The nasal cavity and the oral cavity are separated from each other by the:

Cornea transplant in humans is almost never rejected. This is because

Two friends are eating together on a dining table. One of them suddenly starts coughing while swallowing some food. This coughing would have been due to improper movement of

Identify $X$ from the figure.

In the human respiratory system,the conducting zone extends from $:-$

'$XX$' is a part of the respiratory system that contains $C$-shaped rings of hyaline cartilage. '$XX$' is lined with ciliated,pseudostratified columnar epithelium. Identify '$XX$'.