Respiratory Embryo Flashcards
What is the first indication of lower respiratory growth
Laryngotracheal groove
Where does the laryngotracheal groove arise
From endoderm
on the ventral wall of the foregut
caudal to 4th pharyngeal arch
What does the laryngeotracheal groove elongate to become
Lung (respiratory) bud
which diretion does the lung bud grow and into what layer
inferiorly and ventrally into splanchnic mesoderm
What is the opening of the lung bud tube inferiorly
the inlet of the larynx
What forms the cartilages of the larynx
4th and 6th pharyngeal arches (neruoectoderm)
When does respiratory system development begin
during 4th week
What happens at the end of the 4th week
Lung bud/tube divides into two bronchial buds, which enlarge to form primiary bronchi
What is the difference in size and orientation between bronchi
right one is larger and more vertically ooriented than the left one
What happens in the 5th week
Bronchial buds divide into secondary lobar bronchi
What happens in the seventh week
Secondary lobar bronchi divide into tertiary segmental bronchi
How many segmental bronchi are there per lung
10 in right
8 in left
What is a bronchopulmonary segment
a segmental bronchus and some splanchnic mesenchyme
