MICR 4423 (ACTUAL 2025/2026) EXAM 5 QUESTIONS WITH
100% VERIFIED CORRECT ANSWERS
Name 5 factors that interact with the human gut microbiota
either unidirectionally or bidirectionally. - ---Ans----1. Diet
2. Exercise
3. Age
4. Stress
5. Hormones
Is the gut microbiota relatively insensitive to conditions, or
does it respond quickly to changing conditions? - ---Ans----It
is highly responsive. It changes very quickly to all sorts of
different conditions.
How could you test the effect of a particular host gene on the
gut microbiota? - ---Ans----Use a mouse model where you
could make a knockout of that gene and then see if the
microbiota changed.
How could you test whether a particular microbiotal
composition can affect a host phenotype? - ---Ans----
Transplant the microbiota, isolated from feces, in a germ free
mouse, and assess the phenotype after that microbiota takes
residence in the mouse.
,How is a fecal microbiotal transplant (FMT) achieved? - ---
Ans----Homogenize feces in a sterile buffer, filter it to remove
undigested food structures and solid matter, administer just
the purified bacteria to the recipient.
Name two changes in host factors/behavior that impact that
microbiota such that it can change a host phenotype when
transplanted. - ---Ans----1. Changes in diet (moving from a
high fat, low fiber diet to a low fat, high fiber diet)
2. Changes in circadian rhythm.
How do we initially get our gut microbiome? - ---Ans----We
are inoculated in very early life, especially from our mothers
and from the early foods that we eat.
When does our microbiome transition from the infant-type
microbiome to the adult-type microbiome? - ---Ans----From
ages one to two, as we are weaned.
What is the "bacterial baptism" hypothesis, what practice has it
led to, and why is it contested? - ---Ans----The idea that we
obtain an initially healthy microbiome from our mothers during
the process of vaginal birth. It has led to the idea of vaginal
seeding, where vaginal fluids are wiped onto a baby's face or
body using sterile gauze after the baby is born.
The evidence that bacterial baptism is important has many
confounding factors, so some scientists have urged caution
, around vaginal seeding because it is not fully understood
whether those bacteria are really important.
When is our gut microbiome most important for future health?
- ---Ans----During the first two years of life.
Given the importance of the early microbiome, what is one
practical way that parents can try to guard against harmful
alterations to their child's microbiome? - ---Ans----Parents
can be conservative when using antibiotics. We can also be on
the lookout for ways to restore the microbiome ilike using
probiotics or making diet changes n cases where antibiotics
must be used.
What strategies might future interventions employ to stabilize
and restore the human gut microbiome in a person? - ---Ans-
---Specific diets, probiotic use, or in some cases fecal
microbiotal transfer.
What are three benefits that the gut microbiota provides for a
human host? - ---Ans----1. It helps break down otherwise
indigestible food structures such as cellulose.
2. Production of compounds that promote immune system
development and health.
3. Contributes to glucose homeostasis in our blood.
About how many antibiotic-resistant bacterial infections occur
in the United States each year? How many deaths from such
100% VERIFIED CORRECT ANSWERS
Name 5 factors that interact with the human gut microbiota
either unidirectionally or bidirectionally. - ---Ans----1. Diet
2. Exercise
3. Age
4. Stress
5. Hormones
Is the gut microbiota relatively insensitive to conditions, or
does it respond quickly to changing conditions? - ---Ans----It
is highly responsive. It changes very quickly to all sorts of
different conditions.
How could you test the effect of a particular host gene on the
gut microbiota? - ---Ans----Use a mouse model where you
could make a knockout of that gene and then see if the
microbiota changed.
How could you test whether a particular microbiotal
composition can affect a host phenotype? - ---Ans----
Transplant the microbiota, isolated from feces, in a germ free
mouse, and assess the phenotype after that microbiota takes
residence in the mouse.
,How is a fecal microbiotal transplant (FMT) achieved? - ---
Ans----Homogenize feces in a sterile buffer, filter it to remove
undigested food structures and solid matter, administer just
the purified bacteria to the recipient.
Name two changes in host factors/behavior that impact that
microbiota such that it can change a host phenotype when
transplanted. - ---Ans----1. Changes in diet (moving from a
high fat, low fiber diet to a low fat, high fiber diet)
2. Changes in circadian rhythm.
How do we initially get our gut microbiome? - ---Ans----We
are inoculated in very early life, especially from our mothers
and from the early foods that we eat.
When does our microbiome transition from the infant-type
microbiome to the adult-type microbiome? - ---Ans----From
ages one to two, as we are weaned.
What is the "bacterial baptism" hypothesis, what practice has it
led to, and why is it contested? - ---Ans----The idea that we
obtain an initially healthy microbiome from our mothers during
the process of vaginal birth. It has led to the idea of vaginal
seeding, where vaginal fluids are wiped onto a baby's face or
body using sterile gauze after the baby is born.
The evidence that bacterial baptism is important has many
confounding factors, so some scientists have urged caution
, around vaginal seeding because it is not fully understood
whether those bacteria are really important.
When is our gut microbiome most important for future health?
- ---Ans----During the first two years of life.
Given the importance of the early microbiome, what is one
practical way that parents can try to guard against harmful
alterations to their child's microbiome? - ---Ans----Parents
can be conservative when using antibiotics. We can also be on
the lookout for ways to restore the microbiome ilike using
probiotics or making diet changes n cases where antibiotics
must be used.
What strategies might future interventions employ to stabilize
and restore the human gut microbiome in a person? - ---Ans-
---Specific diets, probiotic use, or in some cases fecal
microbiotal transfer.
What are three benefits that the gut microbiota provides for a
human host? - ---Ans----1. It helps break down otherwise
indigestible food structures such as cellulose.
2. Production of compounds that promote immune system
development and health.
3. Contributes to glucose homeostasis in our blood.
About how many antibiotic-resistant bacterial infections occur
in the United States each year? How many deaths from such
