Gene Transcription & RNA modification 2

Question 1

Gene

Answer 1

A segment of DNA that is used to make a functional product either RNA molecules (rare) or proteins (common)

Question 2

Transcription

Answer 2

Process of synthesizing RNA from a DNA sequence

Question 3

Structural genes

Answer 3

Encode the amino acid sequence of a polypeptide

Question 4

When a _________ is transcribed the product it makes is mRNA (messenger RNA)

Answer 4

Structural genes

Question 5

Translation

Answer 5

The sequence of nucleotides within mRNA determines the sequence of amino acid in a polypeptide to make proteins & those proteins determine our traits & phenotype

Question 6

__________ states the usual flow of genetic material information is from DNA to mRNA to proteins

Answer 6

Central dogma

Question 7

Gene expression

Answer 7

Overall process to turn a gene on to produce a functional product such as proteins

Question 8

_________ genes goes through transcription & translation

Answer 8

Structural genes

Question 9

__________ require base sequences that perform functional roles

Answer 9

Gene expression

Question 10

What are the different sequences in DNA?

Answer 10

1. Regulatory sequence
2. Promoter
3. Terminator
4. Coding region

Question 11

Regulatory sequence

Answer 11

Site for the binding of regulatory proteins, the role of regulatory proteins is to influence the rate of transcription

Question 12

Promoter

Answer 12

Site for RNA polymerase signals the beginning of transcription

Question 13

Terminator

Answer 13

Signals the end of transcription

Question 14

What are the different sequences in mRNA?

Answer 14

1. Ribosome bind site
2. Start codon
3. Codons
4. Stop codon

Question 15

Ribosome binding site

Answer 15

Site for ribosome binding, translation begins near this site

Question 16

Start codon

Answer 16

Is ATG & it specifies the 1st amino acid in a polypeptide sequence

Question 17

What is the 1st amino acid produced in bacteria?

Answer 17

Formylmethionine

Question 18

What is the 1st amino acid produce in eukaryotes?

Answer 18

Methionine

Question 19

Codons

Answer 19

3 - nucleotides sequences within the mRNA that specifies a particular amino acid

Question 20

Stop codon

Answer 20

Specifies the end of polypeptide synthesis

Question 21

What are the 3 different stop codons?

Answer 21

TAA, TAG, or TGA

Question 22

_________ mRNA may be polycistronic

Answer 22

Bacterial mRNA

Question 23

Polycistronic

Answer 23

It encodes two or more polypeptides

Question 24

What are the 3 stages of transcription?

Answer 24

1. Initiation
2. Elongation
3. Termination

Question 25

Initiation

Answer 25

Starts when RNA polymerase binds to promoter

Question 26

Elongation

Answer 26

Synthesis of mRNA

Question 27

Termination

Answer 27

RNA polymerase stops transcription

Question 28

Describe the process in transcription

Answer 28

1. In initiation the promoter functions as a recognition site for transcription factors, where those transcription factors allow RNA polymerase to bind to the promoter & DNA is unwinded by DNA helicase to form a bubble known as a open complex 2. Elongation begins when RNA polymerase slides along the DNA in an open complex to synthesize mRNA 3. Termination occurs when a terminator is reached that causes RNA polymerase & mRNA to fall off the DNA

Question 29

________ genes are 90% of the genes

Answer 29

Structural genes

Question 30

Nonstructural genes

Answer 30

Lead to un-translated RNA

Question 31

What is Non-structural genes role in translation

Answer 31

1. Make rRNA | 2. Make tRNA

Question 32

What is non-structural gene role in gene expression?

Answer 32

1. Make miRNA

Question 33

What is non-structural genes role in mRNA processing?

Answer 33

1. Make snoRNA | 2. Make snRNA

Question 34

A ________ is a short sequence of DNA that is necessary to start transcription in bacteria

Answer 34

Promoter

Question 35

Transcriptional start site

Answer 35

Where the 1st base is used as a template for RNA transcription & is denoted as +1

Question 36

_______ is where RNA polymerase binds to & its before the copy region

Answer 36

Promoter

Question 37

What are the two sequences in the promoter region?

Answer 37

1. -35 sequence | 2. -10 sequence

Question 38

What is the -35 sequence?

Answer 38

5'- TTGACA-3'

Question 39

What is the -10 sequence?

Answer 39

The TATA box 5'-TATAAT-3'

Question 40

_______ promoter yields better transcription because RNA polymerase binds better

Answer 40

Stronger

Question 41

Bacterial transcription is started (initiated) when _________ binds to the promoter

Answer 41

RNA polymerase holoenzyme

Question 42

In bacteria a core has _________

Answer 42

5 Subunits

Question 43

When the sixth unit __________ associated with the core enzyme it creates a RNA polymerase holoenzyme

Answer 43

Sigma Factor

Question 44

What are the two subunits in RNA polymerase holoenzyme?

Answer 44

1. Core enzyme with 5 proteins | 2. Sigma Factor

Question 45

When the _____ & ______ join together it makes a complete holoenzyme

Answer 45

Sigma factor & core enzyme

Question 46

Once the _________ is assembled it binds loosely to the DNA & slides along the DNA looking for the promoter

Answer 46

Holoenzyme

Question 47

When the holoenzyme finds the promoter the _______ recognizes both the -35 & -10 sequences & binds tightly to them

Answer 47

Sigma Factor

Question 48

The process of bacterial transcription is initiated when _______ in holoenzyme binds to the promoter forming a closed complex (where DNA strand is still doubled stranded)

Answer 48

Sigma Factor

Question 49

For bacterial transcription to begin the DNA strand must unwind to form an open complex where it unwinds at the ___________ because its easier to break A-T bonds since it only has 2 hydrogen bonds

Answer 49

TATA box sequence

Question 50

After the breaking of A-T rich region a short mRNA strand is made in the open complex then the _______ is released from the core enzyme where the release of the _____ starts the transition to elongation stage of transcription

Answer 50

Sigma Factor

Question 51

________ made when the sigma factor is release & initiation stage ends

Answer 51

Nascent RNA