DNA/RNA

Question 1

What were the results for the mice injections in the Griffith Experiment?

Answer 1

live pathogenic strain=mice die
live nonpathogenic strain (no protein coat)=mice live
heat-killed pathogenic strain=mice live
mix of heat-killed pathogenic and nonpathogenic strains=mice died

Question 2

What is transformation?

Answer 2

the transfer of genetic material from one cell to another which can alter the genetic makeup of the recipient cell

Question 3

What is a bacteriophage?

Answer 3

a virus that attacks bacteria

Question 4

What is a purine?

Answer 4

a base-double carbon ring. Adenine and Guanine

Question 5

What is pyrimidine?

Answer 5

base-single carbon ring. Cytosine, thymine (uracil in RNA)

Question 6

phosphodiester bond

Answer 6

holds sugars to phosphates on the sides of the DNA (RNA)

Question 7

hydrogen bond

Answer 7

holds the bases together to make the “rings” of the DNA ladder

Question 8

Chargaff’s Rule

Answer 8

A’s pair with T’s; G pairs with C’s
There is always an equal portion of A’s to T’s and of G’s to C’s. A:T and G:C
The base pairing is also known as being complementary

Question 9

semiconservative replication

Answer 9

the way DNA actually copies itself. copying genetic information is complementary
DNA unzips- one side serves as the template for the new strand being built

Question 10

Conservative Replication

Answer 10

parent DNA stays intact and makes new copies of DNA

Question 11

Dispersive Replication

Answer 11

parent DNA is dispersed throughout new DNA so each strand is a mix of old and new

Question 12

What are the three things that replication requires?

Answer 12

something to copy-parental DNA molecules serve as a template
something to do the copying-enzymes
building blocks-nucleotides

Question 13

Where does replication begin?

Answer 13

replication forks

Question 14

What enzyme glues new nucleotides to the growing strands

Answer 14

DNA polmerase 3

Question 15

What is the RNA primer

Answer 15

the anchor. the enzyme RNA primase builds a piece of RNA primer about 10 RNA nucleotides long. DNA Polymerase 3 recognizes the primer and starts to build new DNA strand

Question 16

leading strand

Answer 16

the DNA strand elongating toward the replication fork

Question 17

continuous replication

Answer 17

new DNA is built continuously by simply adding nucleotides to the 3 end

Question 18

lagging strand

Answer 18

the DNA strand elongating away from the replication fork

Question 19

discontinuous replication

Answer 19

new DNA is built in pieces

Question 20

Okazaki Fragments

Answer 20

segments of DNA about 100-20 nucleotides long

Question 21

What unwinds the DNA

Answer 21

helicase

Question 22

how are DNA strands kept open?

Answer 22

single-strand binding proteins

Question 23

DNA polymerase 1

Answer 23

removes primers and fills in gaps between Okazaki fragments

Question 24

DNA Ligase

Answer 24

rejoins the parent strand

Question 25

DNA Gyrase

Answer 25

releases tension in the DNA

Question 26

Primosome

Answer 26

composed of primase and helicase and accessory proteins

Question 27

Describe the Griffith Experiment

Answer 27

Griffith was trying to make a vaccine against the flu which was thought at the time to be caused by a bacterium called Streptococcus pneumoniae
The bacteria comes in two forms:
virulent (disease causing), makes deadly polysaccharide coat that causes blood poisoning
-“S” form
nonvirulent- no polysaccharide coat
-“R” form (shouldn’t kill)