DNA, RNA, and Proteins

Which of Frederick Griffith's experiments led him to believe in a transforming principle?

• mice injected with live S bacteria died
• mice injected with live R bacteria died
• mice injected with dead S bacteria lived
• mice injected with dead S and live R bacteria died

As a result of Hershey and Chase experiments, scientists believe that

• radioactive isotopes can be used safely
• viruses use bacterial DNA to reproduce
• the transforming principle is DNA
• bacteriophages can be grown in culture medium

The four types of nucleotides that make up DNA are named for their

• hydrogen bonds
• nitrogen-containing bases
• phosphate groups
• ring-shaped sugars

Which type of the following DNA sequences is complementary to the base sequence ACCGTAT

• GTTACGC
• UCCGTAT
• TGGCATA
• CAATGCG

Combining the work of other scientists with their own research, Watson and Crick discovered that two strands of DNA join together to form a(n)

• nucleotide
• X in a circle
• double helix
• covalent bond

What holds base pairs together?

• hydrogen bonds
• sugar-phosphate backbones
• pairs of double-ringed nucleotides
• nitrogen-carbon bonds

The process that makes an exact copy of a cell's DNA is called

• conservation
• preservation
• replication
• synthesis

What are the main functions of DNA polymerase?

• breaks hydrogen bonds and exposes bases
• holds DNA strands apart and attracts bases
• zips and unzips the double-stranded DNA
• binds nucleotides and corrects base pair errors

Which of the following events occurs directly after a DNA molecules is unzipped?

• Mismatched nucleotide bases are identified and replaced
• Free-floating nucleotides pair up with exposed bases
• Identical double-stranded DNA molecules are formed
• Enzymes break hydrogen bonds between base pairs

The process of making new DNA molecules is semiconservative. This means that every new DNA molecule is composed of

• two completely identical strands of DNA
• one original and one new strand of DNA
• one strand of DNA and one strand of RNA
• two strands that mix original and new DNA