Micr 351 Text 4

Front 1

What structural and metabolic characteristics do fungi share that distinguish them from other groups of organisms?

Back 1

the Char: spare spore bearing, absorse nutrition, Lack chlorophyll, reproducse sexually/asexually
Manno Proteins B 1-6, 1-3 Gluccn, phospolipd bilayer, b glucan synthael, chitin polymer, dont require light, decompose organisms.

Front 2

How do fungi obtain nutrients from complex, insoluble molecules?

Back 2

Release hydrolylate enzmyes to break them down.

Front 3

What are some of the major roles that fungi play in the environment?

Back 3

decomposes- make organic molecules available

Front 4

Fungi are commonly divided into two groups based on their morphology: yeasts and molds (aka filamentous fungi). Describe the morphology of each group.

Back 4

Yeast single celled:asexual (budding), sexual(spores),
Molds- filamentous- hyphe, -septae, large surface area

Front 5

Explain the difference between a hypha and a mycelium.

Back 5

Mycelum is a tangled mess of hypha.

Front 6

Describe how the yeast S. cerevisiae divides when growing asexually.

Back 6

buds in all directions budding of ______ hows beings before it's fully budded from perent 4 haploid cells bud to ascus

Front 7

Describe how the filamentous fungus Neurospora crassa grows.

Back 7

Front 8

What are dimorphic fungi? (pg. 632)

Back 8

have 2 major forms can change from yeast form to mold/myccelual in response to stress, called a YM shift

Front 9

What are the major polysaccharides found in fungal cell walls? (Lectures on 11/4/04 and 11/6/09).

Back 9

Mannopreles B-1-6 Glucans and B-1-6Glucans , Chitin(N-acetyglucosamine redisue) glyco-proteins anchor into membrane

Front 10

Bacteria and fungi use a common carrier to deliver cell wall precursors to the enzymes that will polymerize them. What is this carrier?

Back 10

Bactoprenol

Front 11

Many fungi do not have cholesterol in their plasma membranes. What molecule is present instead of cholesterol?

Back 11

ergosterol

Front 12

What are the functions of the vacuole in yeast? (pg. 82, lecture on 11/4/09)

Back 12

temp storage and transit , digestion and water balance

Front 13

Sexual reproduction can occur between fungi of the same species but they have to be different mating types. How do yeast cells signal their mating type?

Back 13

the size, shape, color, # of spores

Front 14

Describe sexual reproduction of the yeast S. cerevisiae.

Back 14

637

Front 15

Most mushrooms belong to the group of fungi called

Back 15

Basidiomycata

Front 16

Fungi that form spores enclosed in a sac-like structure (which is called an ascus) belong to what taxonomic group?

Back 16

Ascomycota

Front 17

What is a general biological reason why there are so few antifungal drugs available for clinical use?

Back 17

They have a unique cell wall that is hard to upset

Front 18

How does the antifungal drug nystatin work? Why does it preferentially act on fungi?

Back 18

chitin synthesis destruction, has chitin

Front 19

What is the target of triazole antifungal drugs, such as fluconazole?

Back 19

~

Front 20

The arbuscular mycorrhizal symbiosis is a symbiosis between what two types of organisms?

Back 20

plant-fungus

Front 21

What nutrient(s) does each symbiotic partner contribute to the other?

Back 21

Gets PO_4_ for plant, plant gives argenic compounds

Front 22

What molecular evidence was used to classify the Microsporidia as fungi?

Back 22

Reclassified using large subunit of RNA Pol. 2 , to transition factors. Beta tubulin, new analysis of ssu rRNA

Front 23

What is the definition of symbiosis, as defined in the textbook?

Back 23

a mutually benificial relationship, as an assiocation of two or more different species of organisms

Front 24

Explain the key difference between mutualistic and cooperative symbiotic interactions.

Back 24

Cooperative is nonobligatory while mutalistic is obligitary

Front 25

Define commensalism and parasitism.

