DNA as the Genetic Material

Question 1

the belief that genetic material passed down from parents to their children exists in the _____ and these structures explain inheritance patterns

Answer 1

Chromosome Inheritance Theory

Question 2

Discovered the 3 major components that make up a nucleotide and how DNA and RNA are put together

Answer 2

Phoebus Levene

Question 3

What 3 things are nucleotides made up of?

Answer 3

1. Phosphate group
2. Sugar
3. Nitrogenous Bases

Question 4

the amount of adenine is roughly equal to that amount of thymine and the amount of cytosine is about the same as the amount of guanine

Answer 4

Chargaff’s Rule

Question 5

What do mispairings between bases, that aren’t detected and corrected by enzymes during replication, result in?

Answer 5

Mutations

Question 6

the process of beaming x-rays onto a crystalline molecule to measure how the molecule bends the beams and then using those measurements to develop a 3D picture of the structure of the molecule

Answer 6

X-ray Crystallography

Question 7

Who first used x-ray crystallography to photograph the 3D structure of DNA?

Answer 7

Rosalind Franklin

Question 8

A double helix is composed of what 2 things?

Answer 8

1. 2 very long sugar-phosphate backbones
2. Base pairs

Question 9

the 2 helical strands run parallel to each other but go in opposite directions

Answer 9

Antiparallel

Question 10

What type of bonding is used in DNA structures?

Answer 10

Hydrogen Bonding

Question 11

Why is hydrogen bonding important to DNA structure? List 3 things

Answer 11

1. Allows the characteristic ladder shape to form
2. This bonding is strong enough to hold the bases together
3. This bonding is weak enough to break when needed

Question 12

a nitrogenous base and a sugar without a phosphate

Answer 12

Nucleoside

Question 13

a nitrogenous base, a sugar, and 1-3 phosphates

Answer 13

Nucleotide

Question 14

DNA is an array of what?

Answer 14

Nucleotides

Question 15

What 3 properties make DNA critically important to life?

Answer 15

1. DNA can be copied
2. DNA carries information and contains instructions for all the characteristics an organism will exhibit
3. DNA can mutate and recombine > help an organism adapt and survive in a dynamic environment

Question 16

the process of copying DNA

Answer 16

Replication

Question 17

What 3 things is DNA replication essential for?

Answer 17

1. Cell Growth
2. Cell Repair
3. Cell Reproduction

Question 18

a series of events that leads to DNA replication and the division of cytoplasm and organelles to produce 2 daughter cells

Answer 18

Cell Cycle

Question 19

Name the 2 main stages of the cell cycle?

Answer 19

1. Interphase
2. Mitosis

Question 20

the process of copying DNA that results in each DNA molecule being made up of 1 old conserved strand of DNA and 1 newly synthesized one

Answer 20

Semiconservative DNA Replication

Question 21

a DNA sequence with altered nucleotides

Answer 21

Mutation

Question 22

a lab analysis that detects whether the DNA of the bacteria or virus is present in the patient to let you know which disease is causing the symptoms

Answer 22

Polymerase Chain Reaction Test (PCR Test)

Question 23

How does a PCR test work?

Answer 23

It replicates small pieces of DNA many times > replicating the DNA from a virus or bacteria make the DNA much easier to find

Question 24

commonly performed in canine patients to screen for this bacterial infection that can cause kidney and liver failure

Answer 24

Leptospirosis PCR

Question 25

What are the 3 main stages in DNA replication?

Answer 25

1. Initiation 2. Elongation 3. Termination

Question 26

the phase of DNA replication in which a location on the DNA double helix is targeted for unwinding and the parent DNA is separated into 2 strands

Answer 26

Initiation

Question 27

the phase of DNA replication in which new nucleotides are added to the newly synthesized DNA strands

Answer 27

Elongation

Question 28

the phase of DNA replication that follows Elongation and ends the process

Answer 28

Termination

Question 29

What are the 8 steps to DNA replication?

