8.3 DNA Replication

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

What are the main functions of helicase?

• breaks hydrogen bonds and exposes bases

• holds DNA strands apart and attracts bases

• forms hydrogen bonds to make double-stranded DNA

• binds nucleotides and corrects base pair errors

What are the main functions of single stranded binding proteins?

• breaks hydrogen bonds and exposes bases

• holds DNA strands apart

• forms hydrogen bonds to make double-stranded DNA

• binds nucleotides and corrects base pair errors

Which of the following events occurs directly after a DNA molecule 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

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.

Figure 8.1 shows a single strand of DNA. Choose the first three nucleotides of the other DNA strand.

• GGT

• CCT

• GGC

• TTA

In humans, where does DNA replication take place?

• cytoplasm

• ribosome

• nucleus

• vacuole

When does replication occur?

• during the cell’s S phase

• when nucleotides float in the nucleus

• during the cell’s M phase

• when tRNA unzips DNA