Translation

Question 1

Translation

Answer 1

process of translating the language of nucleotides into the language of amino acids

Question 2

Where does translation occur?

Answer 2

ribosome via. instructions provided by mRNA

Question 3

mRNA is translated in what direction?

Answer 3

5’ to 3’

Question 4

mRNA is translated into

Answer 4

proteins

Question 5

start codon for translation

Answer 5

AUG (methionine)

Question 6

Codon

Answer 6

genetic code is read in groups of 3 nucleotides

Question 7

The degenerate nature of the genetic code

Answer 7

more than one codon can code for the same amino acid

Question 8

Unambiguous nature of genetic code

Answer 8

each codon only specifies one amino acid

Question 9

wobble

Answer 9

third base deviates from the base pairing rules or is an unusual base

Question 10

mutations

Answer 10

arise as a result of DNA damage or incorrect incorporation of bases

Question 11

point mutation (substitution)

Answer 11

a single base changes (CGA –> CGG)

Question 12

silent mutation

Answer 12

a change that specifies the same amino acid (CGA –> CGG)

Question 13

missense mutation

Answer 13

a change that specifies a different amino acid (CGA –> CCA)

Question 14

nonsense mutation

Answer 14

A change that produces a stop codon (CGA –> UGA)

Question 15

insertion mutation

Answer 15

an addition of one or more bases (CGAG –> CFATG)

Question 16

deletion mutation

Answer 16

A loss of one or more bases (CGAG –> CGG)

Question 17

frameshift mutation

Answer 17

mutation that shifts the reading frame of the genetic message by inserting or deleting a nucleotide

Question 18

proceeding of translation

Answer 18

• charged tRNAs donate their aa to the growing chain while the anticodon is attached to the mRNA
• tRNA is released and charged tRNA codes for the next aa in the reading frame becomes attached

Question 19

3 steps of translation

Answer 19

initiation, elongation, termination

Question 20

initiation

Answer 20

formation of a complex between the methionyl-tRNA, initiation factors, the mRNA, and thee smallest ribosomal subunit (40S), 60S subunit binds to complete

Question 21

binding sites on ribosome

Answer 21

A (aminoacyl), P (peptidyl),

Question 22

Elongation

Answer 22

peptidyltransderase, the rRNA of the large ribosomal subunit catalyzes the formation of the peptide bond

Question 23

termination

Answer 23

• stop codon reached (UGA, UAG, UAA)
• release factors bind to ribosome, allowing last peptide bond to form before ribosome falls apart and releases protein
• requires lots of energy

Question 24

posttranslational modification

Answer 24

removal of N-terminal methionine, cleavage

Question 25

polysomes

Answer 25

multiple ribosome can attach to an mRNA, each producing the same protein

Question 26

signal sequence

Answer 26

sequence within a protein that directs the protein to a particular organelle

Question 27

Signal-reecognition particle (SRP)

Answer 27

• secreted or incorporated membrane proteins are translated in the ER due to SRP
• cause the ribosome to dock onto the ER to complete synthesis of the protein

Question 28

proteins synthesized into the ER

Answer 28

travel in vesicle to Golgi complex, but do not remain, become lysosomes or fuse within the cell membrane