Exam 2

Question 1

Purine

Answer 1

Double ringed nucleotide

Question 2

Start codon

Answer 2

indicates where to initiate translation

Question 3

TRANS-ACTING ELEMENTS

Answer 3

protein that binds to cis-acting to control gene expression

Question 4

pyrimidine

Answer 4

single ringed nucleotide

Question 5

stop codon

Answer 5

indicates where to end translation

Question 6

cis-acting element

Answer 6

sequence of DNA that may enhance or silence DNA when acted upon

Question 7

Promoter

Answer 7

indicates where to initiate transcription

Question 8

sense codon

Answer 8

3 mRNA bases that code for an amino acid

Question 9

Protein-coding gene

Answer 9

encodes a polypeptide

Question 10

terminator

Answer 10

indicates where to end transcription

Question 11

DNA and RNA are _______

Answer 11

nucleic acids

Question 12

Ribosomes can be found in DNA

Question 13

What would the complementary strand to the following DNA strand?

5’ GCATAGGCC 3’

Answer 13

3’ CGTATCCGG 5’

Question 14

Eukaryotic organisms have circular DNA.

Answer 14

fasle

Question 15

Chromatin is made of

Answer 15

DNA and proteins (histones)

Question 16

What is the repeating structural unit in chromatin called?

Answer 16

nucleosome

Question 17

Heterochromatin is highly compact and transcriptionally inactive.

Answer 17

True

Question 18

What is the term for a segment of nucleotides in between the sections that actually code for something?

Answer 18

Introns

Question 19

Genome size does not equate to species complexity

Answer 19

true

Question 20

moderately and highly repetitive sections of DNA typically code for what?

Answer 20

Transposons

Question 21

DNA replication results in ________

Answer 21

Two daughter molecules identical to the parent molecule

Question 22

What enzyme bids Okazaki fragments

Answer 22

DNA ligase

Question 23

What enzyme prevents the parent strand from rebounding while the daughter strands are built?

Answer 23

Single-strand binding proteins

Question 24

What enzyme lays RNA primers before the addition of new nucleotides to daughter strands?

Answer 24

Primase

Question 25

What enzyme breaks hydrogen bonds between DNA strands in DNA replication

Answer 25

DNA helicase

Question 26

what is a major difference between the Holiday and Double-strand break model?

Answer 26

*The amount/ types of enzymes involved *The amount of strands initially broken to begin the process

Question 27

what protein complex is responsible for aiding in double-strand break model strand invasion?

Answer 27

RecA

Question 28

RNA polymerase II transcribes what?

Answer 28

mRNA

Question 29

Which enzyme plays a role in RNA modification?

Answer 29

Spliceosome

Question 30

Why are polyA tails important

Answer 30

*protects mRNA from shortening *helps mRNA exit the nucleus *regulates gene expression

Question 31

a protein can be made of one or many polypeptides

Answer 31

true

Question 32

amino acids are bound by what

Answer 32

peptide bonds

Question 33

What is the term for the characteristic of the genetic code having more than one codon specifying the same amino acid?

Answer 33

degeneracy

Question 34

If two codons code for the same amino acid, what are they?

Answer 34

synonymous codons

Question 35

Since there are 20 types of amino acids, how many types of aminoacyl-tRNA synthetase are there?

Answer 35

20

Question 36

all proteins will have a quaternary structure

Answer 36

false

Question 37

3 things a nucleotide is composed of

Answer 37

1. at least one phosphate group 2. a pentose sugar 3. a nitrogenous base

Question 38

what are the two suggestions for why transposition occurs

Answer 38

1) The selfish DNA hypothesis states that transposons proliferate without causing harm, so there is no reason for it to not happen. 2) The Exon shuffling hypothesis, which says this occurs because it offer some sort of advantage and broadens the gene pool.

Question 39

What concept/process do the Holliday model and double-strand break model attempt to explain?

Answer 39

The Holliday model and the double-strand break model attempt to explain Homologus recombination.

Question 40

What is the central dogma of genetics? Utilize the terms "collinearity" and "gene expression."

Answer 40

The central dogma of genetics is DNA to RNA to Proteins. During Collinearity the sequences in our genes dictates the amino acid sequences our bodies make. Gene expression takes the information from the amino acids and gives it a specific funtion.

Question 41

Describe what happens during each stage of Transcription: Initiation: Elongation: Termination:

Answer 41

Initiation: the intitial binding of RNA polymerase to the promoter in order to begin RNA synthesis. Elongation: the synthesis of RNA using DNA as a template Termination: release of the newly made RNA transcript and RNA polymearase from the DNA

Question 42

A. What role do ribosomes play in protein synthesis? B. What happens at the A, E, and P sites?

Answer 42

A. Ribosomes conatin discrete sites where tRNA binds and the poplypeptide is synthesized. B. Aminocyl (A site) - where a charged tRNA initially binds Peptidyl (P site) - carries a tRNA along with a polypeptide Exit (E site) - where an uncharged tRNA exits