Heart Development - WTF

Question 1

Before birth, how is blood shunted?

Answer 1

From right to left atrium

Question 2

When does heart formation begin and when does heart start beating?

Answer 2

3 weeks

4 weeks

Question 3

Initial function of heart

Answer 3

One way pump to transport O2 blood from placenta to the embryo

Question 4

Umbilical vein function

Answer 4

Carries blood from placenta to embryo

Question 5

Umbilical arteries functionm

Answer 5

Carry blood from embryo to placenta

Question 6

Cardiogenic region…where is it and what happens?

Answer 6

At the rostral end…mesodermal cells aggregate to form longitudinal cellular strands (angioblastic cords)

Question 7

What germ layer is the majority of the heart composed from?

Answer 7

Splanchnic mesoderm

Question 8

How is primitive heart tube formed?

Answer 8

Angioblastic cords hollow out to form endocardial heart tubes

Question 9

What does longitudinal folding accomplish for the heart?

Answer 9

Positions it in the thorax

Question 10

Embryonic folding brings

Answer 10

Two endocardial tubes into the thorax where they meet along midline and fuse to form a single tube

Question 11

Fused endocardial tubes form the ______

Answer 11

Inner lining of the heart

Endocardium

Question 12

What happens to mesoderm below pericardial coelom as heart tube fuses?

Answer 12

Forms cardiac jelly and myocardium

Question 13

Pericardial coelom is the future _______

Answer 13

pericardial cavity

Question 14

Cardiac jelly

Answer 14

Thick, inner gelatinous mix

Question 15

Myocardium

Answer 15

Muscular layer

Question 16

Parietal pericardium is from ______ mesoderm

Answer 16

Somatic

Question 17

Visceral pericardium from ______ mesoderm

Answer 17

Somatic

Question 18

Dorsal mesocardium does what and then leaves what remnant?

Answer 18

Anchors heart at the beginning and goes away to form transverse pericardial sinus

Question 19

Flow through the parts of pirmitive heart tube

Answer 19

Sinus venosus——atrium—–ventricle——bulbis cordis——–truncus arteriosis———aortic arch vessels

These are caudal to rostral

Question 20

Pericardial sac from what parts of the primitive heart tube?

Answer 20

Ventricle
Bulbis cordis
Truncus arteriosis

Question 21

Truncus arteriosis becomes

Answer 21

Pulmonary trunk

Question 22

How does sinus venosus receive blood

Answer 22

Common cardinal veins (body)
Umbilical veins (placenta)
Vitelline veins (yolk sac)

Question 23

Blood flows from the aortic arches into the _________ to reach the body, placenta, and yolk sac

Answer 23

DOrsal aortae

Question 24

Dextrocardia`

Answer 24

Heart abnormally positioned on the right side of the thorax

Question 25

Dextrocardia with situs inversus

Answer 25

No cardiac abnormality because inversion of all organs

Question 26

Four sets of partitions of primitive heart

Answer 26

Atria and ventricles R and L atria R and L ventricle Pulmonary trunk and ascending aorta

Question 27

Atrioventricular canal and what develops there during week 4

Answer 27

Between pirmitive atrium and ventricle | Endocardial cushions

Question 28

Endocardial cushions grow together to create

Answer 28

Atrioventricular septum

Question 29

Septum primum grows how?

Answer 29

From roof of atrium and extends toward endocardial cushions

Question 30

Ostium primum

Answer 30

Opening between sptum primum and the endocardial cushions

Question 31

How does septum secundum grow?

Answer 31

From roof immediately to the right of the septum primum

Question 32

Part septum secundum and the septum primum grows to touch the

Answer 32

Endocardial cushions that formed the membranous portion of IV septum

Question 33

Blood circulation before birth

Answer 33

Foramen ovale shunts blood entering the right atriumn into the left atrium and prevents passage moving oppostie way

Question 34

After birth, what happens to foramen ovale?

Answer 34

Septum primum and secundum pressed together to form fossa ovalis

Question 35

What causes foramen ovale closure?

Answer 35

Decreased RA pressure and increased LA pressure

Question 36

Atrial septal defects

Answer 36

INcomplete anatomical fusion of septum primum and secundum

Question 37

How does right atrium remodel its wall?

Answer 37

Right side of sinus venosus incorporated into the side of the atrium

Question 38

Sinus venarum

Answer 38

Part of atrium that contains incorporated sinus venosus

Question 39

Original right side of primitive atrium becomes

Answer 39

Right auricle

Question 40

Left atrium wall remodeling

Answer 40

Incorporation of pulmonary vein

Question 41

Pulmonary vein divids to produce ____

Answer 41

4 pulmonary veins

Question 42

4 pulmonary veins anastomose with

Answer 42

Veins developing in mesoderm around bronchial buds

Question 43

Left side of primitive atrium becomes the

Answer 43

Left auricle

Question 44

What must be partitioned to create pulmonary trunk and ascending aorta and what are their parts called

Answer 44

Bulbis cordis and truncus arteriosis | Truncal and bulbar ridges

Question 45

Formation of aorticopulmonary trunk creates

Answer 45

two outflow paths

Question 46

Truncal and bulbar ridges made from

Answer 46

neural crest cells

Question 47

Shape of wall of aorticopulmonary segment

Answer 47

Spiraling

Question 48

Two sections of IV septum

Answer 48

Membranous - from endocardial cushions | Muscular -

Question 49

Persistant truncus arteriosis

Answer 49

Abnormal neural crest cell migration so only partial AP septum ONly a large vessel leaves the heart and receives blood from both Cyanosis

Question 50

Transpotion of great arteries

Answer 50

Aorticopulmonary septum is straight line rather than spiral Aorta is from RV and pulmonary trunk from LV Fatal unless patent ductus arteriosis Most common cause

Question 51

Tetraology of Fallot

Answer 51

Abnormla neural crest cell migration Truncus arteriosis not divided equally Pulmonary stenosis and overriding aorta Results in VSD

Question 52

Pulmonary stenosis and overriding aorta

Answer 52

Small pulmonary trunk diameter | Aorta large diameter

Question 53

4 signs of tetraology of fallot (actually 5)

Answer 53

``` Pulmonary stenosis Right ventricle hypertrophy Overriding aorta VSD Cyanosis ```

Question 54

Most VSDs shunt blood from

Answer 54

Left to right

Question 55

Result of VSD

Answer 55

pulmonary hypertension

Question 56

types of VSD

Answer 56

Membranous (most common) Muscular Common ventricle

Question 57

Persistent atrioventricular canal is a result of

Answer 57

Endocardial cushions failing to fuse to atrial and ventricular septa

Question 58

Primitive atria becomces

Answer 58

Auricles of right and left atria

Question 59

Right horn of sinus venosus becomes

Answer 59

Smooth part of right atrium (sinus venarum)

Question 60

Left horn of sinus venosus becomes

Answer 60

Coronary sinus

Question 61

Primitive pulmonary veins becomes

Answer 61

Smooth part of left atrium

Question 62

Conus cordis becomes

Answer 62

``` Outflow for both ventricles Conus arteriosis (RV) Aortic vestibule (LV) ```

Question 63

Bulbis cordis becomes

Answer 63

Trabeculated RV

Question 64

Primitive ventricle becomes

Answer 64

Trabeluated LV

Question 65

Truncus arteriosis becomes

Answer 65

Ascending aorta and pulmonary track

Question 66

Ductus arteriosis shunts blood from

Answer 66

Pulmonary artery to the aorta

Question 67

Foramen ovale shunts blood from the

Answer 67

Right atrium to the left atrium