BIOL 1020 Lecture Notes - Lecture 29: Metaphase, Dna Replication, Dna Mismatch Repair

1. The DNA strand that is synthesized continuously is called thelagging strand.

2. The DNA strand that is synthesized discontinuously is called theleading strand.

3. DNA ligase joins adjacent Okazaki fragments together into acomplete strand.

4. DNA polymerases cannot initiate synthesis of a new DNA strand;they can only add bases to an existingstrand.

5. DNA polymerase I removes the RNA primer and synthesizes ashort sequence of DNA that will base pair with the parent strand ofDNA.

1. During DNA replication, proteins unwind the DNA duplex, and separate the DNA strands. Those proteins include:

a.) DNA polymerase and ligase

b.) Single-stranded DNA binding and protein primase

c.) Helicase and DNA polymerase

d.) Helicase and single-stranded DNA binding protein

2. What determines the nucleotide sequence of the newly synthesized strand during DNA replication?

a.) The particular DNA polymerase catalyzing the reaction

b.) The relative amounts of the four nucleotide triphosphates (ATP, GTP, CTP, and TTP) in the cell

c.) The nucleotide sequence of the template strand

d.) The primase used in the reaction

e.) Both A and D

3. The leading and the lagging strands differ in that

a.) The leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction.

b.) The leading strand is synthesized by adding nucleotides to the 3’ hydroxyl (OH) end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5’ phosphate (PO4) end.

c.) The leading strand is synthesized continuously, whereas the lagging strand is synthesized in short fragments that are ultimately stitched together.

d.) Both A and B

e.) Both A and C

Match the phrase its definition

DNA replication is semi-conservative

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions

DNA replication is bidirectional

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions

replication fork

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions

leading strand

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions

lagging strand

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions

DNA is antiparallel

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions

DNA is complementary

[ Choose ] place in which the two strands of DNA are being unwound and replicated the side of the DNA double helix that is synthesized continuously replication proceeds from the origin of replication in both directions simultaneously the side of the DNA helix that is synthesized using Okazaki fragments during DNA replication one strand is derived from the original DNA and the other strand is newly synthesized in the paired chains of the DNA helix adenine always binds thymine, and guanine always binds cytosine the two chains in the double helix are oriented in opposite directions