E: Heart

Question 1

The heart has 2 atria that are ___ chambers

Answer 1

receiving

Question 2

The heart has 2 ventricles that are ___ chambers

Answer 2

ejecting

Question 3

The right side of the heart receives ___ blood –> ___

Answer 3

deoxygenated blood

ejects to lungs

Question 4

The left side of the heart receives ___ blood –> ___

Answer 4

oxygenated blood

ejects to body

Question 5

The cardiovascular system appears mid-week __; becomes function during week __

Answer 5

appears midweek 3

functional week 4

Question 6

What is one of the very first organ systems to develop in embryo?

Answer 6

cardiovascular system

Question 7

What are the 4 main stages of heart shapes during development?

When do they each appear?

Answer 7

1. cardiac crescent - day 15
2. heart tube - day 21
3. pre-septated looped heart day 28
4. four chamebred heart - day 50

Question 8

Existing blood islands unite and form ____

Other blood islands appear and will form ___

Answer 8

existing blood islands uniting – ENDOCARDIAL TUBES (2) on either side

new blood islands – DORSAL AORTAE (2) on either side

Question 9

Lateral body folding causes what change in endothelial tube?

Answer 9

lateral sides of endothelial tube fold in ventrally and medially

Question 10

When lateral sides of the endothelial tube fuse in the midline, this forms the _____

(lateral sides fold inward during lateral body folding)

Answer 10

primordial heart tube

Question 11

Initially, the heart tube is attached to the dorsal side of the pericardial cavity via ____

Answer 11

dorsal mesocardium

Question 12

What is the dorsal mesocardium?

What happens to it?

Answer 12

initially holds the heart tube to the dorsal side of the pericardial cavity

The middle of it disappears and creates the transverse pericardial sinus

Question 13

How is the transverse pericardial sinus created?

Answer 13

the middle part of the dorsal mesocardium disappears

Question 14

The primordial heart tube just after lateral folding is __ layers.

Name them

Answer 14

3 layers
endocardium
myocardium
epicardium (visceral pericardium)

Question 15

___ folding is responsible for reposition the heart tube

Answer 15

sagittal (cranial-caudal)

Question 16

Pre-sagital folding, the heart tube is

__ to oropharyngeal membrane
__ to pericardial cavity

Answer 16

cranial to oropharyngeal membrane

ventral to pericardial cavity

Question 17

Post-sagittal folding, the heart tube is

__ to oropharyngeal membrane
__ to pericardial cavity
__ to foregut
__ to septum transversum

Answer 17

caudal to oropharynegal membrane

dorsal to pericardial cavity

ventral to foregut

rostral to septum transversum

Question 18

The heart tube forms 5 initial dilations. What are they?

Answer 18

1. truncus arteriosus
2. bulbus cordis
3. primitive ventricle
4. primitive atrium
5. sinus venosus

Question 19

Truncus arteriosus becomes ____

Answer 19

aorta and pulmonary arteries

Question 20

Bulbus cordis becomes ___

Answer 20

outlet of the ventricles

Question 21

Primitive ventricle becomes ___

Answer 21

inlet of the ventricles

Question 22

Primitive atrium becomes ___

Answer 22

right and left atrium

Question 23

Sinus venosus becomes ___

Answer 23

part of the right atrium (where we receive blood)

Question 24

Describe blood flow in the primitive heart tube

Answer 24

caudal to cranial

Question 25

Tubular heart undergoes ___ handed looping

Answer 25

right

Question 26

After tubular heart undergoes RIGHT handed looping, this results in a __ shaped heart With an apex pointing ___

Answer 26

U apex pointing left inferior

Question 27

During right handed looping... primitive ventricles move ____ primitive atria move ___

Answer 27

ventricles move VENTRAL and RIGHT atria move DORSAL and LEFT

Question 28

Sinus venosus receives ___ bloood

Answer 28

venous

Question 29

Sinus venosus receives venous blood from ____

Answer 29

right and left sinus horns

Question 30

Each sinus horn receives venous blood from what 3 structures

Answer 30

vitteline veins umbilical veins common cardinal veins

Question 31

Vitteline veins contain ___

Answer 31

deoxygenated blood from body

Question 32

Umbilical veins contain ___

Answer 32

oxygenated blood from mother

Question 33

Common cardinal veins contain ___

Answer 33

deoxygenated blood from body wall, head, neck

Question 34

Blood flow to the heart (through sinus venosus) gradually shifts to _____ side

Answer 34

right side

Question 35

Because of gradual shift in sinus venosus, which side is larger than the other?

Answer 35

right sinus venosus is larger than left

Question 36

What is the remnant of the left side of sinus venosus after remodeling?

