Question

describe the respiratory organ of human

Answer 1

Lungs are the main organ of respiratory system.
Hope it helps

Answer 2

Answer:

1. Nose: It’s outermost opening, having a pair of external nares (nostrils) followed by a ridge, the nose. Air  enters through nostrils. The nostrils contain hair which helps in ltering out the dirt of air. Other foreign  particles i.e. germs may lodge on the moist mucous membrane of the nasal passage. The nasal passage  leads internally through the internal nares into the pharynx.

2. Pharynx: From the nasal passage air enters the throat through the pharynx. Pharynx contains the  openings of windpipe (trachea) called glottis and of food passage (oesophagus) called gullet. Between  these two openings, there is a cartilaginous ap, the epiglottis which normally covers the gullet, except  when something is swallowed; when it covers the glottis, so that chewed food only enters in the food pipe.

3. Trachea: The trachea is a pipe like structure, which is as long as the neck of the man. Trachea is covered  by a semi-circular ring like cartilage on its sides and front. At its upper part is Larynx, the sound box. In the  region of the chest, trachea bifurcates into bronchii. Each bronchus enters into the lung of the same side  and there, it further divides into many branches-the bronchioles and ne capillaries each entering into airsacs.

Main respiratory organ: Lungs:

=> Lungs are two in number. These are enclosed in chest box. Each lung has a double wall of pleural  membrane. The outer pleural membrane is in contact with muscles of ribs. Each lung is a spongy bag-like  structure.

=> The inner pleural membrane is raised into a large number of sacs, the air sacs which increase the area for  exchange of gases. These air sacs, are richly supplied with blood vessels.

=> Each air sac looks like a cluster of a number of grapes and consists of a number of balloon-like swelling,  called alveoli. These alveoli are thin, moist membranes and one cell thick layers. They are in close contact  with the extensive capillary network. They act as a functional unit of lungs, in which the exchange of gases  takes place.