What is the function of the protein keratin? to provide support and structure for cells in hair, skin, and nails
to fight infections caused by bacteria and viruses
to increase chemical reaction rates in the digestive system
to transmit chemical signals throughout the body

to provide support and structure for cells in hair, skin, and nails

Explanation:

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 a. to provide support and structure for cells in hair, skin, and nails

Explanation:

Keratin - Wikipediaen.wikipedia.org › wiki › Keratin

Keratin (/ˈkɛrətɪn/) is one of a family of fibrous structural proteins known as scleroproteins. α-Keratin is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, calluses, and the outer layer of skin among vertebrates.

fossil's are like over rated rocks like low key not gonna lie i don't get why we can't just call them old rocks like for real i mean i call my grandpa and grandma that smh