The oldest type of bacteria is over 3 million years old I think. It comes from the cyanobacteria family! The bacteria is a type of algae! Discovered by Gregorio V. in the Late 1900's.
Hairs are mostly fibrous proteins and are composed of keratin, and also the main constituent of skin, nails, wool, woof, feathers etc.
Keratin is the essential fibrous protein which has a structural and protective functions in the epithelium.
The network of glands that release chemical messengers directly into the bloodstream is called the endocrine system. The endocrine system produces and secretes t<span>hese chemical messengers, referred as </span>hormones directly into bloodstream to transmit signals to appropriate part of body. The hormones regulate bodily functions like growth, metabolism, <span>tissue function, sexual function, reproduction, </span>sleep and mood.
The major purpose(s) of mitosis is for growth and to replace worn out cells.
