Which organ system is responsible for protecting the body against infectious agents?

The answer is the immune system.

Explanation: Your immune system is a large network of organs, white blood cells, proteins (antibodies) and chemicals. This system works together to protect you from foreign invaders that cause infection, illness and disease.

Air goes past the epiglottis and into the trachea when you breathe in. from there, it goes to your vocal cords in the larynx until it reaches the bronchi. from the bronchi, air passes into each lung.