EXAM 4

Question 1

Creating kombucha begins with water, sugar, tea, and microbes (bacteria and yeast). Eventually, the solution turns sour. Determine the purpose of the sugar and describe one technique that you could use to analyze the success of your kombucha.

Answer 1

Sugar speeds up fermentation- compare amount of sugar to amount of bacteria

Question 2

Why is antibiotic-containing soap bad?

Answer 2

It increases the chances of antibiotic resistance

Question 3

How does the Glo-Germ reagent (germ lotion) work from the Contaminated lab?

Answer 3

Lotion represents bacteria, spreads through physical contact

Question 4

Why should we care about microbial control?

Answer 4

Can help to prevent infections and death

Question 5

Static vs. cidal

Answer 5

Static prevent growth, cidal kill microbes

Question 6

Know how to determine D-value from a data table

Answer 6

Look for 90% reduction in organism count

Question 7

When should flame be used to sterilize something?

Answer 7

Not heat sensitive

Question 8

Cause and consequences of thymine dimers

Answer 8

From thymine and cytosine bases, bind together as a result of UV damage

Question 9

Disinfectants vs. antiseptics

Answer 9

Disinfectant- Destroy microbes
Antiseptic- Destroy microbes or inhibit growth, used on living tissue

Question 10

Know how to determine thermal death point from a data table

Answer 10

Lowest temperature that kills all population after 10 minutes

Question 11

How to sterilize a vitamin solution that is sensitive to heat/light

Answer 11

Filtration

Question 12

Know how to determine MIC if given a graph

Answer 12

Lowest concentration of a drug that kills microbes

Question 13

Roles of copper, silver, mercury, and zinc in microbial control (heavy metals)

Answer 13

Can induce oxidative damage

Question 14

Roles of iodine vs. fluoride vs. chlorine in microbial control (halogens)

Answer 14

Iodine- Penetrates cell walls, used as antiseptic on skin
Fluoride- Reduces acid tolerance of bacteria, used in water to prevent tooth decay
Chlorine- Removes biofilms, used in water

Question 15

Know which antiseptic compound is most likely found in mouthwash

Answer 15

Chlorhexidine

Question 16

Purpose of in-use test for disinfectants

Answer 16

Tests to make sure it still works

Question 17

Benefits of yogurt, probiotics, and enhanced gut microbial diversity

Answer 17

Yogurt is fortified with bacteria, allows for microbiome diversity

Question 18

Roles of the different SCFAs (butyrate, propionate, acetate)

Answer 18

Short chain fatty acids- anti inflammatory properties, antimicrobial, gut homeostasis

Question 19

Negative effects of low gut microbial diversity and artificial sweeteners

Answer 19

Autoimmune diseases, cancer, worse mental health

Question 20

How to change your gut microbiome

Answer 20

Diet, antibiotics, probiotics

Question 21

Types of hemolysis and the organisms associated with them

Answer 21

Beta: Complete lysis of RBC, streptococci
Alpha: Lysis of hemoglobin, pneumonia, streptococcus mitis
Gamma: No destruction, enterococcus faecalis

Question 22

Roles of Streptococcus mutans in dental health

Answer 22

Linked to tooth decay

Question 23

Roles of Fusobacterium nucleatum in cancer

Answer 23

Linked to colorectal cancer

Question 24

Roles of Porphyromonas gingivalis in Alzheimer’s disease

Answer 24

High levels linked to alzheimer’s

Question 25

Causative links between the gut microbiota and major depressive disorder

Answer 25

Dialister, Faecalibacterium and Coprococcus are linked to better mental health

Question 26

Alpha hemolysis on blood agar

Answer 26

Greenish discoloration, Streptococcus pneumonia

Question 27

Beta hemolysis on blood agar

Answer 27

Clear zone, Streptococcus pyogenes

Question 28

Gamma hemolysis on blood agar

Answer 28

Partial decomposition of hemoglobin, like alpha but milder, Enterococcus faecalis.

Question 29

Louis Pasteur

Answer 29

lactic acid (fermentation) inhibited pathogens

Question 30

Relative abundance of microbes in the gut

Question 31

There are four possible mechanisms by which gut bacteria may influence the brain. Describe one of them in detail and describe how it may be related to a specific mental health condition.

Answer 31

Gut bacteria may produce neurotransmitters, which antidepressants work to produce

Question 32

In 1899, Henri Tessier discovered

Answer 32

breastfed infants had Bifidobacterium bifidum in their gut

Question 33

In 1905, Stamen Grigorov discovered

Answer 33

Lactobacillus bulgaricus (yogurt production)

Question 34

Elie Metchnikov promoted the use of fermented dairy to

Answer 34

slow down aging

Question 35

Stomach and duodenum

Answer 35

10^1-10^2/ml

Question 36

Colon

Answer 36

10^10-10^12/ml

Question 37

Jejunum and ileum

Answer 37

10^4-10^5