Lecture 20 - Nucleotide Structure Flashcards Preview

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Flashcards in Lecture 20 - Nucleotide Structure Deck (38)
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1
Q

The “acid” portion of DNA or RNA arise from _____.

A

the phosphate/phosphoric acid

2
Q

Nucleic acids are nucleotides attached to a _____.

A

sugar-phosphate backbone

3
Q

Describe the sugar-phosphate backbone

A

the 5’ phosphate group of one nucleotide is attached to the 3’ -OH of another nucleotide

4
Q

The sugar backbone is comprised of ______ bonds.

A

phosphodiester

5
Q

Describe the hydrogen bonding in base pairing of nucleotides

A

A2T; G3C

6
Q

The fully folded chromosome is found in what stage of mitosis?

A

the M-phase (chromosome segregation)

7
Q

Uncoiled DNA is found in what phase of mitosis?

A

The I-phase (interphase)

8
Q

Histone proteins + nuclear DNA is called _____.

A

chromatin

9
Q

What differentiates ribose from deoxyribose sugars?

A

Ribose has a C2 and C3 -OH group; Deooxyribose has only a C3 -OH group

10
Q

Bases + sugar = ______

A

nucleoside

11
Q

base + sugar + phosphate = _________

A

nucleotides

12
Q

Pyrimidines are the (large/small) ring stucture of nitrogenous bases.

A

small (Memory aid: big name, small ring)

13
Q

Memory aid for purine and pyrimidine:

A

Pure As Gold: Purine - adenine, guanine

14
Q

Reduces ribose sugars to deoxyribose sugars.

A

ribonucleotide reductase (removes C2 -OH group)

15
Q

Why is production of nucleotides a highly energy favorable process?

A

Most nucleotides exist as a triphosphate. Cleavage of 2 Pi release energy and forms a nucleotide

16
Q

Name and f(x)?

A
  • Coenzyme-A
  • synthesis and beta-oxidation of fatty acids - pyruvate oxidation
17
Q

Name and F(x)?

A
  • NAD
  • acts as an electron carrier in redox reactions to form NADH
18
Q

Name and F(x)?

A
  • FAD
  • Participates in redox reactions ot accept 2e to form FADH2
19
Q

DNA/RNA is synthesized in the ______ direction.

A

5’-3’

20
Q

Carbon 1 of sugar contains _____.

A

N-base

21
Q

Carbon 2 of sugar contains ______.

A

either -H or -OH (deoxy vs ribose sugar)

22
Q

Carbon 3 of sugar contains _____.

A

-OH group; forms phosphodiester bond with C5

23
Q

Carbon 5 of sugar contains ______.

A

Phosphate group (binds with C3 -OH to form phosphodiester bond)

24
Q

One turn of DNA is approximately ____ in length.

A

34 angstroms

25
Q

How may base pairs per turn?

A

10 (~ every 3.4 angstroms)

26
Q

What increased nucleotide ratio increases denaturation temperature? Why?

A

Increased G:C. Because G:C has 3 H-bonds, compared to the 2 H-bonds of A:T

27
Q

Coded for by viral genome. Assists in virus replication by making DNA from RNA

A

reverse transcriptase

28
Q

Enzyme that cleaves nucleic acid into oligomers (insert picture)

A

ribonuclease/deoxyribonuclease

29
Q

Cleaves phosphdiester backbone (insert picture)

A

phosphdiesterase

30
Q

Cleaves phosphate from nucleotide

A

nucleotidase (cleaves nucleotide to Pi and nucleoside

31
Q

Cleaves base from nucleoside

A

Nucleosidase

32
Q

Phosphodiesterase produces what oligomer?

A

nucleotide monophosphate (NMPs) or deoxynucleoside monophosphates (dNMPs)

33
Q

Phosphoric acid, ribose sugar, and base is called a ______.

A

nucleotide

34
Q

What same atom sources are shared between pyrimidines and purines?

A

Amino acids

35
Q

How do pyrimidine and purine carbon sources differ?

A

Pyrimidine: HCO3

Purine: CO2

(Longer N-base = “longer” carbon source)

36
Q

How do pyrimidine and purine THF sources differ?

A

Purine: formyl THF

Pyrimidine: methylene THF

Longer N-base = longer THF form

37
Q

Sugars are attached to nitrogenous bases by what type of linkage?

a) alpha-glycosidic linkage
b) beta-glycosidic linkage
c) delta-glycosidic linkage

A

b) beta-glycosidic linkage

38
Q
A