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

Ribosome

Question 5

The role of tRNA is to deliver _______ during protein synthesis

Answer 5

An amino acid

Question 6

Choose the best answer

Answer 6

Both A + B:
A: Multiple copies of an mRNA can be produced from the same gene
B: Multiple copies of a protein can be produced from the same mRNA

Question 7

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

Answer 7

Protein folding

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

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

Answer 15

Synonymous

Question 16

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

Answer 16

Transposon

Question 17

Which of the following statements regarding plasmids is FALSE

Answer 17

Plasmids encode essential genes

Question 18

Horizontal gene transfer is a mechanism for bacterial populations to

Answer 18

Generate genetic diversity

Question 19

Horizontal gene transfer refers to DNA that is

Answer 19

Acquired from an external source

Question 20

If a bacterial cell is competent, it means that

Answer 20

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

Question 21

Which of the following is encoded within a conjugative plasmid

Answer 21

Sex pilus

Question 22

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

Answer 22

Hfr

Question 23

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

Answer 23

Recombination

Question 24

Which of the following is NOT an example of biotechnology?

Answer 24

Determining the ultrastructure of flagellar motors

Question 25

Methylation protects bacterial DNA from degradation due to _________

Answer 25

Restriction enzymes

Question 26

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 26

5'-GATC-3'

Question 27

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

Answer 27

Methylation

Question 28

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

Answer 28

Change in temperature

Question 29

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

Answer 29

Both are pathogenic

Question 30

What taxonomic ranks are included in binomial nomenclature?

Answer 30

Genus and species

Question 31

In biology, the current taxonomic system is based on _______

Answer 31

Evolutionary relatedness

Question 32

The species concept loses meaning when discussing bacteria because

Answer 32

Bacteria reproduce asexually rather than sexually

Question 33

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

Answer 33

Mitochondrion

Question 34

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

Answer 34

Biogeochemical cycling

Question 35

Algal blooms are caused by

Answer 35

Influx of nutrients

Question 36

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

Answer 36

Pasteurization

Question 37

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

Answer 37

The botulism toxin is heat stable

Question 38

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

Answer 38

Elimination of all microbes

Question 39

What primary reaction occurs during the fermentation of milk?

Answer 39

Carbohydrates --> lactic acid

Question 40

All of the following are essential components of chocolate production EXCEPT

Answer 40

Alkaline fermentation by mold (eg. Rhizopus)

Question 41

[review 3 mechanisms of HGT: transformation ,conjugation, transduction]