Breathing and Exchange of Gases Test - 2

Carina is the internal ridge that separates the right and the left bronchi.

The tertiary bronchi enters the bronchopulmonary segment of the lung. Bronchopulmonary segment is the largest segment of a lung lobe.

Asphyxia is a condition of the oxygen starvation due to low atmospheric oxygen or interference with the ventilation. In emphysema, the alveolar walls lose their elasticity and remain filled with air during expiration and, the lungs become permanently inflamed because they have lost their elasticity.Diphtheria is a bacterial infection affecting the upper respiratory tract and, it causes swelling in the throat. Pneumonia is usually a bacterial infection in which the lymph accumulates in the alveoli and the bronchioles.

In the Hamburger's phenomenon, Cl^- ions enter the RBCs in response to the exit of HCO₃^- ions. This helps in maintaining a constant pH of blood and an electrical balance between RBCs and plasma.

Some of the carbon dioxide is transported dissolved in the plasma. Some carbon dioxide is transported as carbaminohemoglobin. However, most carbon dioxide is transported as bicarbonate. About 70% of the total CO₂ produced is carried in the form of bicarbonates in the plasma and the RBCs.

 Coelenterates and flatworms use simple diffusion over their entire body surface for the exchange of gases. Earthworms use a moist cuticle for the exchange of gases. Aquatic arthropods like crustaceans use special vascularised structures called gills for the exchange of gases.

A portion of pharynx is the common passage for food and air.

Larynx helps in sound production and is also called as the sound box.

 Epiglottis covers the glottis during swallowing to prevent the entry of food into the larynx. It is a thin elastic cartilaginous flap.

This is the correct option as the branching network of bronchi, bronchioles and alveoli comprises the lungs.