Đơn vị đo độ dài phân tử DNA? Angstrom

Do you think the gene eef1 alpha1 supports cell theory? explain your response.

How does the carbon cycle involve an exchange of carbon

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.