The skin and bodily secretions provide the first line of defense against infection. one response in this category that is common during upper respiratory virus infections is mucus production.
First line of defense is the physical and chemical barriers that protect the body from microbes. These are the tears, saliva, skin, cilia, etc. The primary role of first line of defense is the prevention of the microbes from entering inside the body.
Upper respiratory virus infections are those that infect the pathway from nostrils till the pharynx. Since their primary defense mechanism is to produce mucus, therefore in case of infections, mucus production increases to many folds than normal.
To know more about First line of defense, here
brainly.com/question/815290
#SPJ4
