Cancer stem cells are not considered true stem cells because they are not derived from the three germ layers and do not have the same potential to differentiate into a wide range of cell types.

Embryonic stem cells are derived from embryos, while adult stem cells are derived from adult tissues. Embryonic stem cells are pluripotent, meaning they can differentiate into any cell type in the body, while adult stem cells are multipotent, meaning they can only differentiate into a limited number of cell types. Embryonic stem cells are also more difficult to obtain than adult stem cells.

Reprogramming is the process of converting adult cells into iPSCs by introducing specific genes or factors that reset the cells to an embryonic-like state.

Stem cell therapy has been successfully used to treat Parkinson's disease by transplanting dopamine-producing cells into the brain. However, stem cell therapy for Alzheimer's disease and Type 1 diabetes is still in the early stages of research.

The main ethical concerns associated with stem cell research include the destruction of embryos in the case of embryonic stem cell research, the potential for creating designer babies, and the risk of tumor formation from transplanted stem cells.

The United Kingdom was the first country to allow human embryonic stem cell research in 2001.

The main challenges in using stem cells for therapeutic purposes include rejection of transplanted stem cells by the recipient's immune system, difficulty in controlling the differentiation of stem cells into the desired cell types, and risk of tumor formation from transplanted stem cells.

Adult stem cells are most commonly used in clinical trials because they are easier to obtain and have a lower risk of causing tumors than embryonic stem cells.

Stem cell research has the potential to revolutionize regenerative medicine by repairing damaged tissues and organs, treating diseases such as Parkinson's and Alzheimer's, and developing new drugs and therapies.

The International Society for Stem Cell Research (ISSCR) is responsible for setting guidelines for stem cell research.

Transdifferentiation is the process of converting one type of cell into another, typically from one germ layer to another.

iPSCs have several advantages over embryonic stem cells, including being easier to obtain, having a lower risk of causing tumors, and being able to be tailored to specific patients.

Cancer is caused by a defect in the differentiation of stem cells, leading to the uncontrolled growth and division of cells.

The main challenges in using stem cells to treat genetic diseases include difficulty in delivering stem cells to the target tissue, risk of immune rejection, and difficulty in controlling the differentiation of stem cells.

Reversing aging is not a potential application of stem cell research, as stem cells cannot reverse the natural aging process.