1. Cell Differentiation
Section 10.4

2. From one cell to many Each of us started life as one cell
Living things pass through a developmental stage called an embryo
During the develop process cells become more and more differentiated and specialized for particular functions
Differentiation = the process in which cells become specialized
Specialized to perform certain tasks

3. Mapping Differentiation
The process of differentiation determines the cells ultimate identify
Will it be a nerve cell or a muscle cell
Scientist have been able to map out each and every cell division on a microscopic worm C. elegans

4. Stem cells and development
Totipotent = cells that are able to do everything, to develop into any type of cell in the body
Human Development
After 4 days of development the embryo forms a blastocyst
Blastocyst = A hollow ball of cells with a cluster of cells inside known as the inner cell mass
Cells have already begun to specialize
Outer cells – attach embryo to its mother
Inner cells – cells that become the embryo
Pluripotent = cell that can develop into most of the body’s cell types

5. Stem cells Unspecialized cells which differentiated cells develop
2 types of stem cells
1. Embryonic stem cells – found in early embryos
2. Adult stem cells – limited life span and need to be constantly replaced
Example: skin or blood
Multipotent = adult stem cells that can develop into many types of differentiated cells
Example: blood cells