Back 25

Comm: is where one org. is benifitting while the other is neither harmed nor beniffiting

Front 26

Chapter 31 gives several examples of mutualisic and cooperative interactions of microbes with another organism(s). Choose one of these interactions and be able to describe it on Exam 4. You will be expected to name the organisms involved and explain how they benefit one another.

Back 26

Termite-Protozoan : Protozen live in the gut and digest the celluose,they metabolize it to acetate and other products termites oxidize the acetate
Termites(Reticulitemes), Protozen(Trichonympha)

Front 27

What is the total number of microbes living in association with a healthy person? How does the number of microbial cells compare to the number of human cells?

Back 27

Microbial: 10^14
Humans: 10^13

Front 28

What parts of the human body are normally sterile?

Back 28

Internal organs, Bladder(not tip), Peritental cavity, alveoli in lungs

Front 29

, I discussed a study of the diversity of the human skin microbiota. The following questions are about this study.
a) What 3 methods were used to collect samples?
b) How were the bacteria present in each sample identified?
c) What was the total number of bacterial species identified?
d) Most of the species identified belonged to one of four bacterial phyla. What are these phyla?
e) What evidence led the authors to conclude that there is a common skin microbiota shared by many people?

Back 29

a) Sawb, Scrap, Puncture sample
b) Swab68,Scrape55,Punch76
c)sequenced 165- identified 113 different species
d) Firmicuts(gram +), Actinobacteria(High G&C, Gram+, acid fast stain), Bacteroides(Gram-), Proteobacteria(Gram-)
e) Phylogenetic architecture and abundance of OTUs with ≥97% similarity in five human subjects

Front 30

What are potential benefits to the human host of the skin microbiota?

Back 30

They decrease colonization of foregin colonies, compete for binding sites, competes for nutrients, maintains an Acidic pH (Triglyercles--> fatty acids--> pH lower)

Front 31

What does dental plaque consists of?

Back 31

a film of Bacteria on the surface of the teeth

Front 32

In the formation of dental plaque, the early bacterial colonizers do not bind directly to the tooth enamel, but instead bind to the tooth pellicle. What does the tooth pellicle consist of and how is it formed?

Back 32

a layer of acidic glycoproteins from the saliva (SO - , COO-), absorded by enamel, net negative charge repells the bacteria

Front 33

Define Biofilm

Back 33

community of organisms living on a surface

Front 34

Bacteria in a biofilm produce an extracellular matrix that helps attach the organisms in the biofilm to the underlying surface. What macromolecules make up the extracellular matrix?

Back 34

Polysacrides make it up

Front 35

Explain the reasons why bacteria in a biofilm are more resistant to disinfectants and antibiotics than free living bacteria.

Back 35

there is a complex of proteins, glycogens, polysacrides, shere genes, DNA several layers of polymers, tough and to medication

Front 36

Explain the temporal developnment of a typical dental plaque community

Back 36

1 Colonizers- grew w/ saliva as nutrients, fusarium nucleated w/ S.oralus, A.naeslundii
2 :S.mutens and S.subrmus-utalize sucrose -glucose changes to glucons

Front 37

What are the 3 bacterial spices that are common early colonizers of the tooth? how do these organisms adhere to hte surface of the tooth?

Back 37

1)Streptococcus gordonii,
2)S.oralis,
3) S. Mitis
Adhere by specific ionic, Hydraphobic and lictin-like interactions

Front 38

What role do fimbriae playin the formation of dental plaque?

Back 38

they bind to substraits and attack other organisms

Front 39

What metabolic activities of Streptococcus mutans and S. sobrinus contribute to dental decay?

