Human Hair
Sub Topics
Human Hair
Variations in Human Hair
Hair Structure
Hair Strength
Hair Dimensions
The Hair Growth Cycle
Hair Patterns
The Physical Properties of Hair
Hair Types
Dry or Greasy Hair?
Hair Color
The hair we have
All land mammals - including humans - have hairy skins, although in us most of the hair is not immediately visible. As with other mammals, our hair characteristics are inherited directly from our parents. Your hair color and hair type were decided for you, as were the colors of your eyes and your skin.
Cat's hair insulates their bodies and may also help them to identify each other
In the end, whether or not your hair has the precious quality of being 'easy to manage' depends on what your parents have passed on to you from your ancestors.
The human 'kitten' has more hair per square centimeter of her skin than the real one, only most of it is too fine to see.
What hair does
Scientists believe that hair has evolved for the identification of individuals, and for sexual or status display to other members of their species.
Hairs are important sense organs, particularly those on the eyelids and eyebrows, since they are involved in the sensation of touch. It has also been suggested that hairs carry an individual's scent, by which he or she may be recognised and which may attract possible mates. Human hair almost certainly fulfils the same display functions as that of other animals.
Humans have much less visible hair than do other primates like apes and monkeys. Surprisingly, however, a square centimetre of human skin carries a greater number of hair-producing sites (called follicles) than the same area of the skin of other primates. We have lost the requirement for insulating our bodies, and presumably the hair which animals need for this.
Managing our hair
The appearance of the hair is the one feature of the body over which humans, unlike other primates, can have direct control. You can change the length, shape, color and style of your hair (including, for men, facial hair) according to the age you wish to appear, and the economic and social status you want to claim.
The style, length and condition of hair all play a part in how we perceive the people we meet.
HAIR FACTS
Hair Distribution
Humans are covered all over in hair, except on the palms of the hands, the soles of the feet, and the lips.
Hair is most obvious on the head and face (including the nose and ears in some people), the armpits, the groin, and (in men) the chest and legs.
How much hair do we have?
On average, each person's head carries about 100,000 hair follicles. Some people have as many as 150,000.
On a baby's head, there are about 1,100 follicles per square centimetre.
By the age of 25, this number has fallen to about 600, but the number depends on the physical type of the individual.
Between the ages of 30 and 50, the number drops further, to 250-300. There is only a slight further fall with age.
Each follicle grows about 20 new hairs in a lifetime. Each new hair grows for several years, and can reach over a metre in length.
Each hair falls out eventually, and is replaced by a new one.
Red-heads have fewer than the average number of follicles per square centimetre of their scalp
BY
MILAN
PGDM
IIIRD
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