Ch 8

Question 1

Describe how DNA serves as genetic information.

Answer 1

Flows from DNA to RNA to proteins.

replication-transcription-translation

Question 2

polymerase

Answer 2

copies DNA

Question 3

semiconservative

Answer 3

double helix of parent DNA splits to make daughter strand

*one old to make one new

Question 4

protein synthesis

Answer 4

translation from RNA

Question 5

transcription

Answer 5

DNA is transcribed to make RNA

*R in transcRibed for RNA

Question 6

What is the direction of DNA synthesis

Answer 6

5’ to 3’

Question 7

prokaryotes protein synthesis

Answer 7

simutaneous transcription and translation- single circular DNA

Question 8

eukaryotes protein synthesis

Answer 8

uses exons and introns- introns cut out and exons glued together w snRNPs

Question 9

operons

Answer 9

a set location of DNA that code for a gene

Question 10

operon examples

Answer 10

lac operon- induction

trp operon- repression

Question 11

3 parts of an operon

Answer 11

1. control region- where promoter located
2. operator- on/off switch
3. structural genes

Question 12

constitutive genes

Answer 12

expressed at a fixed rate

Question 13

repressible genes

Answer 13

on until off- blocks polymerase

Question 14

inducible genes

Answer 14

off until turned on- blocks polymerase

Question 15

catabolic genes

Answer 15

needs food source

Question 16

epigenetic control

Answer 16

methylating nucleotides- methylated (off) genes are passed to offspring

• not permanent
• biofilm behavior

Question 17

microRNA

Answer 17

RNA is degraded

Question 18

spontaneous mutations

Answer 18

occur in the absence of a mutagen

Question 19

base substitution mutation

Answer 19

point mutation w outcome of missense or nonsense mutation

Question 20

frameshift mutation

Answer 20

insertion or deletion of one or more nucleotide pairs

Question 21

chromosome

Answer 21

structure containing DNA that physically carries hereditary information; the chromosomes contain the genes

Question 22

gene

Answer 22

a segment of DNA that encodes a functional product, usually a protein

Question 23

DNA nucleotides

Answer 23

adenine, thymine, cytosine, and guanine

Question 24

DNA synthesis (6) 
Replication

Answer 24

1. DNA copied by DNA polymerase in the 5’-3’ direction
2. Initiated by an RNA primer
3. leading strand is synthesized continuously
4. lagging strand is synthesized discontinuously
5. Okazaki fragments
6. RNA primers are removed and Okazaki fragments joined by a DNA polymerase and DNA ligase

Question 25

replication fork

Answer 25

point where strands of DNA split

Question 26

outcome from base mutation

Answer 26

missense (change in amino acid) or nonsenses mutation (results in a stop codon)

Question 27

how are mutations repaired?

Answer 27

photolyase- seperates thymine dimers | excision repair

Question 28

horizontal gene transfer

Answer 28

transfer of genes between cells of the same generation

Question 29

4 methods of horizontal gene transfer

Answer 29

1. genetic transformation 2. genetic recombination 3. conjugation 4. transduction by bacteriophage

Question 30

vertical gene transfer

Answer 30

occurs during reproduction between generation of cells- parent to daughter cell

Question 31

plasmids

Answer 31

contain genes for resistance (antibiotic), conjugation (sex pili), and production of toxins

Question 32

transposons

Answer 32

segments of DNA that can move from one region to another

Question 33

promoter

Answer 33

starts transcription process- where RNA polymerase binds to the DNA strand

Question 34

terminator

Answer 34

stop codon that ends transcription

Question 35

codon

Answer 35

3 nucleotide sequence where mRNA is translated | AUG- start codon

Question 36

anticodon

Answer 36

codons found on the tRNA

Question 37

mRNA

Answer 37

created at the end of transcription- what codes the DNA

Question 38

ribosome

Answer 38

where protein synthesis occurs

Question 39

rRNA

Answer 39

makes up a ribosome

Question 40

tRNA

Answer 40

transfer RNA that bring the amino acid that combines with the mRNA to make proteins