The statement "stem cells are only found in embryos, not in adult humans" is false. Stem cells are indeed found in both embryos and adult humans, but they differ in type and potency. Embryonic stem cells are pluripotent, meaning they can develop into any cell type in the body and are found only at very early stages of embryonic development (e.g., blastocyst stage). In contrast, adult stem cells, also called somatic stem cells, exist in many tissues throughout the body after development. Adult stem cells are usually multipotent, meaning they can give rise to a limited range of cell types within their tissue of origin. These adult stem cells are involved in maintaining and repairing tissues throughout life, such as in bone marrow, skin, brain, liver, and more. They play a key role in tissue homeostasis and regeneration and have been used in medical treatments such as bone marrow transplants. Therefore, stem cells are not exclusive to embryos; they are also present in adult humans with important regenerative functions.