Biology

Question 1

Alpha vs beta glycosidic linkages

Answer 1

Humans are able to digest alpha linkages
Alpha linkages: glycogen, starch
Beta linkages: Cellulose

Question 2

Terpenes

Answer 2

Made from isoprene units, functional group in wax, some vitamins, etc.

Question 3

Heterochromatin

Answer 3

Tightly wound DNA

Question 4

Euchromatin

Answer 4

Less tightly wound DNA, more transcriptional activity

Question 5

Exonuclease

Answer 5

Cuts off DNA at the end

Question 6

Endonuclease

Answer 6

Cleaves DNA in the middle

Question 7

Theta replication

Answer 7

prokaryotic circular chromosome replication, single ORI

Question 8

Missense mutation

Answer 8

one amino acid is replaced by another

Question 9

Nonsense mutation

Answer 9

Stop codon

Question 10

Haploinsufficiency

Answer 10

Diploid organism that has only one functional copy of a gene, and this isn’t enough for the organism to return to its normal state/phenotype

Question 11

Prokaryotic transcription promoter

Answer 11

Requires Pribnow box (-10 bp) and -35 sequence

Question 12

tRNA loading/amino acid activation

Answer 12

Amino acid binds to ATP to form aminoacyl AMP, leaving ppi -> 1Pi. Then aminoacyl AMP + tRNA -> A<P leaves to form aminoacyl-tRNA. Catalyzed by the enzyme aminoacyl-tRNA synthetase, which is amino acid specific.

Question 13

Shine-Delgarno sequence

Answer 13

prokaryotic -10bp ribosomal binding site

Question 14

DNA methylation

Answer 14

Blocks gene from transcriptional proteins, causes DNA to be more tightly wound around the histone

Question 15

Lac operon

Answer 15

Inducible, stimulated by an abundance of the substrate. Helps w lactose metabolism. When lactose is present, it will allosterically bind to the repressor protein, causing it to fall off the operator and to allow for transcription.

Question 16

Trp operon

Answer 16

Repressible operon that synthesizes Trp. Trp repressor is usually off of the operator. When there is more Trp, the cell does not need to make more, so Trp will bind to the repressor and bind to the operator.

Question 17

Difference bw three types of RNA polymerase?

Answer 17

I: transcribes rRNA
II: mRNA
III: tRNA

Question 18

snRNA

Answer 18

spliceosome

Question 19

miRNA/siRNA

Answer 19

RNA interference, post-transcriptional modifications

Question 20

piRNA

Answer 20

PIWI-interacting RNA, prevents transposons from mobilizing