NM705 - STUDY GUIDE EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
Canalicular Period
Lumina of bronchi and the terminal bronchioles become larger and lung tissue
becomes ______________.
Highly vascular.
_____ weeks: primordial alveolar ducts (terminal sacs):
24.
________ possible by end of this stage (lung tissue well vascularized).
Respiration.
24-26 weeker may survive if given intense care, but die d/t __________ and other
system immaturity.
Respiratory.
Terminal Saccular Period
More terminal sacs develop and their __________ becomes very thin.
Epithelium.
__________ begin to bulge into sacs.
Capillaries.
Contact between ___________ and __________ cells establishes blood-air barrier,
which permits adequate gas exchange.
Epithelial and endothelial.
,______ weeks: terminal sacs lined by squamous epithelial cells of endodermal
origin.
26.
Type I pneumocytes:
Across which gas exchange occurs.
Type II pneumocytes:
Secrete pulmonary surfactant.
Surfactant:
- Facilitates expansion of terminal sacs.
- Production varies in fetuses of different ages.
- Begins by 20-22 weeks.
- Present in small amounts in premature infants.
- Reaches adequate amount in late fetal period.
- Antenatal corticosteroids and postnatal surfactant replacement therapy increase
survival rate.
Alveolar Period
Thinned walled terminal sacs (future alveolar ducts) separated by
_______________.
Loose connective tissue.
Alveolocapillary membrane thin enough to allow ______ exchange.
Gas.
Transition from placental gas exchange to __________ gas exchange:
Autonomous.
, Autonomous gas exchange:
- Production of surfactant in alveolar sacs.
- Transformation of lungs into gas-exchanging organs.
- Establishment of parallel pulmonary and systemic circulations.
____% of mature alveoli develop in postnatal period.
95.
Alveolar development largely complete by _______ of age.
3 years.
Fetal breathing movements occur before birth:
- Cause aspiration of some amniotic fluid into lungs.
- Movement stimulate lung development.
- Breathing movement increase as delivery approaches.
Look at the phenomena that stimulates the neonate to take his/her first breath.
Differentiate between the biochemical and mechanical events.
Biochemical
Relative hypoxia at end of labor and physical stimuli, such as cold, gravity, pain,
light, noise cause:
Excitation of respiratory center.
Release of ________ pressure at birth may help stimulation.
Thoracic.
Squeezing of thorax in last minute of second stage labor, in birth canal help to:
Extrude some upper airway fluid.
First breath:
COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
Canalicular Period
Lumina of bronchi and the terminal bronchioles become larger and lung tissue
becomes ______________.
Highly vascular.
_____ weeks: primordial alveolar ducts (terminal sacs):
24.
________ possible by end of this stage (lung tissue well vascularized).
Respiration.
24-26 weeker may survive if given intense care, but die d/t __________ and other
system immaturity.
Respiratory.
Terminal Saccular Period
More terminal sacs develop and their __________ becomes very thin.
Epithelium.
__________ begin to bulge into sacs.
Capillaries.
Contact between ___________ and __________ cells establishes blood-air barrier,
which permits adequate gas exchange.
Epithelial and endothelial.
,______ weeks: terminal sacs lined by squamous epithelial cells of endodermal
origin.
26.
Type I pneumocytes:
Across which gas exchange occurs.
Type II pneumocytes:
Secrete pulmonary surfactant.
Surfactant:
- Facilitates expansion of terminal sacs.
- Production varies in fetuses of different ages.
- Begins by 20-22 weeks.
- Present in small amounts in premature infants.
- Reaches adequate amount in late fetal period.
- Antenatal corticosteroids and postnatal surfactant replacement therapy increase
survival rate.
Alveolar Period
Thinned walled terminal sacs (future alveolar ducts) separated by
_______________.
Loose connective tissue.
Alveolocapillary membrane thin enough to allow ______ exchange.
Gas.
Transition from placental gas exchange to __________ gas exchange:
Autonomous.
, Autonomous gas exchange:
- Production of surfactant in alveolar sacs.
- Transformation of lungs into gas-exchanging organs.
- Establishment of parallel pulmonary and systemic circulations.
____% of mature alveoli develop in postnatal period.
95.
Alveolar development largely complete by _______ of age.
3 years.
Fetal breathing movements occur before birth:
- Cause aspiration of some amniotic fluid into lungs.
- Movement stimulate lung development.
- Breathing movement increase as delivery approaches.
Look at the phenomena that stimulates the neonate to take his/her first breath.
Differentiate between the biochemical and mechanical events.
Biochemical
Relative hypoxia at end of labor and physical stimuli, such as cold, gravity, pain,
light, noise cause:
Excitation of respiratory center.
Release of ________ pressure at birth may help stimulation.
Thoracic.
Squeezing of thorax in last minute of second stage labor, in birth canal help to:
Extrude some upper airway fluid.
First breath:
