then the rotation, would give the aorta and the pulmonary artery’s

Question 16

What are the characteristics of fetal circulation

Answer 16

Right side would have more pressure then the left side
No developed lungs
Hypoxic, so would have pulmonary to conserve oxygen

Question 17

What is the path taken by the oxygenated blood

Answer 17

From the placenta up the umbilical vein
Through the ducteous venosus in the liver
Through to the right atrium
High pressure would force into the left atrium and ventricle
Though the aorta and to the body
Some would go down the ducteous arteriosus (so to the umbilical artery)

Question 18

Whats the oath of the deoxygenated blood

Answer 18

Gravity would push done to the right ventricle
Up the pulmonary artery
Through the ducteous arteriosus
Down the umbilical artery and then to the placenta

Question 19

What does the Foreman ovale form

Answer 19

The fossa ovale

Question 20

What does the ductus venosus shunt form

Answer 20

The ligamentum venosum (liver ligament)

Question 21

What does the ducteous arteriosus shunt form

Answer 21

Ligamentum arteriosum (connects pulmonary trunk and aorta)

Question 22

What do the umbilical artery’s form

Answer 22

The medial umbilical ligament

Question 23

What does the umbilical vein forms

Answer 23

The ligamentum teres

Question 24

What do the majority of the heart defects stem form

Answer 24

Trisomy 21

Question 25

What happens in the right to to left shunt

Answer 25

Deoxygenated blood would go to to the left side of the body, would then have he blueing of the limbs (would not be getting enough oxygen)

Question 26

What Happens in the left to right shunt defect

Answer 26

Systematic system would still get the deoxygenated blood
Would soon have the blood going to the right, the pulmonary system would not be able to handle the high pressure
Would have hypertrophy of the walls
Blood would come back and would soon have a right to left shunt created

Question 27

What mainly causes the left to right shunt defect

Answer 27

Atrium and Ventricle septum defect

Question 28

What would mainly cause the right to left shunt defects

Answer 28

Transposition of the great artery’s
The aorta and the pulmonary artery’s would swap sides

Question 29

What is the tetralogy of the fallout

Answer 29

4 conditions that would be caused from the heat defects
Ventricle septum defects
Hypertrophy
Pulmonary stenosis (valve would not close properly)
Aortic displacement (aorta starts where the septum defect is)

Question 30

What forms to transverse sinus of the heart

Answer 30

Dorsal mesocardium

Question 31

What is the oblique sinus

Answer 31

Posterior to the left atrium
Would allow the expansion of the left atrium

Question 32

At what day does the hear start to beat

Answer 32

Day 22

Question 33

What cells mainly form the septum’s of the heart

Answer 33

The neural crest cells