C8 Control of Gene Expression

Question 1

Most important level of gene control

Answer 1

transcription

Question 2

? bind to DNA to switch genes on and off

Answer 2

gene regulatory proteins

Question 3

Many Gene regulatory proteins use ? to make specific contact with DNA

Answer 3

motifs

Question 4

related genes close together in bacteria

Answer 4

operons

Question 5

CAP is active when cAMP levels are high and acts to ? transcription

Answer 5

promote

Question 6

The lactose operon is transcribed when ? is present and ? is absent

Answer 6

lactose is present and glucose is absent

Question 7

RNAP I makes

Answer 7

rRNA

Question 8

RNAP II makes

Answer 8

mRNA and snRNA

Question 9

RNAP III makes

Answer 9

tRNA

Question 10

Bacterial RNAPs use ? to recognize promoters

Answer 10

sigma factors

Question 11

Eukaryotic RNAPs use ? to recognize promoters

Answer 11

General Transcripton factors

Question 12

Some transcription factors are ? that reduce the positive charge on histones within the nucleosomes and loosen their grip on DNA

Answer 12

histone acetylases

Question 13

riboswitch

Answer 13

RNA that can control its own transcription by inducing a conformation change

Question 14

Binds to the trp operator to control tryptophan gene transcription

Answer 14

trp repressor

Question 15

Helps RNAP bind to weak promoter sequences

Answer 15

CAP activator

Question 16

substrate that turns on CAP activator

Answer 16

cAMP

Question 17

Expression of ?, a transcription factor, in a skin cell converts the cell to a muscle cell

Answer 17

myoD

Question 18

Ways gene expression can be transmitted to daughter cells

Answer 18

positive feedback loop, DNA methylation, condensed chromatin structure

Question 19

positive feedback loop

Answer 19

key transcription regulator activates transcription of its own gene

Question 20

DNA methlation has this generally turns off genes by…

Answer 20

attracting proteins that block expression

Question 21

Regulation of translation initiation (4)

Answer 21

Riboswitch, repressor/activator, thermosensor, antisense RNA

Question 22

micro RNAs (miRNAs) control at least ? of all protein coding genes

Answer 22

1/3

Question 23

Humans produce more than ? different miRNAs

Answer 23

400

Question 24

miRNA function

Answer 24

Assemble with proteins to form RISC which patrols cytoplasm looking for complementary RNA sequences to destroy

Question 25

RISC stands for

Answer 25

RNA induced silencing complex

Question 26

Describe RNA interference

Answer 26

double stranded RNA is introduced. broken down into fragments by DICER nuclease. Fragments called siRNAs. siRNAs combine with proteins to form RISCs

Question 27

many activators summon ? which attaches an acetyl groups to histones

Answer 27

histone acetylases

Question 28

combinatorial control

Answer 28

eukaryotic genes are controlled by combinations of regulatory proteins