CPA #2 Questions

Question 1

why is it important to classify organisms?

Answer 1

bring sense of order/ organization; to enhance communication; to make predictions about the structure and function of similar organisms; to understand evolutionary connections

Question 2

what are the 5 kingdoms?

Answer 2

1. Animalia
2. plantae
3. fungi
4. protista
5. prokaryotae

Question 3

what are the 3 domains?

Answer 3

1. eukarya
2. bacteria
3. archaea

Question 4

what is the difference between prokaryotes and eukaryotes?

Answer 4

domain eukarya contain nucleus;
domains bacteria and archaea do NOT contain nucleus

Question 5

what are the 5 types of information used to differentiate microbes?

Answer 5

1. physical characteristics
2. biochemical tests
3. serological tests
4. phage typing
5. analysis of nucleic acids

Question 6

differentiate microbes using the sequence of nucleotides in nucleic acid molecules

Answer 6

analysis of nucleic acids

Question 7

differentiate microbes using phages, which are unique and specific to the host

Answer 7

phage typing

Question 8

differentiate using antigen-antibody testing

Answer 8

serological tests

Question 9

differentiate microbes using the differences in microbe ability to utilize or produce certain chemicals

Answer 9

biochemical tests

Question 10

differentiate microbes based solely on their morphology

Answer 10

physical characteristics

Question 11

what is microbial antagonism?

Answer 11

normal microbiota use nutrients, take up space, release toxic waste products, which make it less likely for arriving pathogens to become established + produce diseases.

Question 12

is microbial antagonism good or bad? why?

Answer 12

good; under normal circumstances it is good because it reduces likelihood of pathogens to produce diseases

Question 13

what are the 3 key elements of microbial antagonism?

Answer 13

1. take up space
2. take up nutrients
3. change pH in area

Question 14

define zoonoses

Answer 14

diseases that spread naturally from animal to human

Question 15

why are humans dead-end hosts for zoonotic pathogens?

Answer 15

humans are not significant reservoirs for the reinfection of animal hosts; animals do not often eat humans and animals have less common contact with human waste

Question 16

can an asymptomatic human carrier be infectious?

Answer 16

yes; some carriers incubate pathogen and eventually develop the disease, others remain a continued source of infection without ever getting sick.

Question 17

how do adhesion factors determine host specificity?

Answer 17

specific interactions of adhesions and receptors with chemicals on host cells

Question 18

define biofilm

Answer 18

pathogens that attach to each other to form a sticky web of bacteria and polysaccharides which adheres to a surface

Question 19

what is an example of a biofilm?

Answer 19

dental plaque

Question 20

define contamination

Answer 20

contact with the pathogen

Question 21

define infection from contamination

Answer 21

pathogen is able to gain access to body (skin break, etc)

Question 22

define disease from contamination

Answer 22

multiplication of pathogen resulting in adverse conditions

Question 23

define symptom

Answer 23

subjective characteristics; felt by patient

Question 24

define sign

Answer 24

objective characteristics; observed or measured by others

Question 25

define syndrome

Answer 25

group of symptoms and signs that collectively characterize a particular disease

Question 26

define sequela

Answer 26

a condition which is the result of previous injury or disease

Question 27

why are subclinical infections so hard to treat?

Answer 27

they lack symptoms so they go unnoticed; patient feels fine, but there may be signs; asymptomatic

Question 28

what is the purpose of Koch’s Postulates?

Answer 28

to prove that a given infectious agent causes a given disease

Question 29

what are Koch’s 4 Postulates

Answer 29

1. the suspected agent present in every case of the disease.
2. that agent must be isolated and grown in pure culture
3. the cultured agent must cause the disease when inoculated into healthy susceptible experimental host
4. the same specimen should be found in the diseased experimental host

Question 30

why can’t Koch’s postulates always be used

Answer 30

some pathogens have never been cultured; some diseases are caused by combination of pathogens; ethical reasons

Question 31

what areas of digestive system are normal microbes found?

Answer 31

tongue, teeth, jejunum, ileum, colon, rectum

Question 32

what areas of digestive system are axenic (no microbes)?

Answer 32

esophagus, stomach, duodenum

Question 33

how do intestinal microbes protect the body?

Answer 33

outcompeting pathogens (microbial antagonism); produce vitamin B12, folic acid, biotin, vitamin K, daily flatus

Question 34

how can oral antimicrobials affect these normal microbes?

Answer 34

inhibit intestinal microbiota, undermining defensive properties; long term loss can allow colonization of pathogenic microbes.