18 - Gene regulation

Question 1

Differential gene expression

Answer 1

the expression of different genes by cells with the same genome

Question 2

Histone acetylation

Answer 2

the addition of an acetyl group to an amino acid in a histone tail

Question 3

DNA methylation

Answer 3

is a biological process where a small chemical group called a methyl group is added to the DNA molecule

Question 4

Epigenetic inheritance

Answer 4

refers to the transmission of information from one generation to the next that affects gene expression without changing the underlying DNA sequence.

Question 5

Enhancer

Answer 5

a segment of eukaryotic DNA containing multiple control elements, usually located far from the gene whose transcription it regulates

Question 6

Promoter

Answer 6

a specific nucleotide sequence in the DNA of a gene that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place

Question 7

Terminator

Answer 7

in bacteria, a sequence of nucleotides in DNA that marks the end of a gene and signals RNA polymerase to release the newly made RNA molecule and detach from the DNA

Question 8

Proximal control elements

Answer 8

are DNA sequences located NEAR a gene that help regulate the gene’s activity.

Question 9

distal control elements

Answer 9

are DNA sequences that regulate gene expression FROM A DISTANCE, sometimes thousands of base pairs AWAY from the gene they influence

Question 10

Activators

Answer 10

a protein that binds to DNA and stimulates gene transcription. In prokaryotes, activators bind in or near the promoter; in eukaryotes, activators generally bind to control elements in enhancers

Question 11

Transcription factors

Answer 11

a regulatory PROTEIN that binds to DNA and affects transcription of specific genes

Question 12

DNA-bending protein

Answer 12

is a type of protein that binds to DNA and causes it to bend or loop. This bending can bring distant parts of the DNA closer together, which is important for regulating gene expression

Question 13

RNA polymerase 2

Answer 13

is an ENZYME in eukaryotic cells that plays a crucial role in transcribing DNA into messenger RNA (mRNA).

Question 14

Repressors

Answer 14

a PROTEIN that inhibits gene transcription. In prokaryotes, repressors bind to the DNA in or near the promoter. In eukaryotes, repressors may bind to control elements within enhancers, to activators, or to other proteins in a way that blocks activators from binding to DNA.

Question 15

Alternative RNA splicing

Answer 15

is a process in eukaryotic cells that allows a single gene to produce multiple different proteins

Question 16

Exon

Answer 16

a sequence within a primary transcript that REMAINS in the RNA after RNA processing; also refers to the region of DNA from which this sequence was transcribed.

Question 17

Intron

Answer 17

a noncoding, intervening sequence within a primary transcript that is REMOVED from the transcript during RNA processing; also refers to the region of DNA from which this sequence was transcribed

Question 18

microRNA

Answer 18

a small, single-stranded RNA molecule, generated from a double-stranded RNA precursor. The miRNA associates with one or more proteins in a complex that can degrade or prevent translation of an mRNA with a complementary sequence.

Question 19

Ubiquitin

Answer 19

is a small REGULATORY PROTEIN found in almost all eukaryotic cells. Its primary role is to tag other proteins for degradation

Question 20

Proteasome

Answer 20

is a complex structure in cells that functions like a RECYCLING CENTER for proteins. It breaks down proteins that are damaged, misfolded, or no longer needed into smaller pieces called peptides