Block D Part 4: Our Microbiome

Question 1

What is a microbiome?

Answer 1

A functional collection of all microbes in a particular environment
(Lecture 4, Slide 3)

Question 2

What 3 things do gut microbes help with?

Answer 2

Digesting food, synthesizing vitamins and influencing the development and efficiency of our immune system
(Lecture 4, Slide 4)

Question 3

What does akkermansia muciniphila do?

Answer 3

Promotes host tissue differentiation by causing continuous regeneration of the protective mucin layer
(Lecture 4, Slide 4)

Question 4

What does Bacteroides thetaiotamicron do?

Answer 4

Breaks down complex carbohydrates into products that can be absorbed by the body
(Lecture 4, Slide 4)

Question 5

What are 3 things that make it difficult for microbes to colonize our skin?

Answer 5

Dry
Salty
Acidic
Protective oils
Sweat includes fatty acids which inhibit growth of some microbes
(Lecture 4, Slide 10)

Question 6

What were the lungs and trachea originally thought to be?

Answer 6

Sterile
(Lecture 4, Slide 12)

Question 7

What 3 parts make up the mucociliary escalator?

Answer 7

The ciliated (small hair structures lining it) lining of the trachea, bronchi and bronchioles
(Lecture 4, Slide 12)

Question 8

What does the mucociliary escalator do?

Answer 8

Sweeps foreign particles up and out of the lung
(Lecture 4, Slide 12)

Question 9

Which words describes the microbes in the lungs, trachea and genitourinary tract?

Answer 9

Transiently (only passing through)
(Lecture 4, Slide 13)

Question 10

When does vaginal microbiota change?

Answer 10

Over a woman’s lifetime and during the menstrual cycle
(Lecture 4, Slide 13)

Question 11

Why do few microbes survive in the stomach?

Answer 11

Due to the low pH
(Lecture 4, Slide 14)

Question 12

What can gut microbes produce?

Answer 12

Metabolites
(Lecture 4, Slide 14)

Question 13

Are lower gastrointestinal tract microbes mostly aerobic or anaerobic?

Answer 13

Anaerobic
(Lecture 4, Slide 15)

Question 14

What does the gastrointestinal tract microbiome do?

Answer 14

It helps to protect against pathogens
(Lecture 4, Slide 16)

Question 15

What can the accidental penetration of certain organisms beyond a site of colonization cause?

Answer 15

Infections
(Lecture 4, Slide 18)

Question 16

What can lead to inflammation and disease?

Answer 16

Unsettling the homeostasis of our microbiome
(Lecture 4, Slide 18)

Question 17

What are 2 diseases associated with microbes normally present in our microbiome?

Answer 17

Caries
Periodontitis
Acne
Inflammatory bowel disease (IBD)
Vaginitis (inflammation of the vagina)
(Lecture 4, Slide 19)

Question 18

What are 3 things that can cause obesity?

Answer 18

Complex interactions among genes, diet and a long-term imbalance between energy intake and expenditure
(Lecture 4, Slide 20)

Question 19

What do studies from Jeffery Gordon’s lab show?

Answer 19

A link between obesity in humans and their microbiomes
(Lecture 4, Slide 20)

Question 20

What are the 2 major ways in which microbiota can influence obesity?

Answer 20

Harvesting energy from ingested food
Triggering intestinal inflammation
(Lecture 4, Slide 21)

Question 21

What can intestinal microbes do and what do they produce doing this?

Answer 21

Ingest many foods that we cannot, producing short-chain fatty acids (SCFAs)
(Lecture 4, Slide 21)

Question 22

What can the amounts and ratios of short-chain fatty acids (SCFAs) influence?

Answer 22

Obesity
(Lecture 4, Slide 21)

Question 23

What does lipopolysaccharide (LPS) produced by gram-negative species promote?

Answer 23

Inflammation
(Lecture 4, Slide 21)

Question 24

What can a high-fat diet promote?

Answer 24

Absorption of lipopolysaccharide (LPS) across the intestinal epithelium
(Lecture 4, Slide 21)

Question 25

What are 2 things that can modulate our microbiome?

Answer 25

Probiotics (food or supplements that contain live microorganisms)
Prebiotics (food that acts as food for human microflora)
Faecal transplants
Possibly personalised medicine
(Lecture 4, Slide 22)