bio quiz 8.1-5

Which result 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 lived.
• Mice injected with dead S bacteria lived.
• Mice injected with dead S and live R bacteria died.

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

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

After examining the DNA of different organisms, which of the following did Erwin Chargaff conclude about the four bases?

• A = T and C = G
• A=C=G=T
• A = C and G = T
• A+T=C+G

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

• GTTACGC
• UCCGTAT
• TGGCATA
• CAATGCG

What holds base pairs together?

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

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.

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

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.

When new DNA molecules are formed, almost all errors are detected and fixed by

• the correct nucleotide.
• the sugar-phosphate backbone.
• DNA polymerase.
• one DNA strand.