bio quiz 8.1-5

Which result of Frederick Griffith’s experiments led him to believe in a “transforming principle”?

• a) Mice injected with live S bacteria died.
• b) Mice injected with live R bacteria lived.
• c) Mice injected with dead S bacteria lived.
• d) Mice injected with dead S and live R bacteria died.

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

• a) hydrogen bonds.
• b) nitrogen-containing bases.
• c) phosphate groups.
• d) ring-shaped sugars.

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

• a) A = T and C = G
• b) A=C=G=T
• c) A = C and G = T
• d) A+T=C+G

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

• a) GTTACGC
• b) UCCGTAT
• c) TGGCATA
• d) CAATGCG

What holds base pairs together?

• a) hydrogen bonds
• b) sugar-phosphate backbones
• c) pairs of double-ringed nucleotides
• d) 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)

• a) nucleotide.
• b) X in a circle.
• c) double helix.
• d) covalent bond.

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

• a) conservation.
• b) preservation.
• c) replication.
• d) synthesis.

What are the main functions of DNA polymerase?

• a) breaks hydrogen bonds and exposes bases
• b) holds DNA strands apart and attracts bases
• c) zips and unzips the double-stranded DNA
• d) 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

• a) two completely identical strands of DNA.
• b) one original and one new strand of DNA.
• c) one strand of DNA and one strand of RNA.
• d) two strands that mix original and new DNA.

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

• a) the correct nucleotide.
• b) the sugar-phosphate backbone.
• c) DNA polymerase.
• d) one DNA strand.