DNA

Question 1

Griffith worked with how many different stains of pneumonia and he used how many groups?

Answer 1

2 strains of pneumonia; 4 distinct groups in his test

Question 2

4 groups of Griffith's experiment:
(S) or (R)?
And the mice?
Group A:
Group B:
Group C: 
Group D:

Answer 2

A: Disease-causing (S) strain - the mouse died :-(
B: Non-disease causing (R) strain - the mouse lived :-)
C: Heat-killed S strain - the mouse lived :-)
D: Heat-killed S strain + R strain - the mouse died :-(

Question 3

Griffith’s experiment showed what about the strains, in which group?

Answer 3

something passed between the R & S strains in Group D - a transforming agent

Question 4

He followed up these results by doing what? And what happened to the mice in group D ?

Answer 4

He followed up by treating bacteria to destroy lipids, carbohydrates, proteins . . .Group D still died

Question 5

This result led to the discovery of

Answer 5

nucleic acids.

Question 6

DNA
Deoxyribonucleic Acid

Function:

Answer 6

• function is to store & transmit genetic information between generations

Question 7

Chromosomes are made up of tightly wound what?

This term is DNA wrapped around what? called?

Answer 7

• chromosomes are made up of chromatin

* chromatin is DNA wrapped around proteins called histones

Question 8

The Building Blocks - Nucleotides are Made of: (list 3)

Answer 8

Made of:

• 5-C Sugar (Deoxyribose for DNA)
• Phosphate Group
• Nitrogenous Base - determines nucleotide

Question 9

What are nucleotides made up of?
(list 4)
A…, C…, G…, T….

Answer 9

4 nucleotides for DNA:

• Adenine (A)
• Cytosine (C)
• Guanine (G)
• Thymine (T)

Question 10

How do the nucleotides go together?

Answer 10

A <> T

C <> G

Question 11

The shape of DNA

Answer 11

• double helix

* discovered by Watson & Crick . . . with help.

Question 12

How does it all go together?
rails:
rungs:
Directionality:
   top rail - 
   bottom rail -

Answer 12

• rails are made up of alternating phosphates and sugars
• rungs are made up of nitrogenous bases bound by hydrogen bonds
• Directionality –
  top rail 5’ to 3’,
  bottom rail 3’ to 5’

Question 13

DNA Replication
the cell does what?
replications> is called semi-what?
templates from are what strands?

Answer 13

• cell divides
• the DNA replicates - it’s semi-conservative with the parental strands serving as templates
• there are 3 steps

Question 14

Step 1 - Unwinding

• Which DNA (enzyme) unwinds & unzips the DNA strand?
• What keeps the strands apart?

Answer 14

• DNA helicase (enzyme) unwinds & unzips the DNA strand

* Proteins are used to keep strands apart

Question 15

Step 2 - Base Pairing
What DNA (enzyme) brings in complementary nucleo-tides to each strand?
* What DNA enzyme reads 3’ to 5’ and builds 5’ to 3’
~ One strand is what?
~ The other strand is in chunks called what?

Answer 15

• DNA Polymerase (enzyme) brings in complementary nucleotides to each strand
• DNA Polymerase reads 3’ to 5’ and builds 5’ to 3’
  ~ One strand continuous
  ~ Other strand in ‘chunks’—Okazaki Fragments—glued together by DNA Ligase (enzyme)

Question 16

Step 3 - Joining
* Replication takes place along on point or numerous
points on the strand? - What are these points called?
* Enzyme proof-reads the final how many strands to ensure they that they are what?

Answer 16

• Replication takes place along NUMEROUS
  points on the strand - Replication ‘forks’ or ‘bubbles’
• When these ‘bubbles’ reach each other, the strands are connected
• Enzyme proof-reads the final two strands to ensure they are paired correctly.

Question 17

The Daughter Strand (copy:)

Answer 17

• half of it will be new.

* half of it will be the original parent strand

Question 18

DNA
Deoxyribonucleic Acid

Storage in prokaryotes:
Storage in eukaryotes:

Answer 18

• storage -
  in prokaryotes it’s in a ring of DNA in the cytoplasm
  in eukaryotes it’s in chromosomes in the nucleus