6.8 stem cells

What is a stem cell?

A stem cell is an undifferentiated cell, capable of becoming any other type of cell.

What are the two main features of stems cells?

1. They can divide by mitosis to form more cells

2. They can differentiate into different types of specialised cell

Name four types of stem cell. 

1. Totipotent stem cells 

2. Pluripotent stem cells

3. Multipotent stem cells

4. Unipotent stem cells

What is the difference between totipotent and pluripotent stem cells?

Totipotent stem cells can differentiate into any cell typeand produce whole organisms, while pluripotent stem cells can only differentiate into most cell types and cannot form whole organisms. 

What are multipotent stem cells?

Multipotent stem cells can only differentiate into a few different cell types. 

What do we call the plant tissues that are continually growing and contain stem cells?

Plant tissues that are continually growing and contain stem cells are called meristem tissues.

Meristem tissues are found in the tips of the roots and shoots.

Which types of stem cell are found in embryos? 

Totipotent stem cells are found in the early stages of embryos and pluripotent stem cells are found after the first week. 

Which types of stem cells are found in adults?

Adult tissues may contain multipotent and/or unipotentstem cells. 

How can stem cells be used to treat Alzheimer's disease and Parkinson's disease?

Transplanted stem cells can help to regenerate nerve cells in the brain. 

Give four uses of stem cells in research and medicine. 

1. Treatment for certain diseases 

2. Testing new drugs 

3. Studying development of organisms 

4. Identifying causes of disorders