General Examples:
* Hair and Nails: These are made of a protein called keratin, produced by living cells, but the final structure is mostly made of dead cells.
* Skin: The outer layer of skin, the epidermis, is composed of dead cells that constantly shed and are replaced by new ones.
* Wood: The majority of the wood in a tree is made up of dead cells that provide structural support.
* Bones: While bones contain living cells, the hard, outer layer is mostly made up of dead cells, specifically osteocytes.
Specific to Animals:
* Feathers: The structure of feathers is made from keratin, produced by living cells, but the final product is mostly dead.
* Scales: Scales, like those found on reptiles and fish, are formed from dead cells.
* Teeth: The enamel covering our teeth is mostly made up of dead cells.
Specific to Plants:
* Bark: The outer layer of bark in trees is mostly dead cells.
* Xylem: The tissue that carries water in plants is made up of dead cells, specifically xylem vessels.
It's important to remember that even though these things are made of dead cells, they were formed by living cells and serve important functions within the organism.
