Nucleic Acid Synthesis and Structure Flashcards Preview

Biochem Exam 1 > Nucleic Acid Synthesis and Structure > Flashcards

Flashcards in Nucleic Acid Synthesis and Structure Deck (41)
Loading flashcards...
1
Q

What are the purines

A

Adenine and Guanine

2
Q

What are the pyrimidines?

A

Cytosine, Thymine, and Uracil

3
Q

The difference between DNA and RNA is the presence of what functional group?

A

Hydroxyl (OH) group

4
Q

Linkage between 2 nucleotides?

A

phosphodiester bond

5
Q

5’ end contains what group?

A

Phosphate

6
Q

3’ end contains what group?

A

OH group

7
Q

A - T contains how many H-bonds?

A

2

8
Q

C - G contains how many H-bonds?

A

3

9
Q

Which base pairing is more stable?

A

G:C, more stacks

10
Q

DNA and RNA are held together by what type of bond?

A

Glycosidic bond

11
Q

Prokaryotes contain what ribosomal subunits?

A

50S + 30S

12
Q

Prokaryotes contain 3 types of rRNA

A

23, 16, and 5S

13
Q

Eukaryotes contain what ribosomal RNA subunits?

A

60S + 40S

14
Q

Eukaryotes contain 4 types of rRNA

A

28, 18, 5.8, and 5S

15
Q

What portion of the tRNA recognizes the codon on the mRNA

A

Anticodon loop

16
Q

What base pair has a higher Tm?

A

G:C

17
Q

What kind of solution will denature DNA, but break down RNA?

A

Basic solutions

18
Q

Histones are positively charged and contain what 2 AA’s that bind to DNA?

A

Arginine and lysine

19
Q

Zidovudine (ZDV) stops the action of what enzyme?

A

Reverse transcriptase

20
Q

5-Fluorouracil is used to stop DNA synthesis, specifically synthesis of what?

A

Thymine

21
Q

Azithromycin binds to what ribosomal subunit in bacteria?

A

50S

22
Q

In prokaryotes, DNA replication is initiated where?

A

oriC

23
Q

What DNA polymerase is used in prokaryotic DNA replication?

A

Pol III

24
Q

In eukaryotic DNA replication, what polymerase replicates the leading strand?

A

Pol epsilon (E)

25
Q

In eukaryotic DNA replication, what polymerase replicates the lagging strand?

A

Pol delta (D)

26
Q

Telomerase add NUCs to what end?

A

3’

27
Q

Methylation happens to what strand?

A

template strand

28
Q

Smoking causes damage to what part of the DNA?

A

Binds guanine, causing it to be bulky

29
Q

Sun exposure causes damage to what portion of the DNA?

A

Forms thymine dimers

30
Q

“Normal” causes of DNA damage are due to what type of reaction?

A

Deamination reaction

31
Q

In base excision repair, what enzyme removes the damaged base?

A

Glycosylase

32
Q

In BER what enzyme removes the deoxyribose?

A

exonuclease

33
Q

A thymine dimer would be fixed using what type of DNA repair mechanism?

A

Nucleotide Excision Repair (NER)

34
Q

What enzyme cleaves the distorted region in NER?

A

Endonuclease

35
Q

In mismatched repair, what determines which strand is repaired?

A

Methylation

36
Q

In mismatch repair, what strand is repaired?

A

Template strand

37
Q

What type of recombination is common in cancer cells?

A

Translocation

38
Q

Cytosine is converted to Uracil via what type of reaction?

A

Deamination

39
Q

Cytosine can be converted to what, via deamination?

A

Uracil

40
Q

What type of DNA repair mechanism would be used to fix a bulky guanine residue?

A

NER

41
Q

What is the function of primase?

A

Add a 3’ OH primer