How do mutations increase the genetic variation within a species?

Mutations increase genetic variation because if everyone has a mutation the wiill all be different
example Mom has blue eyes dad has brown eyes the genetic varieation with the child is brown eyes because its dominent everyone is different because of mutations+genetic variation
It also has to do with DNA coding for different protteins to give you different genes DNA

the glands which are associated with each description is given below:

pancreas - is an endocrine and exocrine gland that secretes juices with enzymes for digestion. salivary glands- with protection and digestion in the mouth. liver- secretes bile for digestion.   lachrymal glands - secrete tears to moisten eyes and protect them from particles and infection.   sweat gland -regulates water, salt, and temperature. oil glands - to form a protective barrier on the skin.   goblet cells - secrete mucus for protection.