10.4 Cell Differentiation

Differentiation – cells become different; form into many types of cells Differentiation – cells become different; form into many types of cells Become specialized for certain tasks Become specialized for certain tasks

Stem Cells = Unspecialized cells from which other cells develop = Unspecialized cells from which other cells develop Totipotent – can develop into any kind of cell in body (ex. First fertilized cells) Totipotent – can develop into any kind of cell in body (ex. First fertilized cells) Blastocyst – hollow ball of cells; early embryo Blastocyst – hollow ball of cells; early embryo Pluripotent – inside blastocyst; can develop into most types of cells (not the tissue around embryo) Pluripotent – inside blastocyst; can develop into most types of cells (not the tissue around embryo)

Types Embryonic stem cells – research shows can form into any cell type in human body Embryonic stem cells – research shows can form into any cell type in human body Adult stem cells – “pools” to replenish damaged/dead cells Adult stem cells – “pools” to replenish damaged/dead cells * Are multipotent  typically develop into cells from the type of tissue they originated * Are multipotent  typically develop into cells from the type of tissue they originated * Ex. Bone marrow transplants = stem cell transplants for blood * Ex. Bone marrow transplants = stem cell transplants for blood

Adult cells altered to have properties of embryonic stem cells = induced pluripotent stem cells; still unknown effects in humans Adult cells altered to have properties of embryonic stem cells = induced pluripotent stem cells; still unknown effects in humans Amniotic fluid stem cells – need more research Amniotic fluid stem cells – need more research

Stem Cell Research Benefits – replace injured cells/tissues Benefits – replace injured cells/tissues Ex. Heart cells, brain cells, nerve cells Ex. Heart cells, brain cells, nerve cells Ethics – Ethics – * Adult stem cells – fine * Adult stem cells – fine * Embryonic stem cells – destroys embryo * Embryonic stem cells – destroys embryo