iSCIENCE
HAIR-
RAISING!
To look at our FUSE ‘Summ-hair’ 2016 theme
in ‘fur’-ther detail.......here is a
‘bunch’ of human hair-related info for you.
Each amazing human body is
covered in about 5 million hairs!
This diagram shows how it is
only the part called the hair
shaft that we see poking out
of our skin. The 'living' part of
the hair lies beneath the skin's
surface inside a tiny organ
called the hair follicle. Each
hair's journey begins in the
bulb at the bottom of the hair
root and is nourished by blood
vessels through the hair's
fixing point at the papilla.
As each hair edges to the
skin's surface, the tough
protein called keratin is
deposited into its cells.
Sebaceous glands feed and
waterproof every strand with
healthy oils ready for life on
the outside!
And...does that really say
"muscle"? Surprisingly, yes!
When you get cold, tiny hair
erector muscles react and
shorten ('contract'). This pulls
the hair follicle and makes
the hair shaft stand on end.
You might see 'goose bumps'
where the skin bunches up
around the hairs. This whole
chain-reaction traps bodytemperature air close to our
skin and helps keep us warm.
Scalp Science
££ There are around 100,000 hairs
on a healthy head ('scalp') of
black or brown hair.
££ Redheads generally have more
like 90,000 strands of hair.
££ Blondes have thinner strands
although up to 140,000 of them.
££ Human hair grows by about 1.25
cm per month; 15 cm per year.
££ For most people, the longest
a single hair will grow is (in
distance) 1 metre...or (in time)
1 to 6 years!
££ Each hair is at its own stage in
the growth cycle.
££ 50-100 hairs fall out every day.
CHECK OUT:
• iMATHS: MATHS AT WORK
• iTECH: HAIRY MATERIALS!
• iWORLD: THE AFRO
4
FUSE