Formation of the Heart Loop

Question 1

At 23 days the _______ part lies within the _______ and is essentially straight.

Answer 1

Bulboventricular part

Pericardial cavity

Question 2

The cranial third of the tube is dilated and forms the ______, which will lead to the formation of the _______.

Answer 2

Aortic sac

Aortic arch

Question 3

The caudal end of the heart tube contains the area for the ______, and the mid portion will lead to the ______.

Answer 3

Ventricle

Bulbus cordis

Question 4

The Bulbus continues to grow, this will force the single heart tube to slowly _______.

Answer 4

Bend anteriorly and to the right

Question 5

Producing the ______ on the outside leads to the ______ on the inside.

Answer 5

Bulboventricular sulcus

Fold/flange

Question 6

With the increasing size of the heart tube and continuation of the folding, this will position the _____ and the ______.

Answer 6

Position the truncus and the conus

Question 7

With heart folding and moving ______ and to the _____, this positions the ______ to the ____.

Answer 7

Anteriorly and to the right

Left ventricle to the left

Question 8

With the expansion of the _______ on the right side of the cavity, the _______ moves up and back to now lie within the __________.

Answer 8

Bulbus cordis
Primitive atria
Pericardial cavity

Question 9

The _____ is also repositioned, this forms the __________ between the ____ and _______.

Answer 9

A-V canal
Only communication
Atria and the LV

Question 10

The __________ is growing and dilating and is acquiring a larger lumen.

Answer 10

Primitive left ventricle

Question 11

The junction of the _____ and the _____ will become the ____________ .

Answer 11

LV and the bulbus cordis

Primary interventricular foramen

Question 12

The small right and left _______ dilate considerably to form a large ___________.

Answer 12

Primitive atria

Common atrium

Question 13

At this point ______ start to appear along the ventral borders of the heart tube, proximal to and distal from the ____________ in the _______ and the ________.

Answer 13

Diverticula; Interventricular foramen; Early ventricle; Bulbus cordis.

Question 14

1/3 of the ______ will become the _____ .

The embryo is now _____.

Answer 14

Bulbus cordis; Right ventricle

25 days old

Question 15

What do diverticulum form?

Answer 15

Trabeculation

Question 16

As the heart grows, what gets pulled up into the pericardial cavity and relocated at the back of the atria?

Answer 16

The sinus venosus

Question 17

What does the left sinus horn help to form?

Answer 17

The coronary sinus and gets incorporated into the LA.

Question 18

What does the right sinus horn help to form?

Answer 18

The IVC, the valves of Eustachii and Thebesii

Question 19

The SVC is formed by the ______ .

Answer 19

Cardinal veins

Question 20

What does the growth of the common atria do to the paired sinus venosus?

Answer 20

It draws them up into the pericardial cavity and incorporates them together.

Question 21

To what do the right and left sinus horns attach?

Answer 21

The sinus venosus

Question 22

What do the right and left sinus horns give rise to?

Answer 22

The cardinal veins, the vitelline veins, and the umbilical veins.

Question 23

By approximately day 25, the Bulbus cordis has three parts (or areas). They are ________ , ________ , and ___________ .

Answer 23

The Truncus arteriosus
The Conus cordis
The Primitive RV

Question 24

Clusters of _________ cells appear in the mesenchyme of the _________ Mesoderm.

Answer 24

Angiogenic

Splanchnopleuric

Question 25

The _______ ends of the lateral endocardial tubes eventually make contact with the _______ _________ and the _________ __________. Thus, determining the venous pole of the heart.

Answer 25

1. Caudal
2. Vitteline Veins
3. Umbilical Veins

Question 26

The forebrain grows rapidly and takes the entire ________ _______ into it.

Answer 26

Buccopharyngeal Membrane

Question 27

The growth of the forebrain / neural plate cause the ______________ to disconnect with the _______________. This creates the _____________ .

Answer 27

1. Dorsal Aortas
2. Endocardial Tubes
3. Aortic Arches

Question 28

The Splanchnopleuric Mesodermal tissue surrounding the Endocardial Tubes splits into three layers. They are:

Answer 28

1. Cardiac Jelly
2. Densely nucleated cells
3. Flat mesothelial cells

Question 29

Only the _____ part of the heart tube has a thick layer of cardiac jelly surrounding it.

Answer 29

Bulboventricular