gene expression

Totipotent

Cells that can divide and differentiate into all types of body cells and extra-embryonic tissues.

Cell specialisation

The process by which cells become specialised for a specific function due to selective gene expression.

Why do totipotent cells exist for short amount of time in embryo

Because cells begin to specialise as development progresses, so they lose the ability to become all cell types.

Give one example of a unipotent cell and what it produces

Muscle stem cells → produce cardiomyocytes (heart muscle cells).

State one advantage of using pluripotent stem cells in medicine.

They can differentiate into many different cell types, useful for treating diseases.

Stem cells

A cell that can divide and differentiate into specialised cell types.

Pluripotent stem cell

Able to form many different cell types but not extra-embryonic tissues.

Multipotent stem cells

Able to form a limited range of related cell types

Unipotent stem cell

Able to form only one type of cell

Embryonic stem cells

Stem cells found in embryos that are pluripotent

Adult stem cells

Stem cells found in mature organisms that are multipotent or unipotent.

Gene expression

The process by which information from a gene is used to produce proteins.

What is a transcription factor

A protein that controls which genes are turned on or off

What is an induced pluripotent stem cell (iPS cell)?

An adult cell that has been reprogrammed to become pluripotent.

What is cell specialisation controlled by?

Selective gene expression