Growing, growing … gone?
Humans have hair all over our bodies, except on the palms of our hands, soles of our feet, lips and eyelids.
Hair growth takes place below the surface of the skin, in the epidermis. Inside our hair follicles are cells that divide and multiply.
When there are lots of new cells, the inside of the follicle becomes full and older cells get pushed out. These older cells harden as they exit the follicle and form the hair shaft, which is made up of dead tissue and a protein called keratin.
The hair shaft becomes longer and longer as more and more cells divide and multiply. This is known as the active phase of hair growth. Depending on the type of hair, this phase can go on for months or even years. After the active phase comes the resting phase, after which the hair falls out. Don’t worry though – it’s just making room for a new one to grow.
Why do we have hair?
It’s not just for tying up in pretty ponytails! Hair is very important because it helps to regulate our body temperature, cooling us down in summer by allowing sweat to evaporate quickly, and keeping us warm in winter.
DID YOU KNOW?
There are about five million individual hairs on the human body!
How do they grow?
Nails are formed when epidermal cells below the nail root move up to the surface of the skin. As they increase in number, the cells closest to the nail root become flattened and press tightly together. These fuse to form a thin plate and all these plates pile up in layers to form the nail.
Why do we have nails?
Your nails are there to protect the sensitive tips of your fingers and toes. Plus they help us scratch those annoying itches!
DID YOU KNOW?
Fingernails grow three to four times quicker than toenails.