Devt of Respiratory system

Question 1

In the formation of the primitive gut tube, the embryo folds in two directions. These are?

Answer 1

Cephalodcaudal and lateral folds

Question 2

The primitive gut tube is formed by

Answer 2

A portion of yolk sac lined by endoderm, which is now internalized

Question 3

Development of respiratiory diverticula begins in week

Answer 3

4

Question 4

How foes it develop

Answer 4

Proliferation of the endodermal epithelium of the ventral part of the foregut(laryngotracheal groove) into mesenchyme

Question 5

Respiratory epithelium develops from?

Answer 5

Endodermal tube

Question 6

The rest of resporatory wall develop from?

Answer 6

Sphlanchnic mesoderm surrounding the foregut

Question 7

Diverticulum bifurcates to form

Answer 7

Primary bronchial(lung) buds

Question 8

How are the lung buds separated from the foregut

Answer 8

By two longitudinal ridges closing off communication. Tracheosophageal ridge.
These ridges fuse to form the tracheo oesphageal septum

Question 9

Foregut is then separated into

Answer 9

Dorsal oesophagus and ventral trachea and lung buds

Question 10

Initially, the lung is a space called

Answer 10

Pericardioperitoneal canals

Question 11

Sufficient mature terminal sac are present at end of

Answer 11

Terminal sac

Question 12

Type two aveolar cells secrete surfactant at

Answer 12

End of sixth month

Question 13

What causes the induction of the respiratory tree

Answer 13

An increase in the retinoic levels in the endoderm, which causes an increase in the expression of transcription factor TBX4 in the endoderm
Wnt signaling necessary for the formation of the respiratory tree

Question 14

Tracheomalacia and Bronchiomalacia

Answer 14

Cartilage around them not forming properly

Question 15

Diaphragm is formed by fusion of

Answer 15

Septum transversum
Peripheral rim derived from body wall
Pleuroperitoneal membranes
Dorsal oesophageal mesentry

Question 16

Diaphragm supplied by

Answer 16

Phrenic nerve

Question 17

Level of inferior vena cava, oesophagus, and aorta

Answer 17

8 10 12

Question 18

Stages of development of respiratory system

Answer 18

Embryonic 
Pseudoglandular
Canalicular
Saccular
Alveolar

Question 19

What is polyhydramnios

Answer 19

Baby isn’t swallowing fluid in uterus so fluid stays and becomes really large around baby

Question 20

What influences induction of the development of the respiratory system

Answer 20

Retinoic level in mesoderm increased.
Causes increased expression of transcription factor TBX4 in the endoderm
Wnt signaling necessary for respiratory tree formation

Question 21

Surfactany primarily composed of

Answer 21

Phospholipids

Question 22

Note

Answer 22

Alveolar development is a post natal phenomenon

Question 23

Division of bronchioles continues up to

Answer 23

7th prenatal month. Canalicular phase

Question 24

Sufficient mature terminal sac present at?

Answer 24

End of 7th month

Question 25

How much of alveoli is present at birth

Answer 25

1/6