Prenatal Lung Development Flashcards
human lung epithelium is derived from which primary layer of an early embryo
endoderm
surrounding mesenchyme (provide support and structure to lung tissue) is derived from which primary layer of an early embryo
mesoderm
human lung development occurs through how many morphological stages
5
why do the 5 morphological stages of human lung development overlap in timing
because different stages happen in different lung regions at the same time
list the 5 morphological stages of human lung development
- embryonic
- pseudoglandular
- canalicular
- saccular
- alveolar -
[5 stages of lung development] embryonic occurs in which weeks post conception
4-7 weeks pcw
[5 stages of lung development] psuedoglandular occurs in which weeks post conception
5-17 pcw
[5 stages of lung development] canalicular occurs in which weeks post conception
16-26 pcw
[5 stages of lung development] saccular occurs in which weeks post conception
26-36 pcw
[5 stages of lung development] alveolar occurs in which weeks post conception
36 pcw - 3 years post birth
[embryonic] the primary left and right lung buds appear from where towards the end of week _ after conception
- foregut endoderm
- week 4
[embryonic] the primary left and right lung buds ____ ________ to set up the overall lobular structure of the lung by end of week _
- branch rapidly
- week 5
[pseudoglandular] the lung continues to grow by
branching morphogenesis
[pseudoglandular] what is laid down and begins to differentiate with cartilage
the airway tree
[pseudoglandular] what muscle and what glands develop
- smooth muscle
- mucous glands
[pseudoglandular] foetal breathing movements begin by what weeks
10-11 weeks after conception
[pseudoglandular] accumulation of lung liquid in foetal lungs is critical for what
lung growth
[pseudoglandular] blood vessel development occurs concurrently with what
epithelial branching
[pseudoglandular] airway epithelium begins to what
differentiate
[canalicular] what happens to existing airways
grow in size
the last stage of branching morphogenesis occurs during which development stage
canalicular
[canalicular] describe the last stage of branching morphogenesis
3 more rounds of epithelial branching occur to produce future alveoli
[pseudoglandular] describe the vessels location
run alongside airways but branch more slowly
[canalicular] the future alveoli develop from what
the most distal epithelial tubes
[canalicular] what happens to the most distal epithalial tubes
- widen into airspaces
- surrounding mesenchyme thins
[canalicular] during this stage of development, close proximity develops between what
capillary networks & regions of the distal epithelial tubes that will form airspaces
[saccular] is marked by the differentiation of what
alveolar epithelial cells
[saccular] what begins due to the differentiation of alveolar epithelial cells
production and secretion of surfactant by type II alveolar cells
[saccular] what happens to the distal airspaces
become thin-walled terminal saccules[s
[saccular] what is the location of the terminal saccules
cluster at the ends of the airways
[saccular] what happens to the terminal saccules
- increase further in size
- become completely wrapped in a capillary bilayer
[alveolar] alveoli form within each ____
airway sac
[alveolar] how are distal saccules subdivided into alveoli
growth of septae from saccular walls