Answer 36

coronary sinus is the remnant also = oblique veins of left atrium

Question 37

What is the coronary sinus

Answer 37

the remnant of the left side of sinus venosus

Question 38

Wha tis the oblique vein of left atrium

Answer 38

small remnant of left side of sinus venosus (can't see in lab)

Question 39

How is the right side of sinus venosus incorporated into the rest of the heart?

Answer 39

incorporated into right CAUDAL/DORSAL part of RIGHT ATRIAL WALL

Question 40

When right side of sinus venosus is incorporated into the dorsal/caudal part of right atrial wall, how does this displate part of the heart?

Answer 40

displaces the original right half of primitive atrial wall farther to the right

Question 41

_____ is the name for the portion of the right atrium containing the right part of sinus venosus

Answer 41

sinus venarum

Question 42

What is the sinus venarum?

Answer 42

the portion of the right atrium consisting of incorporated sinus venosus

Question 43

Where does septum primum develop?

Answer 43

roof of atrium

Question 44

Septum primum is a thin, ___-shaped membrane

Answer 44

moon shaped

Question 45

Septum primum extends towards the ____ in the AV canal

Answer 45

endocardial cushions

Question 46

Where is ostium primum located?

Answer 46

ostium primum aka foramen primum located below the endocardial cushions

Question 47

When septum primum hits the endocardial cushions, what happens?

Answer 47

ostium primum closes ostium secundum in septum primum begins forming septum secundum begins forming

Question 48

When perforations of septum primum begin to form, this forms ___

Answer 48

ostium secundum

Question 49

Septum secundum develops where?

Answer 49

roof of atrium, slightly to the right of septum primum

Question 50

Septum secundum develops as what else is happening?

Answer 50

as holes of septum primum are forming ostium secundum

Question 51

Septum secundum develops in what orientation?

Answer 51

inferiorly

Question 52

Septum secundum develops an opening that forms ___

Answer 52

foramen ovale

Question 53

All foramen allow for blood flow to be shuttled between ___

Answer 53

right and left atria in development

Question 54

Septum primum is pressed against septum secundum and adheres to it. Why does this happen? What happens as a result?

Answer 54

At birth, left atria is filled w/ blood --> pressure against septum primum pushes it against septum secundum Foramen ovalis becomes fossa ovalis

Question 55

When does septation of the av canal occus?

Answer 55

week 4

Question 56

____ develop on each side of the AV canal, causing septation of the canal

Answer 56

4 endocardial cushions

Question 57

the 4 endocardial cushions are masses of ___

Answer 57

mesenchymal tissue

Question 58

the 4 endocardial cushions aid in the formation of the ____

Answer 58

orifices for the mitral and tricuspid valves of the heart

Question 59

When has the AV canal officially been separated into a RIGHT and LEFT av canal?

Answer 59

when the superior and inferior endocardial cushions fuse togehter

Question 60

The primitive ventricles begin to expand, and ultimately the ___ walls fuse together

Answer 60

medial

Question 61

When the medial walls of primitive ventricles fuse together, this forms ____

Answer 61

muscular interventricular septum

Question 62

where is the interventricular foramen located relative to the muscular interventricular septum?

Answer 62

interventricular foramen is just above the muscular interventricular septum

Question 63

What closes the interventricular foramen?

Answer 63

an outgrowth of endocardial cushions

Question 64

Complete closure of the interventricular formaen creates the formation of ____

Answer 64

membraneous part of interventricular septum

Question 65

When does partiitoning of the outflow tracts take plcae?

Answer 65

week 5

Question 66

Partitioning of the outflow tracts: ___ migrate to truncus arteriosus and bulbus cordis

Answer 66

neural crest cells

Question 67

Partitioning of the outflow tracts: neural crest cells migrate to __ and __

Answer 67

truncus arteriosus bulbus cordis

Question 68

Partitionig of the outflow tracts: neural crest cells migrate to truncus arteriosus and bulbus cordis to form ___

Answer 68

truncal ridges and bulbar ridges

Question 69

Truncal ridges and Bulbar ridges under go ____

Answer 69

180 degree spiraling

Question 70

Spiraling of truncal ridges and bulbar ridges results in formation of ____ when the ridges fuse

Answer 70

spiral aorticopulmonary septum

Question 71

Spiral aorticopulomonary septum forms when ___

Answer 71

the truncal ridges and bulbar ridges fuse after spirlaing

Question 72

The spiraling of the truncal and bulbar ridges twist around what structure?

Answer 72

ascending aorta

Question 73

The truncal and bulbar ridges grow inferiorly to contribute to a portion of ___

Answer 73

membraneous Interventricular septum