Respuesta :
Mucus, saliva and tears are all part of the immune system, which helps fight off foreign and harmful cells. ... Another similarity is that mucus, saliva, and tears are all produced by exocrine glands.
Mucus, saliva and tears are all part of the immune system, which helps fight off foreign and harmful cells. ... Another similarity is that mucus, saliva, and tears are all produced by exocrine glands.