What is a fossil?
o a. an earlier form of an animal
o b. a different type of an atom
o c. the remains of a dead organism
o d. a code found in dna

How does the author's purpose in this passage differ from an author writing about her personal struggle living with asthma?

According to the cell theory, which describes cells? a. all organisms are composed of multiple cells. b. all cells have the same structure and function. c. cells are found in everything on earth. d. living organisms are not created spontaneously

Blood stem cells may develop into any kind of human blood cells. what kind of stem cells are blood stem cells? a. multipotent stem cells o b. totipotent stem cells o c. pluripotent stem cells o d. unipotent stem cells