2401 - Anantomy Resp Histology And Development Flashcards
State the development of the respiratory system
Respiratory (laryngotracheal) diverticulum
State the development of the lining of the trachea, larynx, bronchi and lungs.
Endoderm of diverticulum
What is the development of the nasal cavities?
Endodermal nasal pits.
Note: the pits develops into sacs at 6th week intrauterine life.
State the development of the nasal conchae (superior, inferior and middle conchae).
Lateral wall of nasal cavity.
What is the lining of paranasal sinuses.
Ectodermal.
State the lining of the nose and nasal cavity.
Ectodermal
When does the maxillary and frontal air sinuses develop?
Maxillary - 3 - 4th intrauterine months
Frontal - after 5th or 6th postnatal year
State the functions of the paranasal sinuses.
Contributes to definitive shape of face
Takes weight off skull
Voice resonance
Acts as an air conditioner for inspired air.
Familiarize yourself with the paranasal sinuses
Frontal sinus
Ethmoid sinus
Maxillary sinus
Sphenoid sinus
State the development of the respiratory diverticulum.
Cranial and ventral part of foregut during 4th intrauterine life.
Give the development of the following:
A) trachea
B) larynx
C) cartilage of larynx
D) muscles of larynx
A- laryngotracheal diverticulum
B- laryngotracheal diverticulum
C - mesenchyme of 4th and 6th pharyngeal arches. Epiglottis - hypobranchial eminence.
D- mesenchyme of 4th and 6th pharyngeal arches.
What is the nerve supply of the larynx?
4th (superior laryngeal) and 6th (recurrent laryngeal) nerve.
Give the development of the cartilage, muscle and connective tissue of the trachea.
Splanchnopleuric intraembryonic mesoderm.
What structure separates the trachea from the esophagus?
Trachea- oesophageal septum.
Discuss the stages of maturation of lungs.
Pseudo-glandular stage (5-16 weeks) - Components of respiratory and alveoli are not developed. Fetus can not survive.
Canalicular stage (16- 26 weeks) - a few respiratory and alveoli is developed. Fetus can survive at end of stage
Saccular stage ( 26 weeks - birth) - respiratory and alveoli more developed. Gas exchange occurs. Fetus survives this stage
Alveolar stage (8 months - 8yrs) - surfactant produced at this stage. Free exchanges of gases occur.
