Question

Explain human respiratory system in short.

Answer 1

air enters through nose goes to lungs gets filtered in alveoli present in lungs in billions of number then the filtered oxygen enters the blood stream through blood capillaries connected to alveoli. Resulting in oxygenating the blood.

Answer 2

$\textbf{Respiration System....}$


→ Pair of nostrils are present in us, which leads to nasal chamber through nasal passage. The nasal chamber opens into nasopharynx Nasopharynx opens into trachea from larynx. 

→ Trachea is a long and straight tube, which divides into bronchi. Each bronchi further divides into primary, secondary and tertiary bronchi which together make bronchioles. Bronchioles give further rise to alveoli. Alveoli  is a thin bag like structure, here exchange of gases takes place.

→ Branching network of bronchi, bronchioles and Alveoli comprises the Lungs. Each lung is covered by a pleural layer. This membrane/layer contain fluid in it, which reduce the friction. 

* Weight of human lungs = 450 gm..

* Trachea = 11 cm long, 2.5 cm wide tube..
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