2. Cells and Control: Stem Cells

Question 1

What are Stem Cells?

Answer 1

Differentiate into different types of cells to become specialised

Undifferentiated cells are called stem cells

Depending on instructions - stem cells can divide by mitosis - become new cells which then differentiate

Found in early human embryos - have the potential to divide and produce any kind of cell - all different type of cell found in humans come from the few cells in the early embryo

Really important for growth and development of organisms

Adults have stem cells - in bone marrow - aren’t as versatile as embryonic stem cells as can’t produce any cell type

In animals adult stem cells used to replace damaged cells e.g. new skin or blood cells

Question 2

In plants, what tissue contains Plant Stem Cells?

Answer 2

Meristem contain plant stem cells

In plants - only cells that divide by mitosis found in plant tissues called meristems

Meristem tissue - found in areas of plants that are growing e.g. tips of the rots and shoots

Meristem produce unspecialised cells that can divide and form any cell type in plant - act like embryonic stem cells - unlike human stem cells they can divide and differentiate - generate any type of cell for as long as the plant lives

Unspecialised cells form specialised tissues like xylem and phloem

Question 3

How can stem cells be used in medicine?

Answer 3

Doctors use adult stem cells to cure diseases e.g. sickle cell anaemia - can be cured with a bone marrow transplant