What do saliva, tears, and nasal mucus have in common? a .all can be classified as biological barriers. b .all contain langerhans cells. c .all can destroy bacterial cell walls. d. all are part of the complement system.

All can destroy bacterial cell walls.

C. All can destroy bacterial cell wall.

Saliva, tears and nasal mucus are physical and chemical barriers which are produced by the body as a defense against pathogens like bacteria and viruses. Saliva, tears and nasal mucus all these biological fluids which are secreted by mouth, eyes and nose. They release enzymes that breaks down the cell walls of bacteria and prevent their action on the body.

he is very short, and he can only reach halfway up on the elevator buttons. but on a rainy day, he has his umbrella with him, and he uses it to poke the button at the top.

sulfur dioxide

explanation: acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. these substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.