Biol 251 Exam 2 Unr (HW +
LC Questions) With Correct
Solutions
Which mutation results in an error in the mRNA just after the start codon,
is likely to have the most serious effect on the resulting protein? -
CORRECT ANSWER- deletion of two nucleotides
In the lac operon, what role does allolactose play? - CORRECT
ANSWER- inducer
Which are true when high levels of glucose and lactose are available to
a cell? - CORRECT ANSWER- cAMP levels are low, allolactose
binds to the repressor, the cell utilizes glucose
In the trp operon, what role does tryptophan play? - CORRECT
ANSWER- corepressor
What would happen if the trp repressor protein were mutated and could
no longer bind to tryptophan? - CORRECT ANSWER- the cell would
always produce tryptophan
Types of organisms able to grow at refrigeration temperatures? -
CORRECT ANSWER- psychrotrophs and psychrophiles
Specialized transduction differs from generalized transduction in that
specialized transudction - CORRECT ANSWER- may only transfer
particular segments of bacterial DNA to the recipient
Bacterial growth refers to an increase in the numbers of cells in a
bacterial culture - CORRECT ANSWER- True
, Most bacteria reproduce by - CORRECT ANSWER- binary fission
What results when a single bacterium reproduces? - CORRECT
ANSWER- Two genetically identical daughter cells
You begin with 6 cells. How many are there after 3 rounds of division?
- CORRECT ANSWER- 48 cells
Which is NOT a step in bacterial cell division? - CORRECT ANSWER-
Disappearance of a nuclear envelope
Which step of binary fission is the reason for genetically identical
daughter cells? - CORRECT ANSWER- replication of bacterial
chromosome
Chemical requirements for microbial growth include Carbon, Nitrogen,
Phosphorus, and Sulfur. Why do all cells need Nitrogen? - CORRECT
ANSWER- for building amino acids, proteins, and nucleic acids
Salts and sugars work to preserve foods by creating a - CORRECT
ANSWER- hypertonic environment
Bacteria that can grow in the presence or absence of Oxygen are called
- CORRECT ANSWER- facultative anaerobes
Which microbe classification is mismatched with optimal growth
temperatures? - CORRECT ANSWER- thermophile --- grow at 37
degrees C
wrong bc thermo = heat loving (41-122 C)
Microbes have very narrow optimum temperature ranges. Which of the
following classifications of microbes are most likely to cause human
disease, based on their temperature requirements? - CORRECT
ANSWER- mesophiles
Patients with indwelling catheters are susceptible to infections because
- CORRECT ANSWER- biofilms develop on catheters
LC Questions) With Correct
Solutions
Which mutation results in an error in the mRNA just after the start codon,
is likely to have the most serious effect on the resulting protein? -
CORRECT ANSWER- deletion of two nucleotides
In the lac operon, what role does allolactose play? - CORRECT
ANSWER- inducer
Which are true when high levels of glucose and lactose are available to
a cell? - CORRECT ANSWER- cAMP levels are low, allolactose
binds to the repressor, the cell utilizes glucose
In the trp operon, what role does tryptophan play? - CORRECT
ANSWER- corepressor
What would happen if the trp repressor protein were mutated and could
no longer bind to tryptophan? - CORRECT ANSWER- the cell would
always produce tryptophan
Types of organisms able to grow at refrigeration temperatures? -
CORRECT ANSWER- psychrotrophs and psychrophiles
Specialized transduction differs from generalized transduction in that
specialized transudction - CORRECT ANSWER- may only transfer
particular segments of bacterial DNA to the recipient
Bacterial growth refers to an increase in the numbers of cells in a
bacterial culture - CORRECT ANSWER- True
, Most bacteria reproduce by - CORRECT ANSWER- binary fission
What results when a single bacterium reproduces? - CORRECT
ANSWER- Two genetically identical daughter cells
You begin with 6 cells. How many are there after 3 rounds of division?
- CORRECT ANSWER- 48 cells
Which is NOT a step in bacterial cell division? - CORRECT ANSWER-
Disappearance of a nuclear envelope
Which step of binary fission is the reason for genetically identical
daughter cells? - CORRECT ANSWER- replication of bacterial
chromosome
Chemical requirements for microbial growth include Carbon, Nitrogen,
Phosphorus, and Sulfur. Why do all cells need Nitrogen? - CORRECT
ANSWER- for building amino acids, proteins, and nucleic acids
Salts and sugars work to preserve foods by creating a - CORRECT
ANSWER- hypertonic environment
Bacteria that can grow in the presence or absence of Oxygen are called
- CORRECT ANSWER- facultative anaerobes
Which microbe classification is mismatched with optimal growth
temperatures? - CORRECT ANSWER- thermophile --- grow at 37
degrees C
wrong bc thermo = heat loving (41-122 C)
Microbes have very narrow optimum temperature ranges. Which of the
following classifications of microbes are most likely to cause human
disease, based on their temperature requirements? - CORRECT
ANSWER- mesophiles
Patients with indwelling catheters are susceptible to infections because
- CORRECT ANSWER- biofilms develop on catheters
