Specialized Cells & Cellular Differentiation
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Cell Theory: Every cell comes from a previously existing cell but not all our cells are the exact
same.
We are made up of different kinds of cells, with unique functions and structures.
Human bodies need different kinds of cells to do things like fight infection, deliver oxygen,
digest food, and coordinate movement, these are called Specialized Cells.
Specialized cells they have physical and chemical differences that allow them to do their specific
job.
The process of cell specialization is called Cellular Differentiation.
Stem cells:
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Animals have stem cells, which can differentiate into many different kinds of cells through cell
division.
Differentiation occurs through cell division and which parts of DNA is turned on in each
daughter cell.
Refer to figure 1 on pg 77
There are two different types of stem cells, embryonic stem cells and tissue stem cells.
Embryonic stem cells can differentiate into any kind of cell.
Tissue stem cells can differentiate into only certain types of cell.
Blood from the umbilical cord contains lots of stem cells that can differentiate to any kind of
blood cell.
Regeneration:
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Regeneration refers to the process of tissues healing themselves.
o Ex. When you scrape or cut yourself and the skin grows back
Not all cells can do this. Nerve cells cannot regenerate and research is ongoing regarding the use
of stem cells as a solution to this problem.
Homework:
Read pg 58-60 #1-3
Read pg 77-79 #1,3,4,6