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0

A protein is synthesized in the

amino to carboxyl direction by the sequential addition of amino acids to the carboxyl end of the growing peptide chain

1

What is a set of rules that covert the nucleotide sequence of a gene inot the amino acid sequence of protein

genetic code

2

What is teh genetic code intermediary?

mNA

3

How is the sequence of nucleotides in the mRNA molecule read?

consecutively in groups of three

4

What is each group of 3 consecutive nucleotides in RNA called?

a codon

5

What does a codon specify?

Either one amino acid or a stop to the translation process

6

How many total codons?

61 triplet codons code for the 20 known amino acids, thus the cod is degenerate

7

What does degenerate mean?

More than one codon per amino acid

8

How does an amino acid recognize a codon?

tRNA

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How can the codons in mRNA be translated into a protein?

...

10

What is the adaptor hypothesis?

It postulates that the genetic code is read by molecules that can recognize a codon and carry the corresponding amino acide

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What does transfer RNA or tRNA do?

serves as an adaptor that binds to a specific codon and brings iwth it an amino acid for incorporation into the polypeptide chain

12

What is the secondary structure of tRNA?

cloverleaf... tRNA fold up into a defined 3D strucutre an contains 4 short double helical segments

13

What are two regions of of tRNA?

two regions of unpaired nucleotides are curitcial to the function

14

What is the anticodon loop of tRna?

a set of 3 consecutive nuclellotides that pair with a compelnetary....

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....

...

16

Are there more than one tRNA for most amino acids?

yes

17

Some tRNAs require accurate base pairing only at?

the first two positions of the codon and can tolerate a mismatch?

18

What is it called when it can tolerate a mismatch?

wobble hypthesis

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What does the wobble base pairing explain/

Why so many of the alternative....

20

Amino acid reacts with? for the activation of adenylated amino acid?

ATP looses 2 phosphates...

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adenylated amino acid is?

amino acid-AMP

22

What is the recognition and attachment of the correct amino acid to the corresponding tRNA catalyzed by?

aminoacyl-tRNA synthestases

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What does aminoacyl-tRNA synthatase do?

...

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....

....

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....

....

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at tRNA level there is a bonding site for the?

anti codon

27

Editing (hydrolytic) site cleaves .... speicies that are .... than the correct one

activated, smaller

28

What raises the overal accuracy of tRNA chargin to approximately on mistake in 40,000 coupling

hydrolytic editing.... this is on the snythatase

29

What is the genetic code translated by?

two adaptors

30

What are the two adaptors?

tRNA and the tRNA synthetase

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What contains highly discriminating amino acid

....

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....

....

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....

....

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...

...

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Prokaryotic ribosome

70s... small subunit

36

eukaryotic ribosome

80s and small subunit

37

What is a ribosome?

A complex catalytic machine, consiting of two subuits

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What does each ribosome subunit consist of?

Different ribosomal proteins and several ribosomeal RNAs (rRNAs)

39

What determin the overall shape of the ribosome?

rRNAs
-its ability to postition tRNAs on the mRNA, adn it scatalytic activity in forming peptide bonds

40

small subunit?

provides...

41

large subunit

...

42

Protein synthesis is performed on?

the ribosome
- it ensures accuracy and maintains correct reading frame

43

What are separate when not snythesizing proteins?

the 2 ribosomes su

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How are the ribosomes subunits joined/

join together at the 5' end of mRNA and initaed protien snythesis

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What direction is teh ribosoem pulled through?

5-3 direction

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...

...

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...

...

48

Where does the ribosome making occur?

cytosol

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What is a polyribosome?

...

50

What contains 4 binding sites for RNA

ribosomes

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what are the three tRNA sites?

A(aminoacyl)
P(peptidyl)
E(exit)

52

What is the 4ths bieing site for?

mRNA

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The A, P and E site

....

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....

....

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....

...

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What is teh fundamental reaction of protein snythesis?

The formation of peptide bond btw amino acids

57

Where does the reaction of protein snythsis occur?

...

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...

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