DNA 1

Question 1

5 important features of DNA structure

Answer 1

double stranded. antiparallel. complementary. helical. stabilized non covalently so can be wound and unwound.

Question 2

in order to fit inside the cell: DNA is packed as? which is?

Answer 2

chromatin: supercoiled complex with proteins (histones)

Question 3

DNA function requires?

Answer 3

protein binding

Question 4

transcription: what, done by what, and in what direction

Answer 4

RNA polymerase synthesizing mRNA from template strand, new strand synthesized 5’ to 3’

Question 5

RNA synthesis begins where?

Answer 5

promoters: upstream of gene

Question 6

mutation: what? 3 types?

Answer 6

change in base sequence of DNA. missense. non sense (change to stop). frame shift (change reading frame)

Question 7

dravet syndrome

Answer 7

severe myoclonic epilepsy of infancy: caused by missense or nonsense mutation in sodium ion channel

Question 8

3 types of genes classified by expression rates

Answer 8

constitutive genes: always expressed. tissue specific genes like glucagon receptor. inducible genes like BOX or FAS enzymes.

Question 9

most important regulation of transcription

Answer 9

controlling the initiation of transcription by RNApolymerase

Question 10

in eukaryotes, gene expression regulation is ___

Answer 10

positive aka normal = no expression and you need TFs for transcription

Question 11

hetero vs. euchromatin

Answer 11

hetero = condensed, methylated DNA, deactylated histones = inactive. euchromatin = loose = histone acetylated, DNA not methylated = transcribed

Question 12

acetylation vs. methylation and transcriptional regulation

Answer 12

acetylation reduces histone affinity for DNA. histone groups acetylated and DNAnot methylated = active