test 6

Question 1

DNA methylation

Answer 1

the addition of methyl groups to dna (often at cytosine bases) which typically suppresses gene expression by preventing transrciption factors from binding.

Question 2

Histone acetylation

Answer 2

the addition of histone to acetyl proteins loosening the dna wrapped around them and allowing genes to be more easily transcribed

Question 3

Enhancers

Answer 3

Dna sequences that increase the rate of transcription when specific proteins (activators) bind to them, even if they are far from the gene

Question 4

Repressor Proteins

Answer 4

Proteins that bind to specific DNA sequences (like silencers or operators) and block transcriptionn by preventing RNA polymerase from binding

Question 5

Transcription Factors

Answer 5

Proteins that help regulate gene expression by binding to specifc DNA sequences and assisiting ot blocking RNA polymerase

Question 6

Master genes

Answer 6

Genes that control the expression of many other genes and direct large developmental processes like body plan formation

Question 7

RNAi

Answer 7

A process where small RNA molecules (like siRNA or miRNA) bind to mRNA and either block translation or cause the mRNA to be destrpyed reducing gene expression.

Question 8

5’ Cap

Answer 8

A modified guanine nucleotide added to 5’ end of the mRNA for protection and ribosome binding

Question 9

Alternative Splicing

Answer 9

A process during mRNA editing where different exons are combined various ways to produce multiple proteins from one gene

Question 10

Cell Differentiation

Answer 10

The process where unspecialized cells (like stem cells) become specialized in structure and function through gene regulation

Question 11

Universal Genetic Code

Answer 11

the nearly identical way that codons (triplets of RNA bases) specify amino acids in all living organisms - evidence of a common ancestor

Question 12

Stickleback Gene regulation

Answer 12

In stickleback fish, chnages in gene regulation (like turning off pelvic genes via switches) show how evolution can act on DNA control elements not just genes themselves

Question 13

Gel Electrophoresis

Answer 13

A technique to separatte DNA fragments by size. DNA is loaded into gel and pulled throuogh by an electric current; smaller fragments move faster

Question 14

Restriction Enzymes

Answer 14

Proteins that cut DNA at a specific sequences often used to prepare DNA for gel electrophores or to clone genes

Question 15

PCR ( Polymerase Chain Reaction )

Answer 15

A method to amplify (make many copies of) specific DNA segments using heat cycles and enzymes, often used before gle electrophoresis