Respritory System And Thoracic Cavities

Question 1

The laryngotracheal groove and associated structures are comprise mainly of what and from where?

Answer 1

Foregut endoderm from the 6th primitive pharynx arch

Question 2

When does the laryngotracheal groove form

Answer 2

Wk. 4

Question 3

When does the tracheoesophageal folds complete the division into the tracheoseophageal septum

Answer 3

Wk. 5

Question 4

An issue with the tracheoesophageal septum can gives rise to what disease

Answer 4

TEF

Question 5

The laryngotracheal groove is derived from what

Answer 5

Foregut endoderm

Question 6

What is the cartilage of the trachea is derived from

Answer 6

Splanchnic mesoderm

Question 7

What does the epiglottis form from

Answer 7

The hypobranchial eminence

Question 8

What is apoptosed during recanalizationm to allow passage between the vocal chords

Answer 8

Endoderm

Question 9

When does recanalization take place and what does it form

Answer 9

Take place in week 10 and forms laryngeal ventricles and vestibular folds

Question 10

Define laryngeal atresia. When does it occur, what is the clinical significance, and what causes it

Answer 10

Blockage of the upper airway. Also results in an inverted diaphragm and and fetal ascities (accumulation of serious fluid in the peritoneal cavity)

Occurs during the 10th week

Occurs due to a failure of recanalization (failure to apoptos the endoderm)

Baby needs immediate cric to survive

Question 11

Define laryngeal webs. What causes it, what is the clinical significance, and how does it present

Answer 11

Is an incomplete atresia. The glottic opening is closed off with cartilage (endoderm) which fails to apoptose during recanalization

Presents as respiratory distress and stridor

Question 12

Define laryngomalacia

Answer 12

A collapse of the supragolottic structures during inspiration

Is the most common abnormality of the larynx

Question 13

The endoderm of the trachea gives rise to what

Answer 13

Epithelium and glands of the trachea

Pulmonary epithelium

Question 14

The splanchnic mesenchyme of the trachea gives rise to what

Answer 14

Cartilage, connective tissue, and the smooth muscles

Question 15

Define an esophageal atresia

Answer 15

A blind end esophagus - proximal esophagus stops while distal esophagus is joined with trachea via fistula

Happens in 84% of cases

Question 16

Define tracheoesophageal fistula

Answer 16

An abnormal passage between the trachea and the esophagus

Question 17

The bronchi and lungs grow into what

Answer 17

Pericardial peritoneal canals

Question 18

At what week do the primary, secondary, and tertiary bronchi develop

Answer 18

Primary - wk. 5
Secondary - wk. 6
Tertiary - wk. 7

Question 19

What happens during pseudoglandular stage and when is this stage

Answer 19

Terminal bronchioles form
Connective tissue forms

(5 - 17 weeks)

Question 20

What occurs during the canalicular stage and when is it

Answer 20

16 - 25 wks.

Vascularization

Respiratory bronchioles gives rise to primordial alveolar ducts which give rise to terminal sacs (primitive alveoli)

Question 21

What occurs during the terminal sac stage and when is it

Answer 21

24wks - birth

Gas exchange can occur here

Lymphatic capillaries form

Squamous epithelium differentiates into Type I pneumocytes

Secretory epithelial cells give rise to type II pneumocytes

Question 22

What occurs in the alveolar stage and when is it

Answer 22

32 wks - 8yrs

Formation of alveolarcapillary membrane from endoderm and mesoderm

More primitive alveoli form

Mature alvioli form

Question 23

What three things need to happen inorder for good lung development

Answer 23

1. Fetal breathing movement
2. Adequate thoracic space for growth
3. Amniotic fluid

Question 24

Define oligohydramnios

Answer 24

Very decreased amniotic fluid

Pulmonary hypoplasia may result (small lungs)

Question 25

Splanchnic mesoderm gives rise to what in the airway

Answer 25

Cartilage
CT
Smooth muscles

Question 26

Endoderm gives rise to what in the airway

Answer 26

Epithelium and the glands of trachea

Pulmonary epithelium