1.4

Question 1

RNA polymerase

Answer 1

enzyme that builds polymers of RNA

always adds new nucleotides to the 3’ end of the growing mRNA

Question 2

where does RNA polymerase attach to a gene to initiate transcription?

Answer 2

the promoter

Question 3

promoter

Answer 3

a region of DNA upstream of a gene where relevant proteins (such as RNA polymerase and transcription factors) bind to initiate transcription of that gene

Question 4

which of the two strands of DNA is used in transcription?

Answer 4

noncoding/template strand

Question 5

how does RNA polymerase know when to stop transcribing on the template strand?

Answer 5

transcription proceeds through terminator sequence, causing RNA polymerase to detach from DNA and release the transcript

Question 6

parts of transcription

Answer 6

initiation
elongation
termination

Question 7

what is the TATA box?

Answer 7

a DNA sequence

type of promoter sequence

able to define the direction of transcription and also indicates the DNA strand to be read. Proteins called transcription factors can bind to the TATA box and recruit an enzyme called RNA polymerase, which synthesizes RNA from DNA.

Question 8

transcription factors

Answer 8

proteins involved in the process of converting, or transcribing, DNA into RNA. Transcription factors include a wide number of proteins, excluding RNA polymerase, that initiate and regulate the transcription of genes.

Question 9

differential gene expression

Answer 9

the expression of different sets of genes by cells with the same gene

Question 10

control elements (sometimes known as gene switches)

Answer 10

generic term for a region of dna, such as a promoter or enhancer adjacent to (or within) a gene that allows the regulation of gene Expression by the binding of transcription factors.

can be found before the promotor and serve as binding site for transcription factors that regulate transcription

are non-coding DNA - the serve as binding sites for transcription factors that regulate transcription

Question 11

“general transcription factor”

Answer 11

transcription factors that act at the promoter of all genes

Question 12

what is needed to regulate expressions for genes that are not transcribed/expressed all the time?

Answer 12

transcriptional activators or enhancers

Question 13

proximal

Answer 13

located near the promoter

Question 14

distal

Answer 14

located farther away from the promoter

Question 15

when activators are bound to enhancers, transcription is…

Answer 15

on

Question 16

some control elements bind to transcription factors called repressors, what affect would repressor binding have in transcription?

Answer 16

it would prevent transcription from happening by binding to control element DNA or interfere with activators

Question 17

enhancer

Answer 17

short (50–1500 bp) region of DNA that can be bound by proteins (activators) to increase the likelihood that transcription of a particular gene will occur

ea enhancer is composed of about 10 control elements

it is the particular combination of control elements in an enhancer associated with a gene (rather than a unique control element) that is important in regulating a gene

Question 18

point mutation

Answer 18

a change in a single nucleotide pair of a gene

Question 19

nucleotide pair substitution mutation types

Answer 19

silent
missense
nonsense

Question 20

silent mutation

Answer 20

substitution

no effect on amino acid sequence

Question 21

missense mutation

Answer 21

substitution

range of affects depending on location and identity

Question 22

nonsense mutation

Answer 22

substitution

affect depend on the location of the new stop codon

Question 23

nucleotide-pair insertion/deletion mutation

Answer 23

frameshift - causing immediate nonsense or extensive missense

usually cause protein to be nonfunctional