Molecular Structure of DNA & RNA

Question 1

Molecular Genetics

Answer 1

The study of DNA structure & its function at the molecular level

Question 2

What are the 4 criteria genetic material must meet?

Answer 2

1. Information
2. Transmission
3. Replication
4. Variation

Question 3

Information

Answer 3

Genetic material must contain the information necessary to construct an entire organism

Question 4

Transmission

Answer 4

During reproduction the genetic material must be passed from parents to offsprings

Question 5

Replication

Answer 5

Must be copied

Question 6

__________________ contain both DNA & Proteins

Answer 6

Chromosomes

Question 7

____________ experiments indicated that genetic material can transform pneumococus

Answer 7

Griffths

Question 8

Describe Griffth experiment

Answer 8

He had two strains: a R strain which had no capsule & a S strain which has a capsule

When he injected the live R strain into the mouse it lived but when he injected live S strain into the mouse it died (This showed that the capusle is protecting the S strain from antibodies to cause infection)

He then injected a heat killed S strain (dead S strain) & a live R strain into the mouse & it died

Question 9

What does the results of Griffths tell you?

Answer 9

Since when he adds the dead S strain & a Live R strain this shows us that the R strain took genetic material from the dead S strain & transformed into a S strain with its own capsule (process called transformation)

Question 10

Transformation

Answer 10

When a bacteria dies & transfers its genetic material to another bacteria slowly modifying that bacteria

Question 11

Avery, MacLead, & McCarthy showed that _______ is the substance that transforms bacteria to another bacteria

Answer 11

DNA

Question 12

Describe Avery, MacLead, & McCarthy experiment

Answer 12

They purified macromolecules (lipids, carbohydrates, proteins, & nucleic Acids (DNA & RNA))

They realized when an R strain had DNA of S strain then the R strain turned into an S strain (So DNA is the genetic material & not proteins)

Question 13

Hershey & Chase provided evidence that ______ is the genetic material of T2 phage (type of bacteriophage)

Answer 13

DNA

Question 14

Bacteriophage (phage)

Answer 14

A virus that infects bacteria cells (has only 2 macromolecules (DNA & proteins))

Question 15

Describe Hershey & Chase experiment

Answer 15

They labeled ³²P for DNA (beacuse DNA have alot of P) & ³⁵S for proteins

They grew infected cells in isotopes and a virus would either get ³²P or ³⁵S and they would inject new cells with one of the viruses

They realized that mostly DNA was inside the infected cell

Question 16

Nucleic Acids

Answer 16

DNA & RNA

Question 17

__________ & _________ are macromolecules & have 4 levels to their structure

Answer 17

DNA & RNA

Question 18

What are the 4 levels to DNA & RNA structure?

Answer 18

1. Has nucleotides
2. Nucleotides are linked together in a linear manner to form a strand of DNA or RNA
3. Two strands of DNA (sometimes RNA) interact with other to form a double helix
4. 3D structure of DNA is found within chromosomes

Question 19

_____________ is monomer made up of 3 things

Answer 19

Nucleotide

Question 20

What are the 3 things that nucleotides are made of?

Answer 20

1. Phosphate
2. Sugar
3. Base

Question 21

What are the types of sugar?

Answer 21

1. Dexoyribose (Found in DNA)
2. Ribose (Found in RNA)

Question 22

What are the two cateogories bases?

Answer 22

1. Purines Bases
2. Pyrimidine Bases

Question 23

Purines Bases

Answer 23

Adenine (A), Guanine (G) (Have a double ring structure)

Question 24

Pyrimidine Bases

Answer 24

Thymine (T), Cytosine (C), & Uracil (U) (Have a single ring structure)

Question 25

_____________ only found in DNA & _________ only found in RNA it replaces thyamine

Answer 25

Thyamine & Uracil

Question 26

Adenine, guanine, & cytosine found in both _______ & ________

Answer 26

DNA & RNA

Question 27

______________ bond links the nucleotides in DNA & RNA

Answer 27

Phosphodiester

Question 28

The __________ & _________ molecules form a “backbone” of the strand where it is negatively charged & the bases point inwards

Answer 28

Phosphate & Sugar

Question 29

DNA is directional “polarity” where it runs in the ____ to ____ direction for one strand & the other strand runs in the ____ to ____ direction

Answer 29

5’ to 3’ or 3’ to 5’

Question 30

Linus Pauling

Answer 30

Proposed DNA is in a helical strcuture

Question 31

Rosalind Franklin & Maurice Wilkins used __________ to try find the structure of DNA

Answer 31

X- ray diffraction

Question 32

_______________ found that DNA has a biochemical composition in which the amounts of adenine (A) & thyamine (T) are equal where they bind together & the amount of G & C are equal & they bind together

Answer 32

Charagaff

Question 33

A binds to T in a _______ ratio & G binds to C in a 1:1 ratio

Answer 33

1:1

Question 34

__________ & ___________ proposed the correct structure of DNA has a double helix

Answer 34

Watson & Crick

Question 35

Describe Watson & Crick model of DNA

Answer 35

Showed that DNA has 2 strands in a double helix where there are hydrogen bonds between the bases

The backbone of DNA was on the outside & the bases were on the inside (stack like plates)

The two backbone strands where antiparrel so one strand is in the 5’ to 3’ direction & the other strand is antiparrel & in the 3’ to 5’ direction (twist helix)

Question 36

A & T has ____ hydrogen bonds & G & C has _____ hydrogen bonds

Answer 36

2, 3