MICR 4423 ACTUAL EXAM 5 QUESTIONS WITH

MICR 4423 (ACTUAL / ) 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

• Exercise
• Age
• Stress
• 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.

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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)

• 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 2 / 3

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.

• Production of compounds that promote immune system

development and health.

• 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

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