A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that embryos of dissimilar organisms, such as sharks and humans, resemble each other. Embryology involves the study of the formation and the development of an embryo and the fetus. It is one type of evidence of evolution such that the embryos of many different kinds of animals, mammals, reptiles, birds, fish among others, are similar showing a common ancestry.
Either C or D. I think C, but I'm not too sure...
Ok mauguguv is there a lot more and more than a few minutes later I can have
Answer:
Totipotent Stem Cells - They can differentiate into any type of human body cell or the placenta.
Example: Fertilized egg cells.
Pluripotent Stem Cells are from totipotent cells and can differentiate into any cell in the human body; however, not many are in the placenta.
Example: Blastocyst cells.
Multipotent Stem Cells - They can only differentiate into closely related cells.
Example: Blood stem cell
Unipotent Stem Cells - They can only produce their type of cell.
Example: Skin stem cells (which can only become a new skin stem cell).
Explanation:
