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Flashcards in Nucleotides And Genetics Deck (79):
1

Nucleotides with pyrimidine bases

CUT the Pie
Cytosine
Uracil
Thymine

2

Nucleotides with Purine bases

Pure as gold
Adenine
Guanine

3

In nucleotides, the phosphoryl group is attached to which carbon in the pentose?

C5

4

Most nucleosides are linked to a purine or pyrimidine through what bond

B-N glycosidic bond

5

Rate limiting enzyme of purine synthesis

PRPP glutamyl amidotransferase

6

Rate limiting enzyme of pyrimidine synthesis

Carbamoyl phosphate synthetase 2

7

Donors of atoms in purine synthesis

Gold Tarnished puRING

Glycine
Tetrahydrofolate

8

Donors of atoms in pyrimidine synthesis

Cut the pie and put it in a CAGe

Glutamine
Aspartate
CO2

9

Parent molecule in purine synthesis

Inosine monophosphate

10

Parent molecule in pyrimidine synthesis

Orotidine monophosphate

11

Enzymes in pyrimidine synthesis

Ricbonucleotide reductase
Thymidylate synthase

12

What enzyme converts ribose 5 phosphate to PRPP?

PRPP synthetase

13

Enzymes inhibited by 5FU

Thymidylate synthase

14

Purine rings cannot be cleaved in human cells so it is converted into

Uric acid

15

Disease associated with accumulation of purines

Gout

16

Pyrimidines can be converted into these products for degradation

B-alanine: precursor of acetyl CoA
B- aminoisobutyrate: precursor of succinyl CoA

17

What is the source of ribose 5 phosphate

PRPP

18

Irreversible enzymes of purine salvage pathway

APRT
HGPRT

19

Highly repetitive sequences at the end of chromosomes

Telomeres

20

Form of DNA with 11 base pairs and right handed helix

A DNA

21

Form of DNA with 10 base pairs per turn

Right handed helix

B DNA

22

Form of DNA with left handed helix and 12 base pairs

Z DNA

23

Chargaff's rule applies to RNA or DNA?

DNA

24

Most common form of DNA

B DNA

25

RNA that serves as the template for protein synthesis

Messenger RNA

26

In eukaryotes, the methylguanosine cap of RNA is in the

5' end

27

The poly A tail of RNA is in what end?

3' end

28

RNA that is the Site for protein synthesis

Ribosomal RNA

29

RNA that translates nucleotide sequence of mRNA into specific amino acids

Transfer RNA

30

This RNA has 74-95 nucleotides and 20 different species

Contains the antocodon and cloverleaf appearance in 2D

Transfer RNA

31

RNA involved in splicing, removal of introns

Small nuclear RNA (snRNA)

32

RNA that inhibit gene expression

Micro RNA
Silencing RNA

33

DNA replication occurs in this phase of the cell cycle

S phase

34

The origin of replication is recognized by

Origin recognition complex

35

Unwinds the double helix in a process that is driven by ATP

Helicase

36

This maintains the separation of parent strands in DNA replication

Scotch tape
DNA binding proteins

37

This relieves the torsional strain from helicase induced unwinding

Gupit the buhol

Topoisomerase I

38

This synthesizes short segmentd of complementary RNA primers

Primase

39

Elongates the DNA strand by adding new deoxyribonuscleotides

DNA polymerase III

40

Okazaki fragments is found in which strand

Lagging strand

41

Mismatched nucleotides are removed using DNA polymerase III enzyme's

Proofreading

3-5' exonuclease

42

When another primer is reached this enzyme removes the ribonucleotides using 5-3' exonuclease and fills the gap

DNA polymerase 1

43

Seals the nick by catalyzing the formation of the last phosphodiester bond, requiring hydrolysis of ATP

DNA ligase

44

RNA primers are removed by these enzymes in eukaryotes

RNase H and FEN 1

45

This process involves the synthesis of RNA using DNA as template

Transcription

46

In the initiation step of RNA synthesis, RNA polymerase binds to DNA promoter sequences.

What are the promoter sequences in prokaryotes?

-35 sequence
Pribnow box

47

In the initiation step of RNA synthesis, RNA polymerase binds to DNA promoter sequences.

What are the promoter sequences in eukaryotes?

TATA or hogness box
CAAT box

Hog and cat in eukaryotes

48

In RNA initiation step, unwinding of DNA occurs to form a

Transcription bubble

49

Elongation of RNA is continuous until a termintation signal is reached like

Hairpin loop

50

Removal of introns and splicing of exons, and RNA changes are all part of

Post transcriptional modifications

51

RNA post transcriptional modification involves addition of

Poly A or CCA tail
Addition of 7 methylguanosine cap

52

Part of bacterial chromosome thag controls the synthesis of enzymes involved in lactose metabolism

Lactose operon

53

A codon consists of how many bases?

3 bases

54

How many codons are present in total?

64 codons

55

What are the stop codons?

UAG
UAA
UGA

56

Start codon for methionine

AUG

57

What are the characteristics of the genetic code?

DUNU

I DUNU
Degenerate
Unambiguous
Nonoverlapping
Universal

58

Characteristic of the genetic code that says that multiple codons can code for the same amino acid

Degenerate

59

Genetic code characteristic that says that a specific codon always codes for the same amino acid

Unambiguous

60

Characteristic of the genetic code that reads the codon in a continuing sequence until a stop codon is reached

Nonoverlapping

61

Characteristic of the genetic code that has been conserved from the very early stages of evolution

Universal

62

Contains the first codon in initiation step of Protein synthesis

Aminoacyl tRNA

63

Charging of amino acids by synthetases requires

2 ATP

64

Binding site for incoming tRNA

A site

65

Site occupied by peptidyl tRNA in initiation

P site

66

Site occupied by empty tRNA

E site

67

A cyclic process on the ribosome where one amino acid at a time is added to the peptide chain

Elongation

68

Peptide bond formation is elongation is catalyzed by

Peptidyltransferase

69

Allows a single tRNA to recognize more than one codon

Accurate base pairing required only on the 1st two nucleotide positions of mRNA codon

tRNA wobble

70

Energy required for protein synthesis

4 high energy bonds
2 from tRNA aminoacylation
1 from loading tRNA to ribosome
1 from translocation

71

Proteins that are defective are marked for destruction by

Ubiquitin

72

Defectives proteins are degraded by

Proteasomes

73

Type of mutation where new codons code for the same amino acid
No effect on protein

Silent mutation

74

Type of mutation where new codons codes for a different amino acid with variable effect on protein

Missense mutation

75

Type of mutation where the new codon is a stop codon

Nonsense mutation

76

Type of point mutation where there is purine-purine or pyrimidine- pyrimidine exchange

Transition

77

Point mutation where there is pyrimidine-purine or purine-pyrimidine exchange

Transversion

78

Type of mutation where there is deletion or addition of bases that results to shorter than normal, non functional protein

Frame shift mutation

79

Expansions in coding regions that cause the protein product to be longer than normal or unstable

Show anticipation in pedigree

Triple repeat expansion