The trachea divides into two primary bronchi where the right with respect to the left is:
1. wider
2. longer
3. more horizontally oriented
4. all of the above

The diffusion of gases in lungs occur across the respiratory membrane. Which of the following is incorrect regarding the respiratory membrane?
1. it is the only barrier between the blood and the inhaled gases within each alveolus
2. basement membranes of alveolar type I cells and their adjacent capillaries are fused
3. oxygen cannot diffuse through the membrane and so must be actively transported
4. carbon dioxide diffuses across the membrane from the blood into the alveolar lumen

In normal resting respiration, the active and passive processes respectively are:
1. inhalation, exhalation
2. exhalation, inhalation
3. expiration, inspiration
4. eupnea, hyperpnea

Trachea is invested with incomplete cartilaginous rings. They:
1. serve as a point of attachment for some muscles of expiration.
2. support muscular attachments to the thyroid cartilage and epiglottis.
3. prevent the trachea from collapsing.
4. attach the trachea to the esophagus posteriorly.

Alveoli in the lungs are lined by:
1. a simple squamous epithelium.
2. a pseudostratified ciliated columnar epithelium.
3. a simple cuboidal epithelium.
4. a transitional epithelium.

Lungs are made up of air-filled sacs, the alveoli. They do not collapse even after forceful expiration, because of
1. Residual Volume (RV)
2. Inspiratory Reserve Volume (IRV)
3. Tidal Volume (TV)
4. Expiratory Reserve Volume (ERV)

The partial pressure of oxygen in the alveoli of the lungs is
1. equal to that in the blood
2. more than that in the blood
3. less than that in the blood
4. less than that of carbon dioxide

Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because
1. there is a negative pressure in the lungs
2. there is a negative intrapleural pressure pulling at the lung walls
3. there is a positive intrapleural pressure
4. pressure in the lungs is higher than the atmospheric pressure

Reduction in pH of the blood will
1. reduce the blood supply to the brain
2. decrease the affinity of hemoglobin with oxygen
3. release bicarbonate ions by the liver
4. reduce the heart rate

Name the chronic respiratory disorder caused mainly by cigarette smoking
1. asthma
2. respiratory acidosis
3. respiratory alkalosis
4. emphysema