Question

The structure which prevents entry of blood into the respiratory tract
(a) Pharynx
(b) Larynx
(c) Glottis
(d) Epiglottis

Answer 1

Hint: The function of the epiglottis is to seal the laryngeal inlet during swallowing and thereby prevent the food and liquid from aspiring into the lungs.

Complete answer:The epiglottis is a cartilaginous flap that stretches in front and over the inlet of the laryngeal, or more accurately the glottidis rima.
The epiglottis has the function of closing the laryngeal inlet during swallowing and thereby blocking the flow of food and liquid into the lungs (aspiration). This is why we can not speak and breathe while swallowing (and shouldn't attempt to do so).
The epiglottis resides in the larynx and is attached to the cartilage of the thyroid and the hyoid bone. The movements are controlled by passive tongue pressure as it moves the food down the pharynx, as well as by aryepiglottic muscle contractions.

So, the correct answer is ‘Epiglottis’

Note: Childhood vaccine can prevent epiglottitis against H. Form B influenza (Hib). To persons living with an unvaccinated child under 4 years of age who is introduced to an adult with H. Influenzae epiglottitis, a prevention drug such as rifampin (Rifadin) is given to all household partners to prevent bacteria from spreading.