Module 4 (Nucleic Acids and Information Flow)

Question 1

Function of DNA

Answer 1

Storing genetic information, copying itself to transmit the genetic information from one generation to the next

Question 2

F. Griffith (1928)

Answer 2

Made experiment where a dead virulent bacteria mixed with live bacteria that was non-virulent transformed harmless bacteria into harmful bacteria.

Question 3

Streptococcus pneumoniae

Answer 3

What type of bacteria did F. Griffith use?

Question 4

Avery, MacLeod, McCarty

Answer 4

Determined that DNA was responsible for the transfer of genetic information

Question 5

Deoxyribose

Answer 5

2’ carbon “minus oxygen”
Component of DNA

Question 6

Nucleoside

Answer 6

Base and a sugar

Question 7

Nucleotide

Answer 7

Base, sugar and phosphate

Question 8

What contributes to the stability of DNA?

Answer 8

Hydrogen bonds, and base stacking

Question 9

Replication

Answer 9

How DNA copies itself to pass along genetic information to the next generation

Question 10

Fidelity

Answer 10

The degree of exactness with which something is copied

Question 11

Parental Strands

Answer 11

The original DNA strand

Question 12

Daughter strand

Answer 12

The strand of DNA that is newly replicated from an existing template strand of DNA

Question 13

Reverse Transcriptase

Answer 13

Catalyzes the reaction of RNA to DNA

Question 14

Polarity

Answer 14

Difference between two ends of strands of DNA

Question 15

Bases can only be added to __________ on the sugar

Answer 15

3’ Carbon

Question 16

DNA is synthesized in a _______ direction

Answer 16

5’-3’

Question 17

Watson and Crick

Answer 17

Used other researcher’s data to create a 3D model of DNA

Question 18

Rosalind Franklin and Maurice Wilkins

Answer 18

Used x-ray crystallography to study DNA structure

Question 19

Erwin Chargaff

Answer 19

Discovered that DNA composition varies, but the amount of adenine is always the same as thymine and the amount of cytosine is always the same as guanine.

Question 20

Base stacking

Answer 20

Stabilizing hydrophobic interactions between bases in the same strand of DNA. (non-polar)

Question 21

Hydrogen bonds in DNA

Answer 21

Create stability in the DNA molecule in numbers

Question 22

Central Dogma

Answer 22

DNA -> RNA -> Protein

Question 23

Reverse Transcription

Answer 23

RNA -> DNA
RNA template for the synthesis of DNA

Question 24

Gene

Answer 24

“The unit of heredity affecting one or more traits of an organism; the DNA sequence that corresponds to a specific protein”

Question 25

Gene expression

Answer 25

The production of a functional gene produce, such as a protein, is regulated

Question 26

Nucleus

Answer 26

Transcription occurs here in eukaryotes

Question 27

Cytoplasm

Answer 27

Where transcription occurs in Prokaryotic cells

Question 28

The 5' end of a RNA strand

Answer 28

A triphosphate

Question 29

Why is RNA less stable?

Answer 29

The -OH group on 2' Carbon on RNA makes it easier to break down

Question 30

Transcription

Answer 30

Copying a DNA sequence into an RNA sequence

Question 31

Why does RNA break down easier?

Answer 31

Because of the OH group on the 2' carbon, it makes it susceptible to hydrolysis.

Question 32

5' of RNA is ....

Answer 32

Typically a triphosphate

Question 33

5' end of DNA is ...

Answer 33

Typically a monophosphate

Question 34

Hairpin Turn

Answer 34

The folding of RNA, where RNA bases interact with each other ex. tRNA

Question 35

What is the difference between Uracil and Thymine?

Answer 35

Uracil has a hydrogen where Thymine has a methyl (-CH3) group

Question 36

What is needed for transcription to occur?

Answer 36

* A DNA template * RNA polymerase (enzyme)

Question 37

Stages of Transciption

Answer 37

Initiation, Elongation, Termination

Question 38

Where is Transcription initiated?

Answer 38

The promoter sequence

Question 39

TATA box

Answer 39

Common promoter sequence in eukaryotes

Question 40

Sigma factor

Answer 40

A protein that is responsible for promoter recognition in bacteria. - Works with RNA polymerase

Question 41

General transcription factors

Answer 41

Proteins that are responsible to initiate transcription in Eukaryotes (at least 6) - Bind to promoter region

Question 42

Where do transcriptional activator proteins bind to?

Answer 42

They bind to enhancer sequences on DNA, recruit RNA polymerase complex II

Question 43

Why does the looping of the DNA do for transcription?

Answer 43

DNA brings activator proteins into contact with the proteins bound at the promoter region, causes transcription to start.

Question 44

Transcription Elongation

Answer 44

RNA Pol (prokaryotes) and RNA Pol II (eukaryotes) allows for unwinding of DNA - RNA nucleotide triphosphates can enter via channels - RNA polymerase detects the ribonucleoside triphosphate, makes sure it pairs properly - Orients O in OH group to 3' end of strand, two phosphates cleaved (energy for reaction)

Question 45

Pyrophosphate group

Answer 45

Phosphate group - phosphate group

Question 46

Primary Transcript

Answer 46

RNA transcript that comes off the template DNA strand

Question 47

Location of transcription in prokaryotes

Answer 47

Both occur in the cytoplasm

Question 48

Polycistronic mRNA

Answer 48

In prokaryotes, primary transcripts may contain information for more than one gene

Question 49

5' Cap

Answer 49

7-methylguanosine to the 5' end of mRNA - Unique 5'-5' bond, protects mRNA from exonucleases and stability - Required for ribosome to recognize mRNA

Question 50

Poly (A) Tail

Answer 50

Polyadenylation - Approx 250 A bases to 3' end of mRNA - Protection from degradation - Transcription termination

Question 51

Alternative Splicing

Answer 51

Removing Introns from mRNA sequence