Back 39

Produce extercellular enzymes that polymerize the glucose moiety of sucrose into a heterogeneus group of extercellular ,water-soluble and insoluble glucan polymers and other polysacrides

Front 40

Porphyromonas gingivalis is a Gram-negative bacterium that is associated with gum disease. P. gingivalis doesn't metabolize sugars, what it use as its source of carbon and energy? How does it obtain these compounds when colonizing gum tissues?

Back 40

Requires hemin for Fe2+ and peptides for energy and degrades gums for carbon - uses 5 proteases to satisify this requirenment

Front 41

What are the total numbers of microbes found in the intestinal tract?

Back 41

10^12 gram of net weight

Front 42

Studies comparing germ-free mice with germ-free mice that were inoculated with Bacteroides sp. indicate that microorganisms in the intestinal tract benefit their host. What benefits have been found?

Back 42

Bacteria that help break down nutrients and share them, non-germ mice were small and sickly and weak. digest polysacrides

Front 43

How does the presence of Bacteroides sp. influence the development of the mouse intestinal tract?

Back 43

Doesnt need vitamine supplements

Front 44

what are Peyer's Patches?

Back 44

of lymothode tissue in small intesine with mucus w/ IgA in it the first line of defense against pathogens

Front 45

In what ways does the normal microbiota help to protect against colonization by pathogens?

Back 45

It decreases nutrients, budding sites, acidifys skin

Front 46

Describe the structure of a generic mucous membrane.

Back 46

Epitheial cells covered in a viscous collrd of antimicrobial secretions

Front 47

what is the compsotiton if mucous?

Back 47

Glycoproteins, inorganic ions (suspended in H2O), antimicrobial (lysozmes), lactoferrin(ties up Fe), lactoperoxidase peptides this means it limits the spread of infection

Front 48

What are tight junctions? how does the presence of tight junctions help prevent infection?

Back 48

Tight junctions are protein complexes between cells that prevent the free flow of fluids, microbes, ions from moving freely this means it limits the spread of infection

Front 49

In addition to mucins, which are the predominant protein component of mucus, many mucous secretions contain lysozyme, lactoferrin, and/or lactoperoxidase. What is the activity of each of these enzymes? how does each activity help protect the body against infection?

Back 49

Lysozme- antimicrobial by degredation(acid/bases)
Lactoperoxidase- genes superoxides that damage membranes
Lactoferrin- ties up free Fe2+ needed for lacterial growth

Front 50

Antimicrobial peptides, such as defensins, help prevent infection. What is their mode of action?

Back 50

Circulate in the blood and accomplish intercellular digestion of foregin tissue

Front 51

White blood cells (WBC) in the innate immune system include monocytes, macrophages, dendritic cells, neutrophils, basophils, and eosinophils. For each of these cell types:
a) Are they phagocytic or nonphagocytic?
b) If nonphagocytic, what activity(ies) do they have that help the body resist infection?
c) Where in the body is each cell type usually found?

Back 51

1)Monocytes
a-Phagocytic
b-immature macerophages
c-bloodstream(from bone marrow)

Front 52

2)Macrophages
a-phagocytic(Mononuclecue)
b- -
c-take up residence in specific tissues

Back 52

3)Dendritic- display foregin antiogens-recognice PAMP's, after recogince PDR's pagocytose it , go to the lymph tissue present the antigen to T-cells -trigger immune system
a- Phagocytic
b- -
c-skin/mucus membranes(nose,lungs,intestine)

Front 53

4)Neutrophils
a- Phagocytic(degration using O2 / nonO2 pathways)
b- -
c-Circulate in the blood -rapid migrate to infections

Back 53

5)Basophils(inflmation Responce)
a-nonphagocytic
b-release virus compounds(histamines, )
c-bloodstream

Front 54

What is the relationship between monocytes and macrophages and dendritic cells?

Back 54

Monocytes turn into macrophages and all three

Front 55

What do the acronyms PAMP and PRR stand for?

Back 55

PAMP- Pathogen Assiocated Molecular Pathogens
PRR- Pattern recogintion Receptors