Antony van Leeuwenhoek
Antony van Leeuwenhoek (1632 - 1723) was a Dutch tradesman who sold
fabrics. In his leisure time, he liked making and using microscopes.
(Although microscopes had been invented about 50 years before Leeuwenhoek
was born, people at that time treated microscopes more like a toy
than a useful scientific tool.)
Leeuwenhoek first studied the fibres of the fabrics with his microscopes.
Then he started studying flowers, leaves, insects, blood, hair,
skin, etc. He was the first person to describe blood cells and to
see the blood flow in capillaries.
You may discover lots of interesting things with a microscope,
just like Leeuwenhoek
Types of human
cells
There are many different types of cells in a human body. These cells
have different shapes, sizes, functions and life spans. For example:
1. Sperm have a tail so that they can swim towards the egg for
fertilization.
Sperm
2. Nerve cells have a long process called axon, along which messages
are carried away.
Nerve cell
3. The life span of white blood cells (such as phagocytes
and lymphocytes) is only a few days, but red blood cells have
a life span of about 120 days.
White blood cells
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