CPA #1 Questions

Question 1

What microscope has the greatest resolving power & why?

Answer 1

electron microscope because electrons have shorter wavelengths

Question 2

Is a larger or smaller resolution distance preferred & why?

Answer 2

smaller; smaller resolution = greater magnification = greater power

Question 3

what is the purpose of a cell wall?

Answer 3

provide structure and shape to cell; protects from osmotic forces; assist in attaching to other cells; resist antimicrobial drugs

Question 4

Do animal cells have cell walls?

Answer 4

no

Question 5

Compare/contrast endospores to reproductive spores

Answer 5

Endospores are durable + potentially pathogenic; one single vegetative cell turns into only one single endospore; endospores are the defensive strategy for bacteria in extremely harsh conditions.

reproductive spores are used for reproduction of fungi, actinobacteria, and algae.

Question 6

which is more concerning: an infection from a gram+ or gram- bacterium?

Answer 6

gram - negative due to the presence of lipid A, which is toxic/ deadly. Dead gram- cells release lipid A when the outer membrane disintegrates.

Question 7

what is lipid A?

Answer 7

lipid A is the lipid portion of LPS (lipopolysaccharide). LPS is a union of lipid with sugar.

Question 8

what conditions can an endospore survive?

Answer 8

resistant to drying, extreme heat, extreme radiation, and lethal chemicals.

Question 9

why are endospores so concerning in the medical field?

Answer 9

they are resistant to tratments that inhibit other microbes; endospore-forming bacteria produce deadly toxins that cause fatal diseases (anthrax, tetanus, gangrene)

Question 10

list 4 ways the skin helps the body

Answer 10

1. prevents excessive water loss
2. regulates body temp (sweating/ vasodilation/ vasoconstriction)
3. helps form vitamin D
4. involved in sensory phenomena

Question 11

does the body contain normal helpful microbes? why?

Answer 11

yes; they protect the skin by competing with potential pathogens for nutrients and space + produce chemicals that interfere with other microbe growth.

Question 12

why are there few microbes on the skin?

Answer 12

inhospitable environment; sweat + sebum prevent growth of many organisms

Question 13

why does an odor come from armpits?

Answer 13

organisms of human microbiome usually grow where conditions are moist (groin/armpits) and their waste products produce odor.

Question 14

what is the most salt tolerant bacteria found on skin?

Answer 14

staphylococcus epidermis

Question 15

what are the 5 general types of organisms that can cause skin diseases?

Answer 15

1. bacteria
2. viruses
3. protozoa
4. fungi
5. arthropods (arachnids + insects)