Gaseous Exchange and Transport in Animals - 2

The difference in partial pressures of gases results in diffusion of gases through the respiratory membrane. Diffusion occurs when there is a difference between partial pressures of alveolar air and blood.

Gaseous exchange takes place by diffusion across the thin epithelial lining of respiratory cells.

The respiratory centre is located in the medulla oblongata. It consists of both inspiratory and expiratory centres.

Chloride shift is the movement of chloride ions from plasma into red blood cells as a result of the transfer of carbon dioxide from tissues to the plasma, a process that serves to maintain blood pH and electrical balance.

In both the lungs of an adult, there are about 300 million alveoli.

Chemoreceptors are located outside CNS and are responsive to changes in blood O₂, CO₂ and hydrogen ion concentration.

This is the normal breathing rate.

Pleurisy is caused by inflammation of the linings around the lungs (the pleura). Inflammation of the pleural membrane causes friction during breathing which is quite painful when the swollen membranes rub against each other.

Hering-Breuer reflex happens during nervous control of respiration. It inhibits inspiration by sending impulses to the inspiratory centre to stop inspiration.

It is the normal volume of air which goes in and out of the lungs during an effortless breathing. It is about 500 ml in a normal adult.

Haemocyanin is a copper-containing blue-coloured pigment found in the blood plasma of mollusks.

This is the total lung capacity of a normal man.

The gas with a higher partial pressure diffuses towards the gas with lower partial pressure. Thus, nitrogen would flow towards oxygen side.

One molecule of oxygen can combine with one molecule of haem and haemoglobin molecule has 4 haem molecules.

It is a condition in which breathing rate decreases below normal.