7.2 Transcription and Gene Expression

Question 1

what is transcription

Answer 1

the process of rewriting DNA to RNA

Question 2

what is one important function of a non-coding region?

Answer 2

act as promoters

Question 3

mRNA

Answer 3

Encodes amino acid sequence of a polypeptide

Question 4

tRNA

Answer 4

brings amino acids to the ribosome

Question 5

rRNA

Answer 5

with ribosomal proteins, makes up the ribosomes

Question 6

The process by which genetic information is transferred from DNA to RNA is called _________________

Answer 6

transcription

Question 7

During transcription, the synthesis of the mRNA strand proceeds in which direction?

Answer 7

5’ to 3’

Question 8

.

Answer 8

.

Question 9

In eukaryotic, where does transcription take place ___

Answer 9

in the nucleus

Question 10

in eukaryotes, precursor mRNA molecules are processed in the ___________

Answer 10

Nucleus

Question 11

THE POLY(A) tail of an mRNA __________________________________

Answer 11

keeps the coding sequences from being degraded.

Question 12

self-cleaving RNAs that function catalytically are called ______________

Answer 12

ribozymes

Question 13

a prokaryotic mRNA transcript is __________

Answer 13

translated as it is being transcribed

Question 14

which parts of a eukaryotic gene are transcribed?

Answer 14

Both exons and introns

Question 15

pre-mRNA transcript

Answer 15

When the entire gene is transcribed into mRNA

Question 16

RNA polymerase

Answer 16

Enzyme similar to DNA polymerase that binds to DNA and separates the DNA strands during transcription

Question 17

Transcription steps

Answer 17

initiation, elongation, termination

Question 18

initiation of transcription

Answer 18

RNA polymerase attaches to the promoter region on the DNA and begins to unzip the DNA into two strands.

Question 19

Exons

Answer 19

Coding segments of eukaryotic DNA.

Question 20

Introns

Answer 20

Noncoding segments of nucleic acid that lie between coding sequences.

Question 21

elongation (transcription)

Answer 21

RNA polymerase unzips the DNA and assembles RNA nucleotides using one strand of DNA as a template.

Question 22

termination of transcription

Answer 22

RNA polymerase reaches a terminator sequence (Stop codon) and detaches from the template

Question 23

spliceosome

Answer 23

A large complex made up of proteins and RNA molecules that splices RNA intron, releasing the intron.

Question 24

epigenome

Answer 24

The epigenome is a multitude of chemical compounds that can tell the genome what to do.

Question 25

TATA box

Answer 25

A TATA box is a DNA sequence that indicates where a genetic sequence can be read and decoded. It is a type of promoter sequence, which specifies to other molecules where transcription begins.

Question 26

histones

Answer 26

A histone is a protein that provides structural support to a chromosome.

Question 27

Epigenetic tags

Answer 27

Epigenetic tags regulate gene expression by acting as gatekeepers, blocking or allowing access to a gene’s ‘on’ switch. These chemical tags (such as methyl or acetyl groups) are added directly to DNA or onto histones

Question 28

5’

Answer 28

the end of the DNA or RNA strand

Question 29

3’

Answer 29

3’ carbon a hydroxyl (-OH) group. This asymmetry gives a DNA strand a “direction”.

Question 30

enhancers elements

Answer 30

Enhancers are DNA-regulatory elements that activate transcription of a gene or genes to higher levels than would be the case in their absence

Question 31

silencers elements

Answer 31

Silencers are regulatory DNA elements that reduce transcription from their target promoters; they are the repressive counterparts of enhancers.

Question 32

promoter-proximal elements

Answer 32

Any regulatory sequence in eukaryotic DNA that is located close to (within 200 base pairs) a promoter and binds a specific protein thereby modulating transcription

Question 33

DNA methylation

Answer 33

DNA methylation regulates gene expression by recruiting proteins involved in gene repression or by inhibiting the binding of transcription factor(s) to DNA