Ch. 15

Question 1

set of 3 nucleotides that specifies a particular amino acid

Answer 1

codon

Question 2

information flows in one direction: DNA to RNA to protein

Answer 2

central dogma

Question 3

flow of info from DNA to RNA

Answer 3

transcription

Question 4

flow of info from RNA to protein

Answer 4

translation

Question 5

each enzyme of the arginine pathway was encoded by a separate gene

Answer 5

one gene - one polypeptide hypothesis

Question 6

how many possible codons?

Answer 6

64

Question 7

stop codons

Answer 7

UAA, UGA, UAG

Question 8

start codon

Answer 8

AUG

Question 9

Template strand

Answer 9

strand of DNA
antisense strand
3’ to 5’

Question 10

coding strand

Answer 10

complementary to template strand
sense strand
5’ to 3’

Question 11

transcription initiation

Answer 11

rna ploymerase idetneifies where to begin transcription - at the promoter region

Question 12

transcription elongation

Answer 12

rna nucleotides are added to the 3’ end of RNA strand

Question 13

Transcription termination

Answer 13

RNA polymerase stops translation when it encounters stop codon

Question 14

mRNA

Answer 14

messenger
carries info from RNA that encodes protein

Question 15

rRNA

Answer 15

ribosomal
structural component of ribosome

Question 16

tRNA

Answer 16

transfer
carrier amino acids to the ribosome for translation

Question 17

snRNA

Answer 17

small nuclear
involved in pre-RNA splicing

Question 18

transcription buble

Answer 18

moves at rate of 50 nucleotides/sec
consists of:
RNA poly
DNA template
growing RNA transcript

Question 19

RNA pol I

Answer 19

transcribes tRNA

Question 20

RNA pol II

Answer 20

transcribes mRNA and some snRNA

Question 21

RNA pol III

Answer 21

transcribes tRNA and some other small RNA

Question 22

common promoter region

Answer 22

TATA box

Question 23

for transcript to leave the nucleus into cytoplasm it needs

Answer 23

5’ cap
3’ poly-A tail
removal of non-coding sequences (introns)

Question 24

organelle responsible for removing introns and splicing exons together

Answer 24

splicesome

Question 25

non-coding sequences

Answer 25

introns

Question 26

sequences that will be translated

Answer 26

exons

Question 27

what is alternative splicing?

Answer 27

recombination of different exons

Question 28

importance of alternative splicing

Answer 28

major source of genetic diversity in eukaryotes

Question 29

final 3-D structure of tRNA

Answer 29

L-Shaped structure

Question 30

tRNA carry

Answer 30

amino acids to ribosome to make polypeptide

Question 31

P Site

Answer 31

binds the tRNA attached to growing peptide chain

Question 32

A site

Answer 32

binds the tRNA carrying next amino acid

Question 33

E site

Answer 33

binds the tRNA that carried the last amino acid

Question 34

2 primary functions of the ribosome

Answer 34

decode mRNA form peptide bonds

Question 35

enzyme component of the ribosome that forms peptide bonds between amino acids

Answer 35

peptidyl transferase

Question 36

translation initiation

Answer 36

joining of 5' end of mRNA with large and small ribosomal subunit

Question 37

first tRNA molecule in translation is at

Answer 37

P Site

Question 38

translation elongation

Answer 38

requires elongation factors addition of amino acids charged tRNA binds to A site peptidyl transferase forms peptide bond ribosome moves down the mRNA in 5' to 3' direction

Question 39

wobble phenomenon

Answer 39

allows less stringent pairing between 3' base of the codon and the 5' base of anticodon

Question 40

translation termination

Answer 40

elongation continues until stop codon stop codons recognized by release factors

Question 41

point mutation

Answer 41

alter single base classification of mutation

Question 42

silent mutation

Answer 42

substitute one base for another doesn't change amino acid

Question 43

missense mutation

Answer 43

substitutes one base for another cause coding for another amino acid

Question 44

nonsense mutation

Answer 44

subsites one base for another, coded for stop codon

Question 45

frameshift mutation

Answer 45

caused by insertion or deletion of a single base

Question 46

triple repeat expansion mutation

Answer 46

sequence of 3 DNA nucleotides are repeated many times

Question 47

chromosomal mutation

Answer 47

change structure of chromosome

Question 48

deletion

Answer 48

part of chromosome is lost

Question 49

duplication

Answer 49

part of chromosome is copied

Question 50

inversion

Answer 50

part of the chromosome in reverse order