Download 4-4 Cell Differentiation I. Differentiation 1. Differentiation

4-4 Cell Differentiation
I.
Differentiation
1. Differentiation- is the process by which cells change in structure
and become capable of carrying out specialized functions.
2. As cells differentiate, they become different from one another.
They also form groups made of other, similarly specialized cells.
These groups then form tissues and organs.
A. Difference in Structure
1. Through mitosis and differentiation, the single cell becomes an
organism with specialized structures.
B. Difference in Function
1. As cells differentiate in structure, they begin to carry out different
functions.
a. Leaf cells have chloroplasts while root cells do not.
C. Tissues, Organs, and Systems
1. When cells differentiate they also become organized.
a. For example muscle cells in animals become organized into
long strands of muscle tissue that can move legs and arms.
D. Increasingly Specialized Cells
1. As development continues, more fine-grained differentiation
occurs.
a. For example the cells in your retina differentiated early in your
development
1. Rod cells cannot see color and Cone cells can detect
color.
II. How Cells Differentiate
1. Once a cell’s future has been determined, when and how much it
changes depends on is DNA, its function, and the type of
organisms.
A. Cell Differentiation Among Animals
1. Many adult animals, such as insects and some crustaceans and
reptiles can grow a limb or tail to replace a lost one. Cells at the
point of injury can differentiate.
2. This does not occur in humans. Once the human cell
differentiates, they lose the ability to become other types of cells.
3. Humans do produce certain cells called stem cells that can
differentiate throughout life. These cells become specialized for
other cells that the body needs like red blood cells, white blood
cells and platelets.
B. Cell differentiation in Plants
1. In plants differentiated cells become grouped into the tissues that
make up the roots, stems and leaves.