exam 3

Question 1

In multi-cell organisms, mutations can be ________ or ________

Answer 1

somatic or germ-line

Question 2

True or False: In single cell organisms, all daughter cells have the mutation

Answer 2

True

Question 3

Somatic mutations are passed to

Answer 3

Daughter cells in the area

Question 4

Germ-line mutations are passed to

Answer 4

Offspring

Question 5

Why are mistakes in transcription or translation not as critical?

Answer 5

1. Many copies of RNA are produced
2. RNAs are not heritable over multiple generations

Question 6

lacl+ is

Answer 6

wild type

Question 7

lacl- is

Answer 7

mutated

Question 8

3 factors that can change DNA sequences

Answer 8

1. uncorrected replication mistakes
2. chemical mutagens
3. high-intensity radiation

Question 9

Base substitution

Answer 9

replace one base pair with another

Question 10

Same sense mutation

Answer 10

nucleotide changed to different codon that specifies the same amino acid

Question 11

Nonsense mutation

Answer 11

codon specifying amino acid is changed to a stop codon

Question 12

Missense mutation

Answer 12

codon specifying amino acid is changed to a codon for a different amino acid

Question 13

Sickle cell anemia is caused by

Answer 13

defective beta-globin subunit in hemoglobin protein

Question 14

phenylketonuria is caused by

Answer 14

a single amino acid change in a 451 amino acid enzyme

Question 15

frameshift mutation

Answer 15

addition or removal of a small number of bases not divisible by three which disrupts the normal reading frame in the mRNA

Question 16

Cystic fibrosis is characterized by the faulty protein

Answer 16

CTFR

Question 17

some lymphomas and leukemias are caused by

Answer 17

translocations

Question 18

many oncogenes are activated and become cancers through

Answer 18

duplications

Question 19

fragile x syndrome and huntingtin’s disease are also caused by duplications of

Answer 19

short, repeated sequences

Question 20

If _______ don’t involve the loss of DNA, they are often silent, but have been kown to cause infertility

Answer 20

inversions

Question 21

Haemophilia A is caused by

Answer 21

insertions

Question 22

Duchenne’s Muscular Dystrophy is caused by a

Answer 22

deletion

Question 23

actin monomers are

Answer 23

highly folded globular proteins

Question 24

Polymerization begins with

Answer 24

nucleation

Question 25

polymerization is favored at the

Answer 25

plus (barbed) end

Question 26

depolymerization is favored at the

Answer 26

minus (pointed) end

Question 27

6 types of binding proteins

Answer 27

1. monomer binding 2. filament severing 3. filament bundling 4. filament crosslinking 5. filament capping 6. filament anchoring

Question 28

Actin networks provide

Answer 28

structural stability, but are more flexible than bundles

Question 29

Myosin

Answer 29

a motor protein that converts chemical energy (ATP) into mechanical energy, generating force and movement

Question 30

Actin and myosin are responsible for

Answer 30

cell division, cell crawling, some vesicle movement, and muscle contraction

Question 31

Microtubules can be used for

Answer 31

1. intracellular transport 2. segregating chromosomes during mitosis 3. propulsion/sweeping of fluids over membranes

Question 32

Microtubules are

Answer 32

rigid, hollow, tubes made of tubulin

Question 33

Tubulin

Answer 33

a dimer of alpha-tubulin and beta-tubulin

Question 34

Marfan Syndrome

Answer 34

FBN1, frameshift, nonsense, deletions

Question 35

Progeria

Answer 35

LMNA, missense

Question 36

Tay-Sachs disease

Answer 36

HexA, frameshift, nonsense, deletions

Question 37

Promoter mutation

Answer 37

may increase or decrease the rate of transcription

Question 38

Transcriptional regulatory element/operator site mutation

Answer 38

may alter the regulation of transcription

Question 39

Splice sites mutation

Answer 39

may alter ability of pre-mRNA to be properly spliced

Question 40

Translational regulatory element mutation

Answer 40

may alter the ability of mRNA to be translationally regulated

Question 41

Intergenic region mutation

Answer 41

not as likely to have an effect on gene expression

Question 42

Direct Repair

Answer 42

repair enzyme recognizes an incorrect structure in the DNA and directly restores the correct structure

Question 43

Base excision and Nucleotide excision repair

Answer 43

abnormal base/nucleotide is recognized, and a portion of the strand containing the abnormality is removed. complementary strand is then used to synthesize normal strand

Question 44

Methyl-directed mismatch repair

Answer 44

like excision repair but the defect is a base pair mismatch. The region with the error is removed and the complementary strand synthesizes a normal strand

Question 45

Oncogene

Answer 45

mutant gene that promotes uncontrolled cell growth

Question 46

tumor-suppressor gene

Answer 46

normal gene that encodes proteins to help prevent cancer