Which of the following phenomena is most likely occurring during ...

[CBme]

Which of the following phenomena is most likely occurring during a child's alveolar stage of lung development?
 
  A)
  Terminal alveolar sacs are developing, and surfactant production is beginning.
  B)
  A single capillary network exists, and the lungs are capable of respiration.
  C)
  The conducting airways are formed, but respiration is not yet possible.
  D)
  Primitive alveoli are formed, and the bronchi and bronchioles become much larger.

Question 2

Following a winter power outage, a client who had been using a home gasoline generator began to experience dizziness and headaches and was diagnosed with carbon monoxide poisoning.
 
  What is the goal of hyperbaric oxygen treatment for carbon monoxide poisoning?
  A)
  To increase the amount of oxygen carried in the dissolved state
  B)
  To increase the production of unbound hemoglobin
  C)
  To stimulate the release of oxygen at the capillaries
  D)
  To remove bound CO from hemoglobin

[nixon_s]

Answer to Question 1

Ans:
B

Feedback:

During the alveolar stage of lung development from late fetal to early childhood, a single capillary network appears, and the lungs are ready to perform respiration. The development of alveolar sacs and production of surfactant are associated with the saccular period, and formation of the conducting airways occurs during the pseudoglandular period. Formation of primitive alveoli takes place during the canalicular period.

Answer to Question 2

Ans:
A

Feedback:

While increased alveolar PO2 improves the oxygen saturation of hemoglobin, carbon monoxide occupies the hemoglobin sites usually available for oxygen. With much of the blood composed, temporarily, of carboxyhemoglobin, it is necessary to rely upon alternate means to deliver oxygen to the tissues. Plasma's normally low carrying capacity for dissolved oxygen can be increased by administration of 100 oxygen in the high atmospheric pressure of a hyperbaric chamber.