Quiz 8- CH 15

Question 1

Protein

Answer 1

building block of all living organism

Question 2

amino acid

Answer 2

building blocks of all proteins
joined by peptide bonds

Question 3

polypeptide

Answer 3

a string of amino acids
protein

Question 4

components of an amino acid

Answer 4

A C w 4 groups attached
- H
- amino group
- carboxyl group
- R group

Question 5

possible R groups

Answer 5

non polar
polar
aromatic
positively charged
negatively charged

Question 6

levels of organization

Answer 6

20 diff amino acids with millions of possible combos
newly synthesized proteins must be correctly folded
primary
secondary
tertiary
quaternary (functional)

Question 7

Translation

Answer 7

mature mRNA is read by ribosomes to synthesize proteins
tRNAs read the mRNA and transport appropriate AA to the ribosomes
ribosomes covalently link AA together
release factor terminates the process

Question 8

Ribosomes

Answer 8

translators
made of many proteins associated w 4 rRNAs

Question 9

structure of tRNA

Answer 9

cloverleaf secondary structure
AA attachment site
anticodon arm (pairs w corresponding mRNA sequence)

Question 10

degeneracy of code

Answer 10

more than one triplet encodes for the same amino acid
64 possible combos of 3 letter code

Question 11

one triplet=

Answer 11

one amino acid

Question 12

each triplet is called a

Answer 12

codon

Question 13

synonymous codons

Answer 13

codons that specify the same amino acid

Question 14

codons are found in…

Answer 14

mRNA

Question 15

anticodons are found in…

Answer 15

tRNA
are complimentary to codons

Question 16

genetic code is non-overlapping

Answer 16

3 nucleotide window
never shifts just by 1 nucleotide- only ever 3

Question 17

open reading frame

Answer 17

goes from start to stop codon

Question 18

start codon

Answer 18

AUG

Question 19

Stop codon

Answer 19

UAA, UAG, UGA

Question 20

3 types of RNA involved in translation

Answer 20

mRNA
tRNA
ribosomes (RNA and protein)

Question 21

translation is carried out by…

Answer 21

ribosomes

Question 22

polypeptide synthesis is carried out from…

Answer 22

N-terminus to C-terminus (5-3)

Question 23

Ribosomes have 3 sites

Answer 23

A- Aminoacyl site
P- peptidyl site
E- exit site

Question 24

Aminoacyl site

Answer 24

charged tRNA attaches

Question 25

peptidyl site

Answer 25

peptide bond forms

Question 26

Exit site

Answer 26

tRNA dissociates

Question 27

Translation initiation

Answer 27

small ribosomal subunit binds to mRNA
scans mRNA until it finds start codon
tRNA added to P site and the large ribosomal sub unit binds
translation elongation
- reduction of GTP-GDP is what allows this

Question 28

Translation termination

Answer 28

no tRNAs associated w stop odon
RF 1 attaches to A site at stop codon
RF3 complex w GTP binds to ribosome
GTP hydrolyzed into GDP and mRNA, tRNA, and RFs are released from ribosome