Embryology Flashcards

1
Q

Define Fetus

A

unborn offspring that develops from an embryo

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

Define neonate

A

A baby that is less than 4 weeks old

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

Define infant

A

Infancy is the period from birth until 2 years of age

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

Define zygote

A

fusion of egg and sperm

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

What does the zygote become once there are more than 16 cells?

A

Morula

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

When does the yolk sac develop?

A

approximately 3 weeks after implantation

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

What are the 3 layers of the blastocyst?

A
  1. Ectoderm
  2. Endoderm
  3. Mesoderm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is gastrulation?

A

An early developmental process in which an embryo transforms from a one dimensional layer of epithelial cells and reorganizes into a multilayered and multidimensional structure

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

What group of cells do the lungs originate from?

A

the endoderm

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

Which portion of the gut tube do the lungs come from?

A

The lungs, esophagus, trachea and respiratory tract derive from the midgut

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

What are the 5 stages of fetal lung development?

A
  1. Embryonic
  2. Pseudoglandular
  3. Canalicular
  4. Saccular
  5. Alveolar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the time frame for embryonic lung development?

A

0-8 weeks

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

What is the time frame for pseudoglandular lung development?

A

8-16 weeks

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

What is the time frame for canalicular lung development?

A

16-26 weeks

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

What is the time frame for saccular lung development?

A

26-36 weeks

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

What is the time from for alveolar lung development?

A

36+

17
Q

When are fetal breathing movements detected?

A

Can be detected as early as 10 weeks

18
Q

When are fetal breathing movements strong, organized and consistent?

A

30-40 weeks

19
Q

T/F: Fetal lungs are collapsed

A

False, fetal lungs are fluid filled

20
Q

How much fluid is produced by fetal lungs per day?

A

250-300 ml

21
Q

What occurs in the embryonic stage of lung development?

A

Lung buds, trachea, bronchi and central bronchial arteries are formed

22
Q

What occurs in the pseudoglandular stage of lung development?

A
  1. Formation of terminal bronchioles
  2. branching of bronchopulmonary trees as far as terminal bronchioles
  3. Formation of Cilia
  4. Mucus production
  5. Vascular branching of arteries and veins alongside airways
23
Q

When do the Cilia form?

A

in the pseudoglandular stage of lung development

24
Q

When are the terminal bronchioles formed?

A

In the pseudoglandular stage of lung development

25
Q

What occurs in the Canalicular stage of lung development?

A
  1. Development of primitive acini
  2. Appearance of Type 1 and 2 pneumocytes with lamellar bodies
  3. Surfactant production
  4. Formation of air blood barrier
26
Q

T/F: Respiration is possible in the pseudoglandular stage?

A

False

27
Q

T/F: Respiration is possible in the canalicular phase

A

True

28
Q

What occurs in the saccular stage?

A
  1. Formation, growth and branching of terminal saccules
  2. Growth in number of lamellar bodies
  3. Increase in Surfactant production
  4. Growth of capillary networks around saccules
  5. Formation of conducting and respiratory bronchioles completed
29
Q

In what stage do the capillary networks begin to form around saccules?

A

Saccular stage

30
Q

What occurs in the alveolar stage?

A
  1. Formation and maturation of alveoli
  2. Increased growth in diameter and number of alveoli
31
Q

At what stage is extrauterine viability possible and why cant it occur sooner?

A
  1. Canalicular
  2. The fetus is not viable because surfactant production has not begun, the fetus is incapable of respiration, and the airways are not developed enough yet
32
Q

Describe type 1 pneumocytes

A
  1. Squamous cells
  2. thin for gas exchange/diffusion
  3. 97% of alveolar surface area
33
Q

Describe type 2 pneumocytes

A
  1. Cuboidal cells
  2. Production, storage, secretion and reuse of surfactant
  3. Houses lamellar bodies which store surfactant
34
Q

How can we assess fetal lung development?

A
  1. L/S ratio
  2. Lamellar body Count
  3. PG?
  4. PC/DPPC
35
Q

What aspects can stimulate surfactant secretion?

A

Andosine
Mechanical stretch
Hormones

36
Q

What are the proteins that make up surfactant?

A
  1. DPPC
  2. Protein A (SP-A)
  3. Protein D (SP-D)
  4. Protein B SP-B)
  5. Protein C (SP-C)
37
Q

What is the most abundant phospholipid in surfactant?

A

DPPC aka Lecithin

38
Q

What is the function of protein A?

A
  1. Regulates synthesis and secretion of phospholipids
  2. Promotes bacterial and viral clearance
39
Q

What is the function of protein D

A

Promotes bacterial and viral clearance