Heart Development

Question 1

1st sign of a heart, solid horseshoe shaped cluster of cells

Answer 1

Primary heart field

Question 2

Islands will unite and form a horseshoe shaped endothelial lined tube surrounded by myoblasts within the cardiogenic region called…

Answer 2

endocardial tubes

Question 3

Lateral folding creates…

Answer 3

primordial heart tube

Question 4

This repositions the developing heart

Answer 4

Cranial-Caudal folding

Question 5

Attaches the heart tube to the dorsal side of pericardial cavity

Answer 5

dorsal mesocardium

Question 6

Formed when the middle section of dorsal mesocardium disappears

Answer 6

Transverse Pericardial sinus

Question 7

Different sections of developing heart from in–>out (inferior to superior in picture)

Answer 7

Spike A Volley Ball

1. Sinus Venosus
2. Primordial Atrium
3. Promordial Ventricle
4. Bulbus Cordis

Question 8

2 parts that make up the Bulbus Cordis

Answer 8

Truncus Arteriosus and Conus Cordis

Question 9

What does TRUNCUS ARTERIOSUS become?

Answer 9

Pulmonary trunk and aorta

Question 10

What des CONUS CORDIS become?

Answer 10

Outflow tract of ventricles; caudal portion forms Right Ventricle

Question 11

What does PRIMORDIAL VENTRICLE become?

Answer 11

Left ventricle

Question 12

What does PRIMORDIAL ATRIUM become?

Answer 12

Right and left auricles and portions of the atria

Question 13

What does SINUS VENOSUS become?

Answer 13

Coronary sinus and sinus venarum

Question 14

Does the heart look to the right or left?

Answer 14

Right

Question 15

Circulation through the primordial heart (day 30)

Answer 15

Sinus Venosus–Primordial atrium–av canal–left ventricle–IV foramen–Right ventricle–Conus cordis–Truncus arteriosus–aortic sac–pharyngeal arch aa–dorsal aortae

Question 16

Sinus venosus receives venous blood from what 3 paired veins? (Medial to lateral)

Answer 16

1. Vitelline vv
2. Umbilical vv
3. Common Cardinal vv

Question 17

what horn of the sinus venosus becomes larger and why?

Answer 17

Right Horn

Blood flow tot he heart shifts to the right side due to the remodeling of the 3 veins.

Question 18

Left sinus horn becomes what two structures?

Answer 18

1. Oblique veins of the left atrium

2. Coronary Sinus

Question 19

What happens to the right sinus horn?

Answer 19

Becomes incorporated intot the right atrium to form the smooth wall portion

Question 20

What is the name of the entrance formed by the right sinus horn merging with the right atrium?

Answer 20

Sinus Venarum

Question 21

2 ways to form septa of the heart

Answer 21

1. Endocardial cushions (Atria)

2. Merging two expanding portions of the wall (ventricles)

Question 22

Around the end of week 4, a crest of tissue grows from the roof of the common atrium, this structure is called?

Answer 22

Septum Primum

Question 23

Perforations in septum primum form…

Answer 23

ostium secundum

Question 24

Grows just to the right of septum primum and creates what opening?

Answer 24

Septum secundum grows inferior and creates foramen ovale

Question 25

how does foramen ovale close and what does it form?

Answer 25

A change in pressure causes septum primum to adhere to septum secundum creating the FOSSA OVALIS

Question 26

Complete closure of the interventricular foramen is done by what and forms what?

Answer 26

Done by outgrowth of inferior endocardial cushion and forms the membranous part of the interventricular septum

Question 27

• Most common congenital heart defect

* Failure of IV septum to completely form

Answer 27

Ventricular Septal Defect (VSD)