Test Questions All Answered Correct
(2025) Updated.
O2 pathway - Answer environment air --> lungs --> blood --> tissue --> mitochondria
CO2 pathway - Answer mitochondria --> tissue --> blood --> lungs --> environment air
external respiration - Answer exchange of gas between the air in the lungs and the blood
gas transport by blood - Answer transport of oxygen to the body cells and the return of carbon
dioxide
internal respiration - Answer exchange of gases between blood and body cells
cellular respiration - Answer use of oxygen in cell processes and the production of CO2
upper airways - Answer nose, mouth, pharynx and vocal cords
Functions of Upper Airways: - Answer 1. Warm the air to protect core temperature
2. Add water vapor to the air to prevent lungs from drying out
nose - Answer - divided into superior, middle and inferior turbinate = high surface area
- lined with goblet cells that are ciliated and secrete mucus
sinuses - Answer surround the nasal cavity; ciliated and help move mucus
Lower airways - Answer trachea, bronchi, terminal bronchioles
Function of Lower Airways: - Answer 1. Distribute air to terminal sacs
2. Defense of the lungs from infection and irritation
, PCL - Answer regulates balance of water to keep mucus fluid
Alveoli - Answer Terminal air sacs that constitute the gas exchange surface of the lungs.
Physical Characteristics of Upper Airways: - Answer lined with tracheal cartilage and smooth
muscle
Physical Characteristics of Lower Airways: - Answer only lined by smooth muscle; too thick to
allow diffusion of gas
Ventilation of the Lung: - Answer done by changes in pressure and volume controlled by the
diaphragm and intercostal muscles of the chest
diaphragm - Answer innervated by the phrenic nerve
intercostal muscles - Answer innervated by intercostal nerves
parietal plura - Answer lines the inside of the thoracic cavity
visceral pleura - Answer outside lining of the lungs; very delicate
pleural cavity - Answer fluid-filled space between the parietal and visceral pleura; maintained
by negative pressure which prevents the lungs from pulling away from the chest cavity
Pores of Kohn - Answer alveolar pores that connect alveoli to each other
Type I alveolar epithelial cells - Answer very thin and lines alveoli; structural backbone of
alveoli
Type II alveolar epithelial cells - Answer thicker, very few and spaced out; secrete pulmonary
surfactant