Unit 6b - Gene to Protein

Question 1

Central Dogma

Answer 1

dna –> mrna –> protein

Question 2

Transcription

Answer 2

dna => m-rna

Question 3

Translation

Answer 3

rna => protein

Question 4

One gene =

Answer 4

one rna molecule

Question 5

DNA properties

Answer 5

nucleic acid composed of nucleotides
double stranded
deoxyribose
thymine
template for individual

Question 6

RNA properties

Answer 6

nucleic acid composed of nucleotides
single stranded
ribose
uracil
many different roles

Question 7

Pre-mRNA

Answer 7

precursor to mRNA , newly transcribed and not edited

Question 8

mRNA

Answer 8

carries the code from dna to ribosome, for a specific amino acid

Question 9

tRNA

Answer 9

carries a specific amino acid to ribosome based on its anticodon to mRNA codone
transcribed in the nucleus

Question 10

Codon

Answer 10

A sequence of three consecutive nucleotides in a DNA or RNA molecule that codes for a specific amino acid.

Question 11

rRNA

Answer 11

makes 60% of the ribosome; site of protein synthesis

Question 12

RNAi

Answer 12

interfernce RNA; regulatory molecule

Question 13

Ribozyme

Answer 13

RNA molecule that functions as an enzyme

Question 14

Each gene , one DNA strand is the

Answer 14

template strand

Question 15

mRNA complementary to template
—> what direction does mRNA function.

Answer 15

5’ => 3’

Question 16

What codes for amino acids in polypeptide chain?

Answer 16

mRNA triplets (codons)

Question 17

How many different codon combinations?

Answer 17

64

Question 18

Redundancy

Answer 18

1+ codons code for each 20 amino acids

Question 19

Reading frame

Answer 19

groups of 4; one of three possible ways of reading a nucleotide sequence

Question 20

RNA polymerase

Answer 20

separates dna and transcribes mRNA

Question 21

mRNA elongates

Answer 21

in 5’ => 3’ direction

Question 22

Uracil replaces

Answer 22

thymine

Question 23

RNA polymerase attaches to ..

Answer 23

a promoter and stops at a terminator

Question 24

Initation of Transcription in Bacteria?

Answer 24

rna polymerase binds directly to promoter

Question 25

TATA box

Answer 25

dna sequence (TATAAAA) upstream from promoter.

Question 26

Transcription Factors

Answer 26

must recognize TATA box before RNA polymerase can bind to a DNA promoter

Question 27

RNA polymerase in elongation ....

Answer 27

adds RNA nucleotides to the 3' end of the growing chain.

Question 28

As RNA polymerase moves

Answer 28

it untwists DNA, then rewinds it transcribes mRNA

Question 29

In termination RNA polymerase transcribes

Answer 29

a terminator sequence in DNA

Question 30

What are Pre-mRNA additions

Answer 30

5' cap and 3' poly-A tail are added.

Question 31

Splicing

Answer 31

introns cut out , exons joined together.

Question 32

Ribosome

Answer 32

rRNA + proteins

Question 33

Active site A

Answer 33

holds AA to be added

Question 34

Active site P

Answer 34

holds growing polypeptide chain

Question 35

Active site E

Answer 35

exit site for tRNA

Question 36

Ribosomes Initiation

Answer 36

small subunits binds to start codon on mRNA tRNA carrying Met attaches to P site

Question 37

Ribosome Elongation: Codon Recognition

Answer 37

tRNA anticodon matches codon in A site

Question 38

Ribosome Elongation: Peptide Bond Formation

Answer 38

AAs in A site forms peptide bond in P site

Question 39

Ribosome Elongation: Translocation

Answer 39

tRNA in A site moves to P site ; tRNA in P site moves to E site (then exits)

Question 40

Ribosome Termination: Stop Codon

Answer 40

reached and translation stops (UAG.UAA , and UGA)

Question 41

Ribosome Termination: Release Factor

Answer 41

binds to stop codon; polypeptide is released --> ribosomal subunits dissociate (break apart)

Question 42

Prokaryotes

Answer 42

Central dogma in cytoplasm DNA/RNA in cytoplasm RNA poly binds directly to promoter Transcritption makes mRNA No introns

Question 43

Eukaryotes

Answer 43

Transcription in nucleus ---> Translation in cytoplasm DNA in nucleus ; RNA travels in/out of nucleus RNA poly binds to TATA box and transcription begins At end of transcription = pre-RNA --> RNA processing --> final mRNA Exons and introns