Questions All Answered Correct 2025.
Pulmonary Ventilation - Answer Mechanics of breathing in and out
Inspiration and Expiration
External Respiration - Answer Exchange of gases between the alveoli and the capillaries of the
lungs
What is happening in external expiration - Answer CO2 moves out of blood O2 moves into
blood
Internal Respiration - Answer Exchange of gases btwn capillaries and tissue
What is happening in internal respiration - Answer CO2 moves into blood from tissues
O2 moves out of blood into tissues
Pneumothorax - Answer Loss of negative pressure btwn the pleura due to air entering pleural
cavity
Leads to actelecstasis: collapse or partial collapse of the lung
Passageway of air - Answer external nare - nasal cavity - pharynx - larynx -trachea - primary
bronch- secondary bronchi - tertiary bronchi - bronchiole - alveolus
Significance of the Epiglottis - Answer Made of elastic cartilage
Opens when we breathe
Closes when we swallow
Bronchioles - Answer Epithelium transitions from pseudostratified to simple columnar to
simple cuboidal
Surrounded by a layer of
, Sympathetic NS: dilates bronchioles
Parasympathetic NS: constricts bronchioles
Controls resistance of airflow and the distribution of air in the lungs
Significance of the cartilage rings of the trachea - Answer Made of hyaline cartilage
1.) allows the esophogus to expand anteriorly
2.) give support to the trachea
Significance of the ciliated epithelium of the trachea - Answer Cilia beats towards the mouth
(mucociliary escalator) move debris toward the pharynx
Alveolus - Answer Made of simple squamous epithelium (air sac)
Respiratory zone: only place that air is exchanged
Septal cell - Answer Type II alveolar cell that secretes an oily secretion (surfactant) that works
to reduce the surface tension in the alveolus and keep the alveoli from collapsing
Respiratory membrane: histological layes oxygen must pass in order to enter the blood - Answer
a.) simple squamous epithelium of alveolus (type I cells)
b.) fused basement membrane of the alveolus and the capillary
c.) simple squamous epithelium of capillay (endothelium)
Characteristics of O2 and CO2 - Answer Nonpolar (fat-soluble) therefore can easily move
across cell membrane through diffusion
Inspiration - Answer Inhalation (active process)
diaphragm contract, external intercoastals expand ribcage
Lung volume increase, pressure decrease= air flows into lungs
What nerve is involved - Answer Phrenic nerve