Normal Flora

Question 1

What is normal flora?

Answer 1

normal flora is a mixture of organisms regularly found associated with the body.

Question 2

Give examples of areas of the human body that are sterile.

Answer 2

lungs, heart, liver, kidneys, bladder, muscles, and brain.

Question 3

Commensalism

Answer 3

one organism benefits and the other is neither helped nor harmed (neutral).

Question 4

Parasitism

Answer 4

one organism benefits and other is harmed.

Question 5

Mutualism

Answer 5

both organism benefit.

Question 6

How do normal microbiota benefit human hosts? What are the 3 ways in which they exclude potential pathogens?

Answer 6

• Normal microbiota benefit human hosts from nutrients, immune system stimulation (a training system for our immune system and introducing microbes in our immune system), and exclusion of potential pathogens.
• Three ways in which the host exclude potential pathogens: microbiota compete with pathogens for space.

Question 7

What benefits of normal microbiota derive from their host?

Answer 7

the benefits that normal microbiota derive from their host are nutrients, stable environment, and easy transport from one person to another.

Question 8

What is tissue tropism?

Answer 8

• Tissue tropism is the ability of a given pathogen to infect a specific location.
• Bacteria prefer certain tissue over others and tissues provide essential growth factors.

Question 9

What enzyme produced by H. pylori enables this microbe to grow in the stomach environment?

Answer 9

Urease is the enzyme that is produced by H. Pylori, which enables microbes to growth in the environment. Urease makes the stomach acid less acidic.

Question 10

What are some reasons for a change/ difference in normal flora within the oral cavity and GI tract of babies and toddlers?

Answer 10

The oral cavity is sterile at birth as the baby is still in the mother womb shield from microbes, but when the baby is delivered the microbiota are established either through vaginal birth or through c-section and bacteria colonize after first feeding. GI tract through breast feeding Bifidobacterium spp is introduced and changes after babies switch to solid food/cow’s milk. As babies and toddlers they are still being introduced to new microbiota which can either be found through food and other things.

Question 11

What are benefits and limitations of probiotics?

Question 12

What parts of the genitourinary tract are colonized by normal flora?

Question 13

Are normal flora found in both the upper and lower respiratory tract? Explain your answer.