Unit 3

Question 1

first discovered dna

Answer 1

frederick miescher

Question 2

discovered that dna contained phospates

Answer 2

phoebus a. t. levine

Question 3

discovered the helical structure by xray crystallography

Answer 3

rosalind franklin

Question 4

described the 3-dimensional structure of the DNA molecule

Answer 4

james watson and francis crick

Question 5

carries genetic information for the development and functioning of an organism

Answer 5

dna (deoxyribonucleic acid)

Question 6

two types of dna that contain their genes

Answer 6

chromosomes and extra chromosomes

Question 7

chromosomes and extra chromosomes example

Answer 7

plasmid

Question 8

circular, double stranded dna attached to bacterial cell membrane

Answer 8

bacterial chromosomes

Question 9

self-replicating extra chromosomal dna molecules

Answer 9

plasmids

Question 10

types of plasmids

Answer 10

r factors, col factors, f (fertility) factors

Question 11

code for antibiotic resistance

Answer 11

r factor

Question 12

code for extracellular toxin production

Answer 12

col factors

Question 13

plasmid that recombine itself with the bacterial chromosome

Answer 13

fertility factor

Question 14

it is due to chemical alteration in dna

Answer 14

mutation

Question 15

it could be spontaneous by chemical or physical means

Answer 15

mutation

Question 16

one or more bases in there dna are altered

Answer 16

mutation

Question 17

types of mutation

Answer 17

substitution, deletion, insertion

Question 18

change of a single base

Answer 18

substitution

Question 19

loss of a base

Answer 19

deletion

Question 20

addition of a base

Answer 20

insertion

Question 21

alter the dna gene content of bacteria

Answer 21

gene transfer

Question 22

types of gene transfer

Answer 22

transformation, transduction, conjugation, transposition

Question 23

occurs when plasmid dna is transferred from donor to recipient

Answer 23

conjugation

Question 24

mechanism which enhances genetic flexibility among plasmids and bacterial chromosomes

Answer 24

transposition

Question 25

segments of dna that can transpose or move extremely readily

Answer 25

transposons

Question 26

other name for transposons

Answer 26

jumping genes

Question 27

occurs when fragments of exogenous bacterial dna are taken up and absorbed

Answer 27

transformation

Question 28

the recipient bacterium must be competent to absorb the exogenous fragments of bacterial dna

Answer 28

competence

Question 29

transformation of genes from one bacterium to another results in:

Answer 29

a) change in pathogenicity of the bacterium b) change in the antibiotic sensitivity pattern of bacterium

Question 30

occurs when fragments of chromosomal dna is transferred or transduced into a second bacterium by phage

Answer 30

transduction