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Two individuals are represented in each of the choices A–D in the figures below; individual 1 is one of the parents of individual 2. The asterisk seen in each choice indicates the occurrence of a single mutation during a particular cell division event. Which one of the choices will lead to a mutation in every cell of the individual in which the mutation occurred?  

As a new DNA strand is being synthesized, DNA synthesis proceeds:

RNA polymerases can start an RNA chain without a primer.

Which of the following scenarios could cause a whole genome duplication event that leads to the production of a new species?

Nucleosomes are fundamental structural units of chromatin in eukaryotic cells. Which of the following statements accurately describes the structure and role of nucleosomes?

Which of the following libraries would be expected to be essentially the same?

The segment of mRNA below includes the region that codes for the binding site for the initiator tRNA that is needed in translation. 5′-GUUUCCCGUAUACAUGCGUGCCGGGUAGCCC-3′ Use the genetic code table to translate the sequence into a polypeptide sequence. Write your answer using the single letter abbreviations for the amino acids.  

Most cancers arise from cells that have accumulated multiple mutations.

You have a piece of DNA that includes the following sequence: 5′-ATAGGCATTCGATCCGGATAGCAT-3′ 3′-TATCCGTAAGCTAGGCCTATCGTA-5′ Which of the following RNA molecules could be transcribed from this piece of DNA?

In mammals, females have two X chromosomes and males have a single X chromosome in addition to a Y chromosome. Thus, females have a ‘double dose’ of all the genes on the X chromosome. Females address this imbalance by inactivating one of the two X chromosomes in every cell. How do the cells do this?