DNA Synthesis

Question 1

The nucleus during _____ phase is twice as large as it was during _____ phase because it now has twice as much DNA.

Answer 1

1. S

2. G (subscript 1)

Question 2

The parent cell doubles its DNA content through DNA synthesis by DNA replication in _____ phase.

Answer 2

S

Question 3

Whenever DNA is made, it is called DNA _____. When the newly made DNA is identical to the original DNA in the parent cell, it is called DNA _____.

Answer 3

1. synthesis

2. replication

Question 4

The complete _____ within any one cells is not present as one very long double strand (ds) of DNA.

Answer 4

genome

Question 5

There are _____ separate sets of dsDNA.

Answer 5

46

Question 6

dsDNA are only visible during the _____ of mitosis.

Answer 6

metaphase

Question 7

The 46 loosely coiled double _____ of DNA are not visible with a _____ microscope.

Answer 7

1. helices

2. standard

Question 8

DNA _____ begins when the individual sets of dsDNA separate by breaking the _____ bonds holding the two strands in the double _____ form.

Answer 8

1. replication
2. hydrogen
3. helix

Question 9

Once the DNA strands separate, _____ at each end of the strands read the sequence of the original strands and build two new strands that are _____ to the original strands.

Answer 9

1. enzymes

2. complementary

Question 10

DNA must be “read” in _____ direction to correctly place the new _____ during DNA synthesis, just like written languages must be read in _____ direction to make sense.

Answer 10

1. one
2. nucleotides
3. one

Question 11

DNA strands are read from the _____ prime end of the DNA to the _____ prime end (these numbers just refer to the specific _____ on the sugar molecule that connects with the _____ molecule).

Answer 11

1. 5
2. 3
3. carbon
4. phosphorus

Question 12

Because each of the two new sets of dsDNA contains one of the original strands, this type of DNA synthesis is known as the _____ _____ of DNA replication.

Answer 12

1. semiconservative

2. model

Question 13

To make the process of DNA replication efficient and rapid, within each set of separated DNA strands, DNA synthesis begins at _____ spots _____ on the strands.

Answer 13

1. multiple

2. simultaneously

Question 14

Name this enzyme for DNA replication:
Creates a “nick” in the supercoils of dsDNA, allowing them to loosen so that eventually the two strands can separate; this enzyme also repairs the nick (closes it) so that the dNA can resume its supercoiled helical shape.

Answer 14

DNA topoisomerase

Question 15

Name this enzyme for DNA replication:

Unwinds the double helix and initially separates the dsDNA.

Answer 15

DNA helicase

Question 16

Name this enzyme for DNA replication:

Helps keep the two single strands separated long enough for initiation of DNA replication.

Answer 16

Single-strand binding proteins (SSB proteins)

Question 17

Name this enzyme for DNA replication:

Connects or links the individual pieces of newly synthesized DNA during replication, forming a single strand.

Answer 17

DNA ligase

Question 18

Name this enzyme for DNA replication:

Responsible for initiating DNA synthesis in multiple sites down the single strand being copied.

Answer 18

Primase

Question 19

Name this enzyme for DNA replication:
DNA chain elongation, adding one nucleotide at a time to the new strand while it is being synthesized; editing or proofreading newly synthesized strand, comparing it to the original template strand; exonuclease action, recognizing a misplaced nucleotide, clipping it out, and replacing it with the correct one.

Answer 19

DNA polymerase (subtypes with different activities)