Lecture 20 - Nucleotide Structure Flashcards Preview

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

The "acid" portion of DNA or RNA arise from _____.

the phosphate/phosphoric acid

2

Nucleic acids are nucleotides attached to a _____.

sugar-phosphate backbone

3

Describe the sugar-phosphate backbone

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

4

The sugar backbone is comprised of ______ bonds.

phosphodiester

5

Describe the hydrogen bonding in base pairing of nucleotides

A2T; G3C

6

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

the M-phase (chromosome segregation)

7

Uncoiled DNA is found in what phase of mitosis?

The I-phase (interphase)

8

Histone proteins + nuclear DNA is called _____.

chromatin

9

What differentiates ribose from deoxyribose sugars?

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

10

Bases + sugar = ______

nucleoside

11

base + sugar + phosphate = _________

nucleotides

12

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

small (Memory aid: big name, small ring)

13

Memory aid for purine and pyrimidine:

Pure As Gold: Purine - adenine, guanine

14

Reduces ribose sugars to deoxyribose sugars.

ribonucleotide reductase (removes C2 -OH group)

15

Why is production of nucleotides a highly energy favorable process?

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

16

Name and f(x)?

Q image thumb

- Coenzyme-A

- synthesis and beta-oxidation of fatty acids - pyruvate oxidation

17

Name and F(x)?

Q image thumb

- NAD

- acts as an electron carrier in redox reactions to form NADH

18

Name and F(x)?

Q image thumb

- FAD

- Participates in redox reactions ot accept 2e to form FADH2

19

DNA/RNA is synthesized in the ______ direction.

5'-3'

20

Carbon 1 of sugar contains _____.

N-base

21

Carbon 2 of sugar contains ______.

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

22

Carbon 3 of sugar contains _____.

-OH group; forms phosphodiester bond with C5

23

Carbon 5 of sugar contains ______.

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

24

One turn of DNA is approximately ____ in length.

34 angstroms

25

How may base pairs per turn?

10 (~ every 3.4 angstroms)

26

What increased nucleotide ratio increases denaturation temperature? Why?

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

27

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

reverse transcriptase

28

Enzyme that cleaves nucleic acid into oligomers (insert picture)

ribonuclease/deoxyribonuclease

29

Cleaves phosphdiester backbone (insert picture)

phosphdiesterase

30

Cleaves phosphate from nucleotide

nucleotidase (cleaves nucleotide to Pi and nucleoside

31

Cleaves base from nucleoside

Nucleosidase

32

Phosphodiesterase produces what oligomer?

nucleotide monophosphate (NMPs) or deoxynucleoside monophosphates (dNMPs)

33

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

nucleotide

34

What same atom sources are shared between pyrimidines and purines?

Amino acids

35

How do pyrimidine and purine carbon sources differ?

Pyrimidine: HCO3

Purine: CO2

 

(Longer N-base = "longer" carbon source)

36

How do pyrimidine and purine THF sources differ?

Purine: formyl THF

Pyrimidine: methylene THF

 

Longer N-base = longer THF form

37

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

a) alpha-glycosidic linkage

b) beta-glycosidic linkage

c) delta-glycosidic linkage

b) beta-glycosidic linkage

38