Exam 3 Version 1

Question 1

What is a promoter?

Answer 1

A DNA sequence that is needed for the initiation of transcription

Question 2

Which type of RNA is NOT involved in the process of translation?

Answer 2

All of the above are involved in translation
(includes mRNA, rRNA, and tRNA)

Question 3

There are 61 ___ codons in the genetic code

Answer 3

Sense

Question 4

What complex is responsible for the formation of peptide bonds between amino acids?

Answer 4

C

Question 5

The role of tRNA is to deliver _______ during protein synthesis

Answer 5

A

Question 6

Choose the best answer

Answer 6

C

Question 7

Which of the following processes does NOT depend on complementary base pairing?

Answer 7

D

Question 8

A gene that is _______ is ‘on’ at all times

Answer 8

Constitutively expressed

Question 9

Which of the following statements about operons is INCORRECT?

Answer 9

Structural genes within an operon are transcribed independently of one another

Question 10

In an inducible operon, an inducer binds to the ________, pulling it off the operator and enabling transcription of the structural genes

Answer 10

Repressor

Question 11

If the lac operator was deleted from the lac operon

Answer 11

lacZYA would be expressed regardless of lactose concentration

Question 12

The structural genes in the lac operon are involved in the ____ of lactose. The structural genes in the trp operon are involved in the _____ of tryptophan

Answer 12

Breakdown, synthesis

Question 13

In a repressible operon, a(n) ________ binds to the repressor, which prevents transcription of the structural genes

Answer 13

Co-repressor

Question 14

Which of the following statements about mutations is FALSE

Answer 14

Mutations always have a negative effect on the fitness of an organism

Question 15

–

Answer 15

A

Question 16

Which of the following types of mutations is least likely to have an impact on the function of the encoded protein?

Answer 16

Synonymous

Question 17

A gene that moves to various different sites within a bacterial chromosome is likely positioned within a

Answer 17

Transposon

Question 18

Which of the following statements regarding plasmids is FALSE

Answer 18

Plasmids encode essential genes

Question 19

Horizontal gene transfer is a mechanism for bacterial populations to

Answer 19

Generate genetic diversity

Question 20

Horizontal gene transfer refers to DNA that is

Answer 20

Acquired from an external source

Question 21

If a bacterial cell is competent, it means that

Answer 21

The bacterium can import free DNA fragments and incorporate them into its genome

Question 22

Which of the following is encoded within a conjugative plasmid

Answer 22

Sex pilus

Question 23

Which of the following describes an F factor that has integrated into a bacterial chromosome?

Answer 23

Hfr

Question 24

Which of the following is necessary for the integration of foreign DNA into a host chromosome?

Answer 24

Recombination

Question 25

Which of the following is NOT an example of biotechnology?

Answer 25

Determining the ultrastructure of flagellar motors

Question 26

Methylation protects bacterial DNA from degradation due to _________

Answer 26

Restriction enzymes

Question 27

The enzyme BamHI recognizes the sequence 5’-GGATCC-3’ and cuts between the ‘GG’ within the sequence to produce a sticky end. What single-stranded overhang is produced as a result? (hint: DNA is double stranded)

Answer 27

5’-GATC-3’

Question 28

Which of the following steps is NOT a part of a PCR cycle?

Answer 28

Methylation

Question 29

How is progression through the steps and cycles of PCR controlled?

Answer 29

Change in temperature

Question 30

Several characteristics make E. coli and S.cerevisiae excellent model systems for recombinant DNA technology. Which of the following is NOT a reason?

Answer 30

Both are pathogenic

Question 31

What taxonomic ranks are included in binomial nomenclature?

Answer 31

Genus and species

Question 32

In biology, the current taxonomic system is based on _______

Answer 32

Evolutionary relatedness

Question 33

The species concept loses meaning when discussing bacteria because

Answer 33

Bacteria reproduce asexually rather than sexually

Question 34

Which of the following organelles is thought to have evolved from prokaryotic cells?

Answer 34

Mitochondrion

Answer 35

B

Question 36

All organisms require carbon but some organisms can only utilize carbon in certain chemical forms. The indicates the importance of

Answer 36

Biogeochemical cycling

Question 37

Algal blooms are caused by

Answer 37

Influx of nutrients

Question 38

Which food preservation method works by reducing the number of microbes present?

Answer 38

Pasteurization

Question 39

Why is boiling food contaminated by Clostridium botulinum ineffective for preventing botulism?

Answer 39

The botulism toxin is heat stable

Question 40

Which of the following is NOT a benefit of food fermentation?

Answer 40

Elimination of all microbes

Question 41

What primary reaction occurs during the fermentation of milk?

Answer 41

Carbohydrates –> lactic acid

Question 42

All of the following are essential components of chocolate production EXCEPT

Answer 42

Alkaline fermentation by mold (eg. Rhizopus)