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How many different kind of cells are in the human body?
Answer 1:

I had to look that one up. It looks like there are about 200 kinds. I bet that there are different variations on those 200 kinds too. Here are some of the general kinds of cells:
Cells that make stuff for use outside the cell, such as mucus, saliva, digestive enzymes, connective tissue, and hormones.
Cells that protect other cells, like the cells on the outside of our skin.
Cells for absorbing things, like the ones in our digestive system, lungs, and urinary system.
Cells for storing and processing energy, such as fat cells, liver cells, and muscle cells.
Nerve cells that sense information (HOT!), tell our bodies what to do (Pull back hand!), and allow us to think, plan, feel, and coordinate (I’m not touching the hot plate again!).
Cells for reproducing—eggs and sperm
Cells that contract—muscle cells
Cells that help other cells do their jobs
Cells that attach germs and other invaders
Cells that make and destroy bone
Cells that process chemicals—like in our liver and kidneys
Cells that carry oxygen—red blood cells.

All of these cells have their own shapes and sets of organelles that help them do their jobs. Every cell type has the same set of DNA, they just use different parts of it. The only exceptions are the mature red blood cells (which lose their nuclei) and the sex cells, which only have half the genetic material of the other cells. Can you figure out why?

You may be interested in studying cell biology.

Thanks for asking,

Answer 2:

There are about 200 different kinds of cells in the human body. The number is “about 200” because our understanding of the biology of the human body is not complete enough to claim we’ve discovered every type of cell. Also, the process of putting cells in different categories is complex and it requires making decisions that may not be entirely straightforward.

In a sense, there are opinions involved because someone can consider two cells to be the same type while someone else thinks they’re different. But the scientific community has decided on certain types of cells because it’s important for scientists to be able to communicate about which cell they’re studying.

An interesting thing about the many different types of cells is that they all come from 1 cell, a sperm fused with an egg. All cells that come from that cell are genetically identical. Therefore, the different types of cells don’t have different DNA, they just read different parts of the DNA. If you think of the DNA as an encyclopedia, nobody reads an entire encyclopedia, they just read the parts that are important to them.



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