GA1 - development of heart and lungs Flashcards
cardiac muscle develops from the ____ mesoderm surrounding the _____ heart ____
splanchnic; endothelial; tube
____ adhere to one another by special attachements that later develop into intercalated discs
myoblasts
the heart develops from ____
mesoderm
heart begins to develop before the end of the ___ week
third
heart is in the ventral region of the embryo beneath the ___
foregut
a pair of endocardial tubes are formed which then fuse together to form the ___ ___ tube
primitive heart
the heart tube develops into 5 regions:
ventricle, bulbus caordis, atrium, sinus venosus and truncus arteriosus
the cardiac tube bends and reorients so that the sinus venosus and atrium come to lie ____ to the ventricle, bulbus cordis, and truncus arteriosus
superior
contractions of the primitive heart begin by day ___
22
by week __, the interatrial septum forms. interventricular septum also forms
7
the bulbus cordis and truncus arteriosus divide into the ___ and ____ ___
aorta and pulmonary trunk
the _____ and ____ vena cava develop from the venous end of the primitive heart tube
superior and inferior
tetralogy of Fallot
consists of pulmonary stenosis, interventricular septal defect, right ventricular hypertrophy, and an overriding aorta
patent ductus arteriosus
maternal rubella infection; remnant of sixth aortic arch
umbilical artery becomes
medial umbilical ligametn
portal veins become
ligamentum teres hepatis
ductus venosis becomes
ligamentum venorum
80% of baby in utero from R atrium goes to
L atrium
20% of baby in utero blood from L atrium goes to ___ ___ –> ___ ___ –> ___ ___
R ventricle –> pulmonary trunk –> ductus arteriosus
lower respiratory tract is derived from _____; upper 1/3 ofn primitive gut
foregut
trachea and esophagus have a comon origin of ____ ____ ___
tracheoesophageal fistula
lower respiratory tract begins as ____ ____ (lung bud)
respiratory diverticulum
endodermal lining of the tracheobronchial tree is derived from the ____
forgut
the respiratory diverticulum becomes invested by ____ mesoderm as it elongates
splanchnic
Pseudoglanduloar period of lung maturation - __ - __ weeks
6-16
psudoglandular period resembles an ___ gland
exocrine
psudoglandular period - by 16 weeks all major elements of the lung have formed except those involved in ___ ____
gas exchange
Canalicular period of lung maturation - ___-___ weeks
16-26
canalicular period - lumina of bronchi and terminal bronchioles become _____ and lung tissue becomes highly ____
larger; vascular
terminal saccular period of lung maturation - ___ weeks - ____
26 weeks - birth
terminal saccular perior - alveolar ducts give rise to ___ ___ (primordial alveoli)
terminal saccules
terminal saccules are lined by type __ alveolar cells and type ___ alveolar cells
1 and 2
terminal saccular period - sufficient amount of ___ is produced
surfactant
surfactant decreases ____ ___
surface tension
alveolar period - ___ weeks - __ years
32 weeks - 8 years
alveolar period - alveolocapillary membrane becomes sufficiently ___ to allow gas exchange
thin
alveolar period - about ___% of mature alveoli develop postnatally
95
