Book lungs are a unique type of respiratory organs that are used for atmospheric gaseous exchange in spiders.

It is the only mode of respiration in earthworms. In cutaneous respiration, the skin is thin, moist and vascular. It acts as a respiratory surface.

It is the middle part of pharynx. It is the continuation of the buccal cavity.

Persons with snoring habit suffer from temporary closure of respiratory tract. It results in apnoea and sleep breaks.

The muscles extend from the tubercles of the ribs behind, to the cartilages of the ribs in front, where they end in thin membranes. These muscles work in unison during inhalation. The internal intercostal muscles relax while the external muscles contract, causing the expansion of the chest cavity and an influx of air into the lungs.

It is the inspiratory capacity of lungs.

After a few divisions, terminal bronchioles give rise to respiratory bronchioles. After a few division, terminal bronchioles gives rise to respiratory bronchioles.

It is the maximum extra volume of air that can be inspired after a normal tidal inspiration.

Vestibular folds are also known as false vocal chords. They are also called venticular folds. They are called false vocal cords because they are not involved in voice production.

It is a special organ of respiratory tract that is present in proximal region of trachea.

It is the inflammation of pleural sacs due to excessive pleural fluid.

At the level of the fifth thoracic vertebra, trachea divides to form a left and right primary bronchi.

It is the largest cartilage. It is broad and C-shaped in outline, with a V-shaped notch on the superior edge. There are two small elongated club-shaped nodules of elastic fibro cartilage which lie above and anterior to corniculate cartilage.

The cells which eliminate particles and microbes reaching the alveoli are called dust cells. These are also known as macrophages.

Breathing or pulmonary ventilation facilitates intake of atmospheric air and expulsion of alveolar air.