gene to protein

Question 1

What is the initiator codon for protein synthesis

Answer 1

AUG

Question 2

What is the terminator codon for protein synthesis

Answer 2

UGA, UAA, UAG

Question 3

What is a promoter

Answer 3

Start site for transcription

it is a DNA sequence that signals the initiation of RNA synthesis.

The promoter indicates the beginning of a gene

Question 4

What is the TATA box

Answer 4

a conserved sequence in eukaryotic promoters

Question 5

What are transcription factors:

Answer 5

proteins that assist RNA polymerase II with binding the promoter, which initiates the transcription process

Question 6

What is the transcription initiation complex

Answer 6

transcription factors and RNA polymerase II bound to a promoter

Question 7

What are spliceosomes

Answer 7

complexes of proteins and small nuclear ribonucleoproteins that recognize the splice sites on the pre-mRNA

Question 8

What is RNA splicing

Answer 8

removes the introns and joins exons, creating an mRNA molecule with a continous coding sequence

Question 8

What is RNA polymerase II

Answer 8

Mediates transcription of mRNA

Question 9

what is RNA polymerase I/III

Answer 9

transcribes other RNA not destined to become proteins

Question 10

what are the functions of the 5’ cap and poly-A tail

Answer 10

facilitate export of mRNA

protect mRNA from hydrolytic enzymes

help ribosomes attach to the 5’ end

Question 11

What are exons and introns

Answer 11

exons are coding sequences for mRNA, they are joined together, introns are noncoding sequences that are removed through splicing

Question 12

What is the template strand

Answer 12

it is one of the DNA strands that is used to produce a template for the RNA transcript which matches it with complementary base pairs

Question 13

What are codon specific functions

Answer 13

they are the mRNA base triplets that are read in the 5’ to 3’ direction,

each codon specific the amino acid to be placed at the corresponding position along a polypeptide

Question 14

What are the three stages of transcription

Answer 14

Initiation, Elongation, Termination

Question 15

What is the difference in eukarotes and bacteria in RNA polymerase binding

Answer 15

In bacteria the RNA pol binds directly to the promoter

In eukaryotes, transcription factors mediate the bindinf of RNA pol

Question 16

What is the initiation stage of Transcription

Answer 16

Promoter, transcription factors, and the transcription initiation complex

Question 17

One gene codes for

Answer 17

one “transcriptional unit” that can be spliced into different mRNAs or “one pre-mRNA”

Question 18

DNA inherited by organisms ______ results in specific traits _______

Answer 18

genotype

phenotype

Question 19

Whats the main difference between prokaryotic transcription and eukaryotic

Answer 19

in prokaryotes, mRNA produced by transcription is immediately translated without processing

in Eukaryotes, primary RNA transcripts are modified through RNA processing prior to translation

Question 20

What is the template strand

Answer 20

one of the DNA strands that provides a template for producing the RNA transcript

Question 21

what is the general definition of a codon

Answer 21

a block of 3 DNA nucleotides that correspond to an amino acid

Question 22

what is the promoter

Answer 22

it defines the start of a gene

Question 23

what are the the template strands

Answer 23

the strand read by RNA polymerase to make mRNA

Question 24

what is the terminator

Answer 24

it defines the end of a gene

Question 25

what does the TATA box do

Answer 25

it is recognized by RNA polymerase as the start site and which strand to use

Question 26

what are the transcription factors

Answer 26

proteins that assist RNA polymerase II
with binding the promoter, which initiates transcription in
eukaryotes (for mRNAs).

Question 27

what is the process that must occur before RNA pol II can do its job?

Answer 27

transcription factors must bind to DNA prior to RNA pol

then additional transcription factors bind to RNA pol to form the transcription initiation complex

Question 28

what is Transcription initiation complex

Answer 28

transcription factors and
RNA polymerase II bound to a promoter.

Question 29

in what direction does RNA pol II add nucleotides

Answer 29

5’-3’

Question 30

In bacteria, how does RNA pol II know how to stop?

Answer 30

It ends at the terminator sequence

Question 31

In eukaryotes, how does RNA pol II stop?

Answer 31

RNA pol II transcribes a polyA sequence (AAUAAA).

Then 10-35 nucleotides later, the proteins release the pre-mRNA

Question 32

Why is Eukaryotic transcription more complicated?

Answer 32

Due to chromatine packing

Question 33

How many RNA pol do Eukaryotes have?

Answer 33

3

RNA pol I: for transcription of mRNA

RNA I/II: for transcribing other RNA (not for proteins)

Question 34

Do Bacteria mRNA need to be spliced?

Answer 34

No, they do not have introns or exons

Question 35

How is RNA splicing carried out?

Answer 35

Through spliceosomes

Question 36

what are spliceosomes?

Answer 36

complexes of proteins + snRNPS (ribonucleoproteins) that recognize splice sites on pre-mRNA

Question 37

a single primary transcript can be spliced into _______

Answer 37

several different mRNAS

Question 38

Because of alternative splicing, the number of different
proteins an organism can produce is ______

Answer 38

much greater than its
number of genes.

Question 39

what is Alternate Splicing of Exons

Answer 39

Different forms of a protein
from the same gene
sequence.

Question 40

• RNA polymerase moves along the template strand from which direction?

Answer 40

3’-5’, it adds nucleotides to the 3’ OH end

Question 41

Alternative RNA Splicing:

Answer 41

Allows production of similar proteins from different primary RNAS