9.3 - 9.4

Question 1

Transfer RNA nucleotides

Answer 1

74-95 nucleotides (short)

Question 2

Transfer RNA

Answer 2

small RNA adapter moelcule that, through complementary base pairing with codons in mRNA, places a specific amino acid at the correct position in a growing polypeptide chain at the ribosome

Question 3

tRNA secondary structur

Answer 3

cloverleaf

Question 4

tRNA tertiary structure

Answer 4

looks compact letter L

Question 5

anticodon

Answer 5

codon in tRNA molecules that recognize codon on the mRNA by complementary base pairing and wobble

Question 6

Amino acid is attached on

Answer 6

3’ end of tRNA

Question 7

Aminoacyl-tRNA synthetases

Answer 7

enzymes that catalyze the attachment of tRNAs to the amino acids that corresponds to tRNA’s anticodon, forming charged tRNAs

Question 8

Only molecules that read both nucleic acid and protein language

Answer 8

Aminoacyl-tRNA synthetases

Question 9

One Aminoacyl-tRNA synthetases exists for

Answer 9

each of the 20 common amino aicds

Question 10

Charged tRNA

Answer 10

a tRNA molecule to which the corresponding amino acid has been attached y an aminoacyl-tRNA synthetase (uses ATP)

Question 11

Bond between the amino acid and tRNA contains substantial energy that is later used to form

Answer 11

peptide bonds

Question 12

Amino acid attached to tRNA treated with nickel hydride

Answer 12

changes amino acid

Question 13

Treatment with nickel hydride on anticodon

Answer 13

leaves anticodon unchanged

Question 14

Specific interaction between a tRNA’s anticodon and mRNA’s codon determines

Answer 14

which amino acid is added to growing polypeptide chain

Question 15

Wobble

Answer 15

the ability of the 5’-most base of an anticodon to pair with more than one type of base at the 3’ ends of codons

Question 16

possible codon triplets in genetic code

Answer 16

61 possible codons

Question 17

E. Coli makes tRNAs containing 42 different anticodon

Answer 17

61-42 =19 of potential anticodons are not represented

Question 18

Do cells carry tRNA with anticodons complementary to all possible codons

Answer 18

no

Question 19

How can an organism construct proper polypeptides if some of the codon in its mRNAs cannot locate tRNAs with complementary anticodons?

Answer 19

Some tRNAs can recognize more than one codon for the amino acid with which they are charged

Question 20

U in the 5’ end of tRNA can bind

Answer 20

A or G in the codon 3’ end

Question 21

G in the 5’ end of the tRNA can

Answer 21

U or C in the codon’s 3’ end

Question 22

I (inosine) in the 5’ end pf tRNA can bind

Answer 22

A, U or C in the codon’s 3’ end

Question 23

Ribosome in eukaryotic

Answer 23

80S

Question 24

Ribosome in prokaryotic

Answer 24

70S

Question 25

Small subunit of ribosome

Answer 25

binds to mRNA

Question 26

Site of polypeptide synthesis

Answer 26

ribosomes

Question 27

Large subunit of ribosome

Answer 27

has peptidy transferase activity

Question 28

Parts of karge subunit of rubosome

Answer 28

Aminoacyl (A) site, Peptidy (P) site, Exit (E) site

Question 29

in prokaryotic what is the first amino acid in the polypeptide chain

Answer 29

N-formyl-methionine

Question 30

Translation of mRNAs on ribosomes for prokaryotes, during initiation phase what does ribosomes bind to

Answer 30

Shine-Dalgarno box and an AUG

Question 31

Shine-Dalgarno box

Answer 31

5' - AGGAGG - 3'

Question 32

Translation of mRNAs on ribosomes for eukaryotes, during initiation

Answer 32

small ribosomal subunits binds to 5' cap, then migrates to the first AUG codon

Question 33

Elongation phase in ribosomes

Answer 33

addition of AA to C-terminus of polypeptide

Question 34

Termination phase in ribosomes

Answer 34

No normal tRNAs carry anticodons for the stop codons Release factors bind to the stop codon Release of ribosomal subunits, mRNA, and polypeptide

Question 35

Posttranslational processing

Answer 35

Enzymatic cleavage Addition of chemical constituents

Question 36

Enhancers can be located

Answer 36

upstream, downstream or within coding region or intron of a gene

Question 37

Enhancers

Answer 37

Stabilize RNA polymerase at promoter and enhancers clear histones from promoter

Question 38

Prokaryotic translation

Answer 38

Multiple ribosomes binding sites and can direct synthesis of several different polypeptide and immediatiely binds to binding site of mRNA