Chapater 6.1 and 6.2

Question 1

Friedrich Miescher

Answer 1

Found phosphorus-rich material from nuclei of human white blood cells and named it nuclein (major component DNA)

Question 2

DNA 3 main characteristics

Answer 2

1. Made of sugar deoxyribose
2. Found mainly in cell nuclei
3. Acidic

Question 3

DNA

Answer 3

the molecule of heredity that encodes genetic information

Question 4

How is deoxyribose different than ribose?

Answer 4

2’ carbon has a hydrogen rather than a OH (hydroxyl) group

Question 5

Nucleotide

Answer 5

sub unit of DNA and RNA consisitng of nitrogenous base (A,G,T,C, or U), phosphate group and a sugar (deoxy or ribose)

Question 6

Bonds joining one nucleotide to another (form backbone of DNA)

Answer 6

covalent phosphodiester bonds

Question 7

Polymer

Answer 7

linked chain or repeating subunits that form a molecule

Question 8

What was believed to serve as genetic material before DNA

Answer 8

Proteins

Question 9

Why did they believe proteins over DNA

Answer 9

proteins are built of 20 different amino acids while DNA has 4; assumed DNA was too simple to contain complexity of genes

Question 10

With bacteria only having one circle chromosome, how do they divide?

Answer 10

binary fussion

Question 11

Prerequisite of genetic studies

Answer 11

detection of alternative forms of a trait among individuals of a population

Question 12

Frederick Griffith

Answer 12

Study Strep. pneumonia, in two bacteria forms smooth (S)(wild-type) and rough (R)(mutation)

Question 13

S bacteria appear smooth because

Answer 13

synthesize a polysaccharide capsule surround the cell
Virulent and kill most lab animails exposed to it

Question 14

R bacteria

Answer 14

lack enzyme to make polysaccharide

Question 15

Polysaccharide capsule function

Answer 15

protect the bacteria from an animal’s immune system

Question 16

Griffith’s finding

Answer 16

In 1928, genetic info from dead bacterial cells could be transmitted to live cels (live R forms + heat-killed S forms)
(Transformation)

Question 17

Transformation

Answer 17

ability of a substance to change the genetic characteristics of an organism

Question 18

Transformation mechanism

Answer 18

bacteria transfer genes from one strain to another
occurs when DNA from a donor is added to the bacterial growth medium and then taken up from the medium by the recipient

Question 19

Oswald T. Avery

Answer 19

In 1931, achieved transformation without using any animals, by growing R-form bacteria in medium in the presence of components from dead S forms

Question 20

Oswald T. Avery goal

Answer 20

Find the transforming principle (identify heritable substance in bacterial extract that induces transformation of R to S)

Question 21

Oswald T. Avery, Colin MacLeod, and Maclyn McCarty (1944)

Answer 21

treatment of purified DNA with a DNA-degrading enzyme destroying ability to cause mutation (DNA was the principle)

Question 22

Alfred Hershey and Martha Chase (1939)

Answer 22

Inflected bacterial cells with viruses; phages

Question 23

Bacteriophages (phages)

Answer 23

a virus for which the natural host is a bacterial cell
Bacteria eaters

Question 24

Life cycle phages

Answer 24

Inflect a bacterial cell; after 30 minutes cell bursts and hundred of newly made phages spill out

Question 25

Phage particle consist of

Answer 25

DNA contained within a protein coat

Question 26

Phage ghost

Answer 26

viral shell that remains attached to outer surface of bacterial cell wall by tiny syringes that bind and inject material into host

Question 27

Waring Blender Experiment (Hershey and Chase)

Answer 27

Grew two separate sets of phage *T2* in bacteria in two different culture media (one infused with radioactively 32P and the other with 35S). This would label proteins grown S and DNA in P (Mark each material when the phage inflect fresh bacterial cells) and used Waring blender to disrupt each one

Question 28

32P

Answer 28

radioactive phosphorus

Question 29

35S

Answer 29

radioactive sulfur

Question 30

Proteins incorporate

Answer 30

sulfur

Question 31

DNA contains

Answer 31

phosphorus but no sulfur

Question 32

Waring blender purpose

Answer 32

separating viral ghosts from bacteria harboring viral genes

Question 33

35S (in protein) remained in

Answer 33

supernatant solution

Question 34

Hershey-Chase experiment showed

Answer 34

Extracellular ghost were mostly protein while phage genes are made of DNA

Question 35

Which experiment had the greatest impact on DNA findings?

Answer 35

Hershey-Chase

Question 36

Diffraction pattern

Answer 36

reflect the helical structure of DNA

Question 37

What links the nucleotide in DNA chain

Answer 37

phosphodiester bond

Question 38

1-9

Answer 38

purines

Question 39

1-6

Answer 39

pyrimidines

Question 40

Purines

Answer 40

A and G

Question 41

pyrimidines

Answer 41

C, T, and U

Question 42

Nitrgogen base attached to

Answer 42

covalent attached to 1' carbon of deaoxyribose

Question 43

Nitrogen base + Sugar

Answer 43

Nucleoside

Question 44

Phosphate group attached to

Answer 44

5' carbon of sugar

Question 45

polarity

Answer 45

overall direction property of having distinct ends

Question 46

Phosphodiester bonds form link between

Answer 46

3' carbon of on nucleotide and t' carbon of the other

Question 47

Two ends of a single chain are

Answer 47

chemically distinct

Question 48

5' end

Answer 48

the first nucleotide

Question 49

Watson and Crick (1953)

Answer 49

discovered the structure of the DNA molecule DNA double helix

Question 50

Rosalind Franklin and Maurice Wilkins

Answer 50

X-ray images that showed that the molecule is spiral-shaped or helical

Question 51

Spacing between repeating units along axis of helix is

Answer 51

3.4 A

Question 52

1.0 A in meters

Answer 52

1.0 * 10^(-10) meters

Question 53

DNA helix completes one turn every

Answer 53

34 A

Question 54

Diameter of DNA molecule

Answer 54

20 A

Question 55

Single nucleotide diameter

Answer 55

10 A

Question 56

Erwin Chargaff showed

Answer 56

ratios of A-T and G-C had a 1:1 ratio

Question 57

Hydrogen bonds

Answer 57

weak electrostatic bonds that link pyrimidines and purines together

Question 58

A and T hydrogen bonds

Answer 58

2 bonds

Question 59

G and C hydrogen bonds

Answer 59

3 hydrogen bonds

Question 60

A:T and G:C had the same shape which meant

Answer 60

two pairs can fit in any order between backbones without distorting the structure

Question 61

Complementary base pairing (Chargaff ratios)

Answer 61

equals same amount

Question 62

Displacement of backbones generates

Answer 62

2 grooves 1 major (much wider) 1 minor groove

Question 63

B-form DNA

Answer 63

double helix spiral to the right

Question 64

most common form of DNA

Answer 64

B-form

Question 65

Z form

Answer 65

helix spirals to the left and the backbone takes on a zigzag shape

Question 66

Some viruses have

Answer 66

small, single-stranded DNA (omegaX174 and M13)

Question 67

Cicular and single stranded DNA is converted to

Answer 67

double helix during replication