Ap Biology Exam: Molecular Genetics

Front 1

what are the four nitrogen bases

Back 1

1. cytosine

2. guanine

3. adenine

4. thymine

Front 2

what nitrogen bases are purines

Back 2

adenine and guanine

Front 3

what is a purine

Back 3

double ringed

Front 4

what bases are pyrimidines

Back 4

thymine and cytosine

Front 5

what is a pyrimidine

Back 5

single ringed

Front 6

what makes up DNA

Back 6

nucleotides

Front 7

what makes up a nucleotide

Back 7

1. five carbon sugar

2. phosphate group

3. nitrogenous base

Front 8

what are the two base pairs

Back 8

1. adenine and thymine (by two hydrogen bonds)

2. cytosine and guanine (by three hydrogen bonds)

Front 9

what is the difference between the 5' end and the 3' end

Back 9

5' end: phosphate group

3' end: hydroxyl group (OH)

Front 10

helicase

Back 10

unwinds double helix in to 2 separate stands of DNA

Front 11

polymerase

Back 11

adds nucleotides to existing single strand

Front 12

ligase

Back 12

brings together Okazaki fragments

Front 13

topoisomerase

Back 13

cuts and rejoins the helix

Front 14

RNA primase

Back 14

catalyzes the synthesis of RNA primers

Front 15

what are the differences between DNA and RNA

Back 15

1. RNA is single stranded and DNA is double stranded

2. RNA has ribose sugar and DNA has deoxyribose sugar

3. RNA has the base uracil instead of thymine in DNA

Front 16

what are the three types of RNA

Back 16

1. mRNA

2. rRNA

3. tRNA

Front 17

what is mRNA

Back 17

copies and carries stored DNA info to ribosome

Front 18

what is rRNA

Back 18

synthesizes protein

Front 19

what is tRNA

Back 19

reads mRNA message, shuttles amino acids to ribosome

Front 20

what are the three stages in transcription

Back 20

1. initiation

2. elongation

3. termination

Front 21

at what site does transcription begin

Back 21

promoter

Front 22

only one DNA strand is copied, and this is called the

Back 22

sense strand or the template strand

Front 23

the other uncopied strand is known as the

Back 23

nonsense strand

Front 24

RNA molecules replace DNA thymine with what

Back 24

uracil

Front 25

exons

Back 25

coding regions of mRNA that expresses the code for the polypeptide

Front 26

introns

Back 26

noncoding regions of mRNA

Front 27

codon

Back 27

a group of three bases (letters) that code for one (of 20) amino acids

Front 28

RNA processing includes 3 ideas

Back 28

1. poly A tail on the 3' end

2. 5' end GTP cap

3. spliceosomes to rid the mRNA of introns

Front 29

point mutation

Back 29

one base is substituted for another

Front 30

nonsnese mutation (point mutation)

Back 30

early termination of protein synthesis

Front 31

missense mutation (point)

Back 31

codon altered producing a different amino acid

Front 32

silent mutation (point)

Back 32

creates a new codon that results in the same amino acid

Front 33

insertion (frameshift)

Back 33

gain of gene

Front 34

deletion (frameshift)

Back 34

loss of a gene

Front 35

duplication

Back 35

extra copy of genes caused by unequal crossing over

Front 36

inversion

Back 36

when letters are reversed

Front 37

translocation

Back 37

when a portion of two different chromosomes breaks and rejoins in a way that the DNA sequence is lost, repeated, or interrupted

Front 38

recombinant DNA

Back 38

generated by combining DNA from multiple sources to create a unique DNA that is not found in nature