Cell Fate

• What is differentiation? Different types of differentiation

Differentiation is the process by which embryonic stem cells differ from one another with distinct identities and functions. It involves the emergence of cell types. It achieves a stable terminal state and involves genes of gene expression to produce luxury proteins.

The earliest step in differentiation of the cell is cell determination where the cells become committed to a subset of cell fates.

Different types of differentiation?

• What is cell вЂ?fate’

Cell fate refers to the outcome of the cell (what the cell will become). Some cells are committed and their fate is determined.

• Understand how we know that DNA is not changed or lost during differentiation

We understand that by conducting experiment such as isolating the skin cells form a frog, extracting their nucleus and injecting it into an unfertilized egg whose nucleus has been destroyed. The egg develops to form a normal tadpole. In this experiment, it is clear that the differentiated donor did not lose any DNA.

• How do we know that cytoplasmic factors play a role in differentiation?

From experiments such as when they take a human (non-muscle) cell and fuse it with rate muscle cells. In this case this induces the human muscle gene activity.

Another experiment is when they fused a chicken red blood cell (inactive nucleus) with human cancer cells… this leads to reactivation of chicken genes.

This leads to the conclusion that the gene expression in cell that are differentiated is controlled by cytoplasmic