One species’ DNA differs from others in its______ . a. nucleotides c. double helix b. DNA sequence d. sugar–phosphate backbone

In a DNA molecule, a sugar, phosphate, and nitrogenous base are collectivley referred to as   A. DNA   B. RNA   C. a nucleotide   D. a codon

Which of the following nucleic acids is a component of ribosomes?   a.DNA   b.Transfer RNA   c.Ribosomal RNA   d.Messenger RNA

Explain why scientists preferred proteins as the source of genetic material over DNA.   A. DNA seemed too simple of a molecule compared to proteins   B. Proteins are made up of combinations of 20 different amino acids compared to DNA's 4 bases. The larger number seemed more likely to account for all the variety and diversity in organisms.   C. Scientists knew more about proteins than they did DNA.   D. All of the answers are correct explanations.

Which of the following is true about DNA? a. DNA consists of two strands of nucleotides held together by weak hydrogen bonds. b. DNA has a globular shape. c. DNA contains the sugar, ribose. d. DNA contains the encoded information for building phospholipids.

A fragment of DNA has the sequence 5'-ATCCGCT-3'. Following DNA replication, the complementary strand is 3'-TAAGCGA-5'. What type of mutation occurred? a. Frameshift b. Transversion c. Pyrimidine dimer d. Transition