Question

Answer the following in detail.

In human beings, what happens to oxygen after it is inhaled through the nose? 

Answer 1

Air rich in oxygen enters the body through the nostrils (nose). From the nose, air enters the phaiynx which leads to the larynx and then trachea (windpipe). From the trachea, it enters the bronchi and enters the lungs. From bronchi, it enters bronchioles and finally the alveoli. The oxygen diffuses through the thin walls of blood capillaries (surrounding) into the blood and combines with hemoglobin to form oxyhemoglobin. The oxygen in the blood is carried to all body cells where internal respiration takes place in a series of chemical reactions and food (in the form of glucose) is converted into carbon-dioxide water and energy in the form of ATP, using the oxygen.