Page 1 of 122
LAB PRACTICUM & EXAM 3: BIOS252 / BIOS 252
ANATOMY & PHYSIOLOGY II WITH LAB (LATEST 2025
UPDATES STUDY BUNDLE WITH COMPLETE SOLUTIONS)
| 100% CORRECT | GRADE A - CHAMBERLAIN
Which term would be applied to a regulatory condition that
occurs when protein is associated with a particular section of
DNA and greatly reduces transcription? .....ANSWER.....negative
control
In the diagram below, what type of control, positive or negative,
is operating?
-{ }( )-|-structrual gene-
^
{regulatory protien}
makes a transcription. .....ANSWER.....positive control
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T/F Under a system of positive control, transcription does not
occur unless a regulator molecule directly stimulates RNA
production. .....ANSWER.....True
T/F Under a system of negative control, genetic expression
occurs unless some form of regulator shuts off such expression.
.....ANSWER.....True
Which term is used to describe enzymes that are produced only
when specific substrates are present in the environment?
.....ANSWER.....inducible: This term best describes enzymes that
are produced only when specific substrates are present in the
environment to induce their production.
Which term refers to a contiguous genetic complex that is under
coordinated control? .....ANSWER.....operon
Things to define .....ANSWER.....allosteric
lysogen
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attenuation
prototroph
operon
Cryan experiments with gut microbes
16 interaction
17 interaction
Which of the following mutations could lead to constitutive
expression of the genes of the lac operon? .....ANSWER.....A
mutation in the operator sequence. Such a mutation could prevent
binding of the repressor, allowing expression under all
conditions.
Which of the following best describes the biological role of the
lac operon? .....ANSWER.....It ensures that a cell dedicates
resources to the production of enzymes involved in lactose
metabolism only when lactose is available in the environment. The
, Page 4 of 122
cell expends energy to produce the proteins necessary for
lactose metabolism only when lactose is present.
T/F The placement of the operator sequence between the
promotor and the structural genes is critical to the proper function
of the lac operon. .....ANSWER.....True. When the repressor binds
to the operator, RNA polymerase cannot transcribe the structural
genes.
In the lac operon, the product of structural gene lacZ is capable
of ________. .....ANSWER.....splitting the β-linkage of lactose
Which term most appropriately refers to a regulatory protein in
prokaryotes? .....ANSWER.....DNA binding protein
A constitutive mutation in the lac operon may be of several types.
Name two types of constitutive mutations. .....ANSWER.....lacOc,
lacI-
LAB PRACTICUM & EXAM 3: BIOS252 / BIOS 252
ANATOMY & PHYSIOLOGY II WITH LAB (LATEST 2025
UPDATES STUDY BUNDLE WITH COMPLETE SOLUTIONS)
| 100% CORRECT | GRADE A - CHAMBERLAIN
Which term would be applied to a regulatory condition that
occurs when protein is associated with a particular section of
DNA and greatly reduces transcription? .....ANSWER.....negative
control
In the diagram below, what type of control, positive or negative,
is operating?
-{ }( )-|-structrual gene-
^
{regulatory protien}
makes a transcription. .....ANSWER.....positive control
,Page 2 of 122
T/F Under a system of positive control, transcription does not
occur unless a regulator molecule directly stimulates RNA
production. .....ANSWER.....True
T/F Under a system of negative control, genetic expression
occurs unless some form of regulator shuts off such expression.
.....ANSWER.....True
Which term is used to describe enzymes that are produced only
when specific substrates are present in the environment?
.....ANSWER.....inducible: This term best describes enzymes that
are produced only when specific substrates are present in the
environment to induce their production.
Which term refers to a contiguous genetic complex that is under
coordinated control? .....ANSWER.....operon
Things to define .....ANSWER.....allosteric
lysogen
,Page 3 of 122
attenuation
prototroph
operon
Cryan experiments with gut microbes
16 interaction
17 interaction
Which of the following mutations could lead to constitutive
expression of the genes of the lac operon? .....ANSWER.....A
mutation in the operator sequence. Such a mutation could prevent
binding of the repressor, allowing expression under all
conditions.
Which of the following best describes the biological role of the
lac operon? .....ANSWER.....It ensures that a cell dedicates
resources to the production of enzymes involved in lactose
metabolism only when lactose is available in the environment. The
, Page 4 of 122
cell expends energy to produce the proteins necessary for
lactose metabolism only when lactose is present.
T/F The placement of the operator sequence between the
promotor and the structural genes is critical to the proper function
of the lac operon. .....ANSWER.....True. When the repressor binds
to the operator, RNA polymerase cannot transcribe the structural
genes.
In the lac operon, the product of structural gene lacZ is capable
of ________. .....ANSWER.....splitting the β-linkage of lactose
Which term most appropriately refers to a regulatory protein in
prokaryotes? .....ANSWER.....DNA binding protein
A constitutive mutation in the lac operon may be of several types.
Name two types of constitutive mutations. .....ANSWER.....lacOc,
lacI-
