Skin contains pores through which the exchange of gases takes place.

Anaerobic respiration occurs in the absence of oxygen .It yields lesser amounts of ATP than aerobic respiration, which occurs in the presence of oxygen.

Alveoli are the structures present in the lungs to increase its surface area. Residual or remaining air remains there.

Respiratory quotient is the ratio of volume of carbon dioxide produced to the volume of oxygen consumed. It varies with different foods used.

Chemical energy of food is used in respiration to produce oxygen.

Each lung is covered by a pleural membrane externally and turned back on itself to the inside of the thoracic cavity.

At high altitude, RBCs of human blood increase in number to accommodate larger amount of haemoglobin for the increased uptake of oxygen, which is present in lesser amounts at higher altitudes.

Carbon monoxide is the principal gas which is released in the auto mobile exhaust. It creates respiratory problems as it combines with haemoglobin faster than oxygen and it is poisonous too.

Haemoglobin is the respiratory pigment which occurs in the blood of a frog and other vertebrates. It can combine with oxygen and carbon dioxide and helps in their transport inside the body.

In common cold, the lungs are not involved. Only, the nose and nasal passages are involved.

Presence of gills in the tadpoles suggest that frogs or amphibians were evolved from fishes. Metamorphosis in tadpoles changed a tadpole to frog during which gills got lost.

Branchial respiration is the respiration which occurs through gills. It mainly occurs in the aquatic animals, such as fishes.

In yeast, anaerobic respiration occurs, i.e. they respire in the absence of oxygen.

Green plants release oxygen through photosynthesis, which is inhaled by fishes, so they thrive well here.

Buccopharyngeal respiration occurs through the mouth, but when pulmonary respiration, i.e. respiration through lungs occurs, buccopharyngeal respiration stops as buccopharyngeal respiration alone fulfills all the needs of energy.