Development of the respiratory System

Question 1

What happens in Week 3 embryonic development

Answer 1

Oropharangeal membrane forms on the dorsal surface of the anterior region.

cloacal membrane forms on the dorsal surface of the posterior region.

Question 2

What happens to to the oropharyngeal membrane in week 4

Answer 2

The oropharngeal membrane breaks down in week four to connect to the oral cavity to the pharynx and the GI tract.

Question 3

What happens to the cloacal membrane

Answer 3

It breaks down forming the openings of the anal, urinary and reproductive tract.

Question 4

What happens to the embryonic folding in week 4

Answer 4

Causes unequal grownths rates at different parts.

Question 5

What does folding in the medial plane give

Answer 5

Head and tail

Question 6

What does the lateral folds form

Answer 6

coelom and pinches off the yolk sac giving rise to the primitive gut.

Question 7

What is the primitive gut make up of

Answer 7

Foregut, the midgut and the hind gut

Question 8

What does folding cause

Answer 8

It cause the pharyngeal arches to develop on either side of the head and internal pharngeal pouches.

Question 9

When does the lung bud appear and what stage

Answer 9

Week 4 the lung bud and respiratory diverticulum appear as outgrowths from the ventral wall of the foregut.

Question 10

What happens to the lung bud in its early staged.

Answer 10

Has a similar opening to the foregut but as it starts to extend it becomes separated from the foregut by the oesophageal rises.

Question 11

What does the oesophageal ridges fuse with

Answer 11

They fuse with oesophageal septum which then divides the foregut into a dorsal region which is the oesophagus and the ventral region which is the trachea.

Question 12

What is the lining of larynx made up of

Answer 12

Endodermal

Question 13

What is the lining of the muscles and cartilage made up of

Answer 13

Mesenchymal cells

Question 14

Where do mesenchymal cells arise from

Answer 14

4th and 6th pharyngeal arches.

Question 15

What do the pharyngeal arches differentiate into

Answer 15

Thyroid, arentonid and carotid cartilages.

Question 16

How are mesenchymal cells used to develop the larynx

Answer 16

They divide inducing the larnageal opening to change from a simple split to a T Shaped opening.

Question 17

What happens to laryngeal cartilages

Answer 17

they form the laryngeal epithelium which proliferates and temporal blocks the lumen of the deverticulum.

Question 18

How are the trachea and bronchi developed.

Answer 18

The diverticulum separated from the foregut forming two lateral branches to form the right and left primary bronchi by week 5

Question 19

How are the lungs developed

Answer 19

pericardioperitineal canals are found either side of the foregut and they fill.

formation of the type 1 and type 2 cells form.

Question 20

what is oesophageal atresia and tracheosesophageal fistula

Answer 20

Abnormal portioning of oesophagus and the trachea.

Oesophageal atresia the oesophagus terminates in. a blind ended passage

TEF abnormal openings forms between the oesophagus and the trachea.

Question 21

What are congenital cysts

Answer 21

Abnormal budding of the diverticulum, resulting gin dialled and poorly vascualrised terminal or larger bronchioles.

Question 22

What is respiratory distress syndrome

Answer 22

Insufficent quantities of surfactant are produced.

Most common causes of death in premature infants.
Collapse alveoli may become filled with a protein rich fluid and may from what ae known as hyaline membranes.