BIOD 210 Exam 4 | Questions and Answers Latest
Updated (Graded A+)- Portage Learning
1. Explain how have multidrug-resistant pathogens in agriculture been
propagated.
Livestock and animals are provided food treated with continuous low-
dose antibiotics, which are used to enhance the growth of the animals.
Over time, bacteria accrue mutations that lead to resistance to these
antibiotics and eventually pathogenic bacteria are borne with the
same resistance, and standard antibiotic treatment no longer works.
2. Explain how have multidrug resistant pathogens in health clinics been
propagated
For many years, the first course of treatment for illness was
antibiotics. Health providers would use these drugs regardless of
being able to diagnose illnesses as bacterial, viral, or something
altogether different. Over time, the overuse of antibiotics led to
bacteria that accrued mutations leading to resistance. Eventually
more pathogenic bacteria arose with the same resistance, and
standard antibiotic treatment no longer worked
3. When the bacteria are cultured but separated by a filter so that they
cannot directly touch, one of the bacterial strains can grow well on
minimal medium. What type of genetic transmission occurred in this
experiment? Explain how you know.
Transduction occurred in this experiment because the bacteria did not
require direct contact to transmit the genetic material, like it
would’ve happened with conjugation.
4. Two auxotrophic bacterial strains are propagated in the laboratory,
one deficient for leucine and the other deficient for biotin. When
cultured alone, they cannot grow on minimal medium, and when
combined in the same culture media, they still cannot grow in the
minimal media. Can you tell if genetic transmission occurred in this
experiment in the case of genes that control synthesis of biotin or
leucine?
It does not appear that genetic transmission has occurred in this
experiment involving these genes because even with direct contact,
there is no growth rescue for either of these auxotrophs.
5. Does spontaneous mutation positively or negatively affect evolution?
Briefly explain your answer.
Spontaneous mutations positively affect evolution because the
, mutations that make the organism better able to function or tolerate
its environment help it to survive longer than its wild-type
counterparts. The longer-lived organisms are likely to produce more
offspring than those with short survival times. Thus, an advantageous
mutation will be passed on to future generations, and if it truly
enhances survival, it will eventually become the normal (wild-type)
gene.
6. True or False: A bacterium that can grow well on a minimal medium is
an example of an auxotroph.
False
7. True or False: A bacterium that can grow well on a minimal medium is
an example of an prototroph.
True
8. Fill in the blank: A bacterium that can grow well on minimal medium
is an example of a .
Prototroph
9. Match the following terms with the correct description: Enzyme,
Prophage, Gratuitous Inducer, Structural Gene, Operon.
a) Acts as a catalyst for a biochemical reaction - enzyme
b) Clusters of genes and the region that activates them - operon
c) Activates genes but are substrates for enzymes – gratuitous
inducer
c) Gene not involved in the biochemical reaction – structural
gene
d) Virus DNA integrated into a bacterial chromosome - prophage
10. The activity of a gene that happens most of the time and results
in only a few copies of the gene being constantly produced before it is
called upon for activity is called the .
Basal level
11. IPTG is a inducer of the lac operon
Gratuitous
12. A gene that is expressed all of the time regardless of conditions
is called:
a) Permanent
b) Constitutive
Updated (Graded A+)- Portage Learning
1. Explain how have multidrug-resistant pathogens in agriculture been
propagated.
Livestock and animals are provided food treated with continuous low-
dose antibiotics, which are used to enhance the growth of the animals.
Over time, bacteria accrue mutations that lead to resistance to these
antibiotics and eventually pathogenic bacteria are borne with the
same resistance, and standard antibiotic treatment no longer works.
2. Explain how have multidrug resistant pathogens in health clinics been
propagated
For many years, the first course of treatment for illness was
antibiotics. Health providers would use these drugs regardless of
being able to diagnose illnesses as bacterial, viral, or something
altogether different. Over time, the overuse of antibiotics led to
bacteria that accrued mutations leading to resistance. Eventually
more pathogenic bacteria arose with the same resistance, and
standard antibiotic treatment no longer worked
3. When the bacteria are cultured but separated by a filter so that they
cannot directly touch, one of the bacterial strains can grow well on
minimal medium. What type of genetic transmission occurred in this
experiment? Explain how you know.
Transduction occurred in this experiment because the bacteria did not
require direct contact to transmit the genetic material, like it
would’ve happened with conjugation.
4. Two auxotrophic bacterial strains are propagated in the laboratory,
one deficient for leucine and the other deficient for biotin. When
cultured alone, they cannot grow on minimal medium, and when
combined in the same culture media, they still cannot grow in the
minimal media. Can you tell if genetic transmission occurred in this
experiment in the case of genes that control synthesis of biotin or
leucine?
It does not appear that genetic transmission has occurred in this
experiment involving these genes because even with direct contact,
there is no growth rescue for either of these auxotrophs.
5. Does spontaneous mutation positively or negatively affect evolution?
Briefly explain your answer.
Spontaneous mutations positively affect evolution because the
, mutations that make the organism better able to function or tolerate
its environment help it to survive longer than its wild-type
counterparts. The longer-lived organisms are likely to produce more
offspring than those with short survival times. Thus, an advantageous
mutation will be passed on to future generations, and if it truly
enhances survival, it will eventually become the normal (wild-type)
gene.
6. True or False: A bacterium that can grow well on a minimal medium is
an example of an auxotroph.
False
7. True or False: A bacterium that can grow well on a minimal medium is
an example of an prototroph.
True
8. Fill in the blank: A bacterium that can grow well on minimal medium
is an example of a .
Prototroph
9. Match the following terms with the correct description: Enzyme,
Prophage, Gratuitous Inducer, Structural Gene, Operon.
a) Acts as a catalyst for a biochemical reaction - enzyme
b) Clusters of genes and the region that activates them - operon
c) Activates genes but are substrates for enzymes – gratuitous
inducer
c) Gene not involved in the biochemical reaction – structural
gene
d) Virus DNA integrated into a bacterial chromosome - prophage
10. The activity of a gene that happens most of the time and results
in only a few copies of the gene being constantly produced before it is
called upon for activity is called the .
Basal level
11. IPTG is a inducer of the lac operon
Gratuitous
12. A gene that is expressed all of the time regardless of conditions
is called:
a) Permanent
b) Constitutive
