Unit 6.1-6.3

Question 1

Prokaryotic have

Answer 1

-Circular chromosomes
-no nucleus
-single loop of DNA

Question 2

Eukaryotic have

Answer 2

-multiple linear chromosomes
-a nucleus with DNA
-non looped chromosomes

Question 3

Plasmids

Answer 3

small extra chromosomal, double-stranded circular DNA molecules in prokaryotes and some eukaryotes

Question 4

Pyrimidines

Answer 4

single ringed bases
ex. cytosine, thymine and uracil

Question 5

Purines

Answer 5

double ringed bases
ex. Adenine and Guanine

Question 6

helicase

Answer 6

enzyme that untwists the double helix of DNA at replication forks separating the 2 strands and making them available as template strands

Question 7

topoisomerase

Answer 7

breaks, swivels, and a rejoins the parental DNA of the replication fork relieving the strain caused by unwinding

Question 8

DNA polymerase

Answer 8

enzyme that adds nucleotides to new strand, also cuts out primary and adds DNA

Question 9

semi conservative replication

Answer 9

new molecules built have one of the original and one new in a DNA structure

Question 10

leading strand

Answer 10

moves toward the 5’ end and replication fork
built continuously

Question 11

lagging strand

Answer 11

moves away from replication fork
built fragmented or discontinuously

Question 12

DNA Ligase

Answer 12

seals the free end of the new DNA to the old DNA, making the strand complete

Question 13

replication fork

Answer 13

religion on a replicating DNA molecule where the parental strands are being unwound and new strands are being synthesized

Question 14

the flow of genetic info goes:

Answer 14

DNA –> RNA –> Protein (only retroviruses don’t follow this)

Question 15

Proteins are the links between ____ and _____

Answer 15

genotype and phenotype

Question 16

transcription

Answer 16

-RNA polymerase attaches to promoter on the TATA box using transcription factors
-RNA polymerase reads the DNA and puts the corresponding nucleotide on the mRNA
-leaving you with a “complete” mRNA

Question 17

template strand can be known as

Answer 17

-non coding strand
-minus strand
-antisense strand

Question 18

transcription factors are

Answer 18

specific for every gene

Question 19

RNA polymerase always reads DNA from

Answer 19

the 3’ to 5’ so that the RNA is 5’ to 3’

Question 20

RNA processing only occurs in ___ and mRNA is ____ until after it undergoes processing

Answer 20

eukaryotic cells, NOT FUNCTIONAL

Question 21

What do introns do?

Answer 21

midigate mutations

Question 22

Alternative RNA splicing

Answer 22

cutting the pre-mRNA differently which creates different proteins from one gene (such as cutting out an exon)

Question 23

RNA processing

Answer 23

-cuts the introns out of the pre-mRNA leaving just the exons
-add on the 5’ cap and poly-A tail which keep it stable and make the mRNA reusable

Question 24

a ribosome is made up of

Answer 24

rRNA

Question 25

Translation

Answer 25

-tRNA brings in start codon to the ribosome into the P site starting the process
-tRNA brings in more amino acids building a polypeptide chain going from the p site to A site to combine with the new amino acids
-the tRNA bumps down a site each time till it gets to the e site where it gets pushed out the ribosome to go find a new amino acids
-this continues till a stop codon is reached and a release factor comes and breaks everything apart

Question 26

elongation

Answer 26

polypeptide chain goes from the P site to combine with the amino acid in the a site

Question 27

translocation

Answer 27

tRNA bumping down a site till it gets to e site and gets booted out the ribosome

Question 28

If the ribosome is on the endoplasmic reticulum what will be likely transported out of the cell

Answer 28

the protein

Question 29

reverse transcriptase

Answer 29

an enzyme encoded by certain viruses (retroviruses) that uses RNA as a template for DNA synthesis

Question 30

Why do RNA viruses change so much?

Answer 30

reverse transcriptase always makes a mistake an causes mutations