Answer 29

1. Helicases breaks the hydrogen bonds between base pairs + other proteins keep the single strands of DNA from joining again 2. Topoisomerases surround the "unzipped" separated strands of DNA and relax the twisting of the helices 3. After helicase unzips the strands, the DNA replication fork forms 4. Primase builds short stretches of RNA primers to start Elongation 5. DNA polymerase starts where primase added RNA primers and adds new nucleotides to the RNA primers on each of the 2 newly synthesized DNA strand (different for leading and lagging strand) 6. Ligase completes the sugar-phosphate backbone at nicks in the newly synthesized DNA between the Okazaki fragments to form a complete daughter DNA molecule 7. RNA primers are removed and replaced with DNA 8. The newly synthesized DNA is checked for any mistakes that may have occurred during replication

Question 30

enzymes that unwind DNA at the origin of replication by breaking the hydrogen bonds between 2 DNA strands

Answer 30

Helicase

Question 31

the specific point at which DNA begins to unwind in order to begin replication

Answer 31

Origin of Replication (DNA Replication Fork)

Question 32

an enzyme that adds RNA Primers to a parent strand of DNA and acts as the initializer for DNA replication

Answer 32

Primase

Question 33

enzymes that relieve the tension created by helicase and break the phosphodiester bonds between the nucleotides in the DNA backbone

Answer 33

Topoisomerase

Question 34

the new strand of DNA that is made in fragments due to it running in the opposite direction as the parent DNA strand and runs 3' to 5'

Answer 34

Lagging Strand

Question 35

the new strand of DNA that is made continuously due to it running in the same direction as the parent DNA strand and runs 5' to 3

Answer 35

Leading Strand

Question 36

necessary for DNA polymerase to be able to bind and start the elongation process

Answer 36

RNA Primers

Question 37

the enzyme that adds the appropriate nitrogenous base pairs to the template strand of DNA in order to create the complementary strand and must work in the 5' to 3' direction

Answer 37

DNA Polymerase

Question 38

short discontinuous chunks of nitrogenous base pairs added to the lagging strand during semi-conservative replication

Answer 38

Okazaki Fragments

Question 39

enzymes that help glue the Okazaki fragments together to form a complete daughter DNA molecule

Answer 39

Ligase

Question 40

Discovered that DNA bases pair with each other and that the amount of each base is equal and that the rule of base pairing is true in other species

Answer 40

Erwin Chargaff

Question 41

experiment that demonstrated that DNA replicates in a semi-conservative manner

Answer 41

Meselson-Stahl Experiment

Question 42

Explain in 3 steps how the Meselson-Stahl Experiment demonstrated that DNA replicates semi-conservatively

Answer 42

1. They labeled some DNA with nitrogen-15 (an isotope of nitrogen) in a solution 2. They measured the density to determine how much nitrogen-15 was in the solution after each replication > isotopes are heavier than the normal element 3. After each DNA replication, the labeled strands became rarer

Question 43

a type of asexual reproduction and is the mechanism by which prokaryotic cells divide and results in offspring that are genetically identical to the parent

Answer 43

Binary Fission

Question 44

What are the 3 steps to Binary Fission?

Answer 44

1. The prokaryotic chromosome replicates 2. The 2 copies of the chromosome associate with different parts of the cell membrane 3. The cell pulls apart into 2 identical cells, each containing a copy of the prokaryotic genome

Question 45

List 5 similarities between RNA and DNA

Answer 45

Both: 1. are nucleic acids 2. are made of chains of nucleotides 3. form nucleotides in the same way 4. form nucleic acids in the same way 5. have cytosine, guanine, and adenine bases

Question 46

List 4 differences between RNA and DNA

Answer 46

1. Ribose (RNA) vs Deoxyribose (DNA) 2. Uracil Base (RNA) vs Thymine Base (DNA) 3. Single Helix (RNA) vs Double Helix (DNA) 4. Short Polymer (RNA) vs Long Polymer (DNA)

Question 47

What indicates the length of a polymer?

Answer 47

The number of base pairs Less base pairs = shorter polymer

Question 48

How many hydrogen bonds are between adenine and uracil?

Answer 48

2

Question 49

How many hydrogen bonds are between adenine and thymine?

Answer 49

2

Question 50

How many hydrogen bonds are between cytosine and guanine?

Answer 50

3