Key Difference: The adult stem cells are derived from adult tissue, and have the ability to regenerate into all the cell types of the organ from which they originate. Embryonic Stem Cells, on the other hand, are stem cells that are derived from the inner cell mass of a blastocyst. Blastocyst is an early-stage of the embryo that it reaches approximately 4-5 days after fertilization.

 A stem cell is a reserve cell that each creature has in its body. The stem cell has the ability to grow into any cell that is required by the body and to multiply, so that it can replace any and all dead or damaged adult cells.

Many systems in our body have a supply of stem cells that helps it to heal and replace any dead or damage parts. Some of these parts include the skin system, liver system, etc., which is why it is easier for the body to heal these parts, as it can just replace the damaged parts. However, there are other systems in our body, such as the heart, spinal cord, brain and pancreas, which so not have a supply of stem cells. Researchers are currently working to develop stem cells that may help us to heal and/or replace these parts.

Stem Cells are greatly beneficial as they have the ability to divide or self-renew indefinitely. There are four main types of stem cells as categorized by the researchers working with them. These are adult stem cells, fetal stem cells, embryonic stem cells, and more recently, induced stem cells.

Adult Stem Cells are undifferentiated cells, which means that they have not become specialized stem cells with a particular function. These cells have the ability to divide or self-renew indefinitely. They also have to ability to generate all the cell types of the organ from which they originate.

The adult stem cells are derived from adult tissue, and depending on the tissues they are derived from, they have the ability to regenerate into all the cell types of the organ from which they originate.

Embryonic Stem Cells, on the other hand, are stem cells that are derived from the inner cell mass of a blastocyst. Blastocyst is an early-stage of the embryo that it reaches approximately 4-5 days after fertilization. At this stage, the embryo has consist of 50–150 cells. Here the embryos are generated by IVF (in vitro fertility) clinics, so that the researchers can study the stem cells and their implications.

The Embryonic Stem Cells are also known as pluripotent stem cells as they have the ability to differentiate into any cell type, which means that they have a possibility of infinite applications within the human body. Like the adult stem cells, they also have the ability to regenerate indefinitely, as practically, they entire human body grows from single embryo.

However, embryonic stem cell research has been subject to much controversy, due to the fact the stem cells are taken from an embryo. Many claim that this is inhumane, and that embryos are life and should have the same rights. Many people also look down upon and criticize the fact that these embryos are generated by IVF, which some consider to be against nature.

Comparison between Adult and Embryonic Stem Cells:

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