Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Embryology > Development of the Heart > Flashcards

Development of the Heart Flashcards

1
Q

What are some achievements of early embryonic development

A

The first two weeks created tissues of the future embryo and future placenta…

The third week created the three germ layers

– ectoderm, mesoderm and endoderm

– the primordia of all tissues

The fourth week created a recognisable body form and the mesoderm began to organise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the positioning of the cardiogenic area prior to folding

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does lateral and cephalocaudal folding of the heart achieve?

A

Lateral folding
– Creates a heart tube

Cephalocaudal folding
– Brings the tube into the thoracic region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
A

Pair of heart tubes pushed together form primitive heart tube (lateral folding).

and then pushed into pericardial cavity (cephalocaudal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is primitive heart tube held in pericardial cavity?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the structure of the primitive heart tube

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the initial looping of the primitive heart tube

A

Continued elongation results in bending – begins ~d23, complete ~d28

• Cephalic portion
– ventrally, caudally & to the right

• Caudal portion
– dorsally, cranially & to the left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does looping achieve, with respect to inflow and outflow?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the general outcomes of looping?

A

-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Label the heart as it would look on day 28

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does the atrium communicate with the ventricle, following looping?

A

via atrioventricular canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the development of the sinus venosus

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Give a general overview of the development of the atria

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the development of the left atirum

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is the oblique sinus formed?

A

Oblique pericardial sinus formed as left atrium expands absorbing the pulmonary veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe fetal circulation

A

Lungs are non-functional

Receives oxygenated blood from mother via placenta and umbilical vein

By-passes the lungs

Returns to the placenta via umbilical arteries BUT the change in circulation must happen immediately

17
Q

Describe shunts in the foetal circulation

A
18
Q

How are the aortic arches formed?

A

4th arch

R = proximal part of R subclavian A

L = arch of aorta

6th arch = “pulmonary arch”

R = R pulmonary artery

L = L pulmonary artery & Ductus Arteriosus

19
Q

What are the recurrent laryngeal nerves?

A

Each aortic arch has a corresponding nerve.

The nerve corresponding to the 6th is the recurrent laryngeal nerve (br vagus, CN X)
– right descends to T1-T2, & left descends to T4-T5

Two factors influence the course of the nerve on left & right sides

– caudal shift of the developing heart & expansion of the developing neck region

– the need for a fetal shunt between PT & aorta

20
Q

What happens as the heart “descends”, with regards to the aortic arches?

A

The aortic arches are remodelled to create the mature disposition.

As the heart “descends” the nerve hooks around the 6th aortic arch and “turns back on itself”, the left recurrent laryngeal nerve becomes hooked around the shunt between the PT & aorta

21
Q

What are endocardial cushions?

A

Endocardial cushions – developing in the atrioventricular region

Divide the developing heart into right & left channels

22
Q

Describe the process of atrial septation

A

Septum primum grows down towards the fused endocardial cushions.

The ostium primum is the hole present before the septum primum fuses with the endocardial cushions.

Before ostium primum closes, a second hole, the ostium secundum appears in the septum primum (via apoptosis)

Finally a second crescent shaped septum, the septum secundum grows; the hole in the septum secundum is the foramen ovale.

23
Q

Describe remnants of atrial embryonic development

A

Both left & right atria have components derived from the primitive atrium (i.e. auricles)

The right atrium absorbs the sinus venosus

The left atrium sprouts the pulmonary vein then

grows to absorb it and its first 4 branches

The fossa ovalis is the adult remnant of the shunt used in utero to by-pass the lungs

24
Q

What are the components of the ventricular septum?

A

Ventricular septum has 2 components:

– Muscular

– Membranous

• Muscular portion forms most of the septum and grows upwards towards the fused endocardial cushions

25
Q

How is the primary interventicular foramen formed?

A

Muscular portion grows upwards towards the endocardial cushions leaving a small gap, the 1° interventricular foramen

26
Q

How is the primary interventricular foramen formed?

A

Membranous portion of the interventricular septum formed by connective tissue derived from endocardial cushions to “fill the gap”

27
Q

Describe septation of the outflow tract

A

Endocardial cushions also appear in the TA. As they grow towards each other they twist around each other they form a spiral septum

28
Q

Describe the differences in foetal circulation and circulation post-birth?

A
29
Q

How is the foramen ovale closed at birth?

A
30
Q

What happens to the fetal shunts?

A
31
Q

What are the differences between the foetal heart and the developed heart?

A

Embryology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions