DNA as the Genetic Material

Question 1

The 2 helical strands of DNA run parallel to each other, but go in opposite directions.

Answer 1

Antiparallel

Question 2

Nitrogen base + the sugar =
without the phosphate group

Answer 2

Nucleosides

Question 3

Nitrogenous base, sugar, and 1-3 phosphates =

Answer 3

Nucleotides

Question 4

An array of nucleotides.

Answer 4

DNA

Question 5

RNA base pairs:

Answer 5

A + U
C + G

Question 6

DNA base pairs:

Answer 6

A + T
C + G

Question 7

Process of copying DNA for proper cell division to occur.

Answer 7

Replication

Question 8

Part of cell cycle.
Cell grows, carries out cell processes, and replicates its DNA.

Answer 8

Interphase

Question 9

Part of cell cycle.
Cell undergoes cell division.

Answer 9

Mitosis

Question 10

How DNA is copied to make DNA for new cells.

Answer 10

Replication

Question 11

Enzyme that separates the DNA strands into a lagging strand and a leading strand.
Unzips the double helix.

Answer 11

Helicase

Question 12

Easily replicated because it runs in the same direction as the original strand.
Replicated continuously.

Answer 12

Leading Strand

Question 13

Important enzymes in DNA replication:

Answer 13

Helicase
DNA Polymerase
Primase
Ligase
Topoisomerase

Question 14

Process of replication is described this way because each DNA molecule is made up of 1 old conserved strand of DNA and 1 newly synthesized strand.

Answer 14

Semi-Conservative

Question 15

Adds the appropriate base pairs.

Answer 15

DNA Polymerase

Question 16

Opposite in direction.
DNA polymerase can’t replicate as easily.

Answer 16

Lagging Strand

Question 17

On the lagging strand.
RNA primer attaches and the DNA polymerase adds small groups of base pairs.
What are these small groups of base pairs called?

Answer 17

Okazaki Fragments

Question 18

DNA sequence with altered nucleotides.
Can change the function of the DNA sequence or even render it unstable.

Answer 18

Mutation

Question 19

The parent DNA separates and a newly synthesized strand is added to each parent strand.
Each double helix of DNA created by replication contains 1 DNA strand from the parent and 1 newly synthesized DNA strand.

Answer 19

Semi-Conservative Replication

Question 20

Main steps in DNA replication:

Answer 20

Initiation
Elongation
Termination

Question 21

Runs 5’ to 3’.

Answer 21

Leading Strand

Question 22

Runs 3’ to 5’.
Antiparallel strand. Complementary to the leading strand.

Answer 22

Lagging Strand

Question 23

Helicase (enzyme) break down the hydrogen bonds between base pairs (“unzips”). —> 2 strands of DNA must be separated to use the DNA as a template for replication. —> DNA replication fork.
Topoisomerase (enzyme) surround the “unzipped” separated strands of DNA and relax the twisting of helices.
Parent DNA is separated into 2 strands: leading strand and lagging strand.
Primase (enzyme) builds short stretches of RNA called primers that are required to start elongation.

Answer 23

Initiation

Question 24

Enzyme breaks down the hydrogen bonds between base pairs.
Separates strands to be used as a template.
“Unzips” DNA strand.

Answer 24

Helicase

Question 25

Enzyme that surrounds the “unzipped” separated strands of DNA and relax the twisting of helices. Relaxes DNA and controls supercooling (occurs as DNA double helix is unwound).

Answer 25

Topoisomerase

Question 26

Helicase unzips the strands and the DNA develops a “forked” structure, which lets replication happen.

Answer 26

DNA Replication Fork

Question 27

Enzyme builds short stretches of RNA called **primers** that are required to start elongation. Is the initializer. Required to lay down short stretches of RNA nucleotides that are complementary to the DNA template before DNA nucleotides can be added to the template.

Answer 27

Primase

Question 28

Enzyme responsible for forming new copies of DNA. Travels down the DNA strand. —> Works in the 5’ to 3’ direction. Adds DNA nucleotides complementary to the template strand to form the new strand of DNA.

Answer 28

DNA Polymerase

Question 29

DNA polymerase travels down the DNA strand and adds new nucleotides to each of the 2 DNA strands (leading strand and lagging strand).

Answer 29

Elongation

Question 30

DNA oriented in 5’ to 3’ direction. DNA polymerase adds the new nucleotides to the RNA primer and then to the newly synthesized DNA strand in a *continuous* fashion.

Answer 30

Leading Strand

Question 31

Antiparallel and runs in the 3’ to 5’ direction. —> DNA polymerase *MUST* work in the 5’ to 3’ direction. —> This leads to the creation of short, discontinuous fragments called **Okazaki fragments**.

Answer 31

Lagging Strand

Question 32

Short, discontinuous fragments on the lagging strand.

Answer 32

Okazaki Fragments

Question 33

Helps glue the Okazaki fragments together to form a complete DNA molecule. Joins Okazaki fragments together to create a continuous DNA strand.

Answer 33

Ligase

Question 34

Prokaryotic chromosome first replicates, then 2 copies of the chromosome associate with different part of the cell membrane, the the cell pulls apart into 2 identical cells. *Asexual reproduction.*

Answer 34

Binary Fission

Question 35

Difference between RNA and DNA:

Answer 35

RNA is a single helix, DNA is a double helix. RNA has uracil (U), DNA has thymine (T). RNA has the sugar ribose, DNA has the sugar deoxyribose. RNA has fewer base pairs than DNA.