Test #7: DNA, RNA, & DNA Technology

Franklin’s X-ray diffraction images suggested that the DNA molecule resembled a tightly coiled spring, a shape called a helix.

• True
• False

Chargaff observed that the amount of adenine in an organism always equaled the amount of thymine.

• True
• False

The strands of a DNA molecule are held together by hydrogen bonding between adenine with guanine molecules and cytosine with thymine molecules.

• True
• False

After replication, the nucleotide sequences in both DNA molecules are identical to each other and to the original DNA molecule.

• True
• False

Only DNA molecules contain the nitrogen base called uracil.

• True
• False

Despite years of research, the actual structure of the DNA molecule is still unknown.

• True
• False

Only ribosomal RNA plays a role in translation.

• True
• False

All of the following are true about the structure of DNA except

• short strands of DNA are contained in chromosomes inside the nucleus of a cell.
• every DNA nucleotide contains a sugar, a phosphate group, and a nitrogen base.
• DNA consists of two strands of nucleotides joined by hydrogen bonds.
• the long strands of nucleotides are twisted into a double helix.

Molecules of DNA are composed of long chains of

• amino acids.
• fatty acids.
• monosaccharides.
• nucleotides.

Which of the following is not part of a molecule of DNA?

• deoxyribose
• nitrogen base
• phosphate
• ribose