Question: Humans, pets, and petunias all pass through an early stage of development called a(n) ___________.

Answer: embryo

Question: Cells become _____ through the process of differentiation

Answer: specialized

Question: Scientists have mapped the outcome of every ___ that leads to differentiation in the development of the microscopic worm C. elegans.

Answer: cell division

Question: Most cells in the adult body are no longer capable of___.

Answer: Differentiation

Question: Which is an example of a totipotent cell?

Answer: fertilized egg

Question: Cells that are pluripotent are unable to develop into the tissue that

Answer: surrounds an embryo

Question: Adult stem cells are best described as

Answer: multipotent

Question: Complete the concept map by identifying some of the types of cells that embryonic cells give rise to. Then explain how stem cells are like the stem of a plant.

Answer: Many different types of cells can come from stem cells, like the branches emerging from a stem.

Question: Which is not a new, potential benefit of stem cell research?

Answer: growing new skin cells to repair a cut

Question: What is the main reason that embryonic stem cell research is considered ethically controversial?

Answer: embryos are destroyed in the process