MICROBIOLOGY

Question 1

what is an infectious disease

Answer 1

disease caused by microbial invasion/multiplication

Question 2

what is the difference between a communicable disease and a contagious disease

Answer 2

communicable disease is an infectious disease that spreads through a path e.g. through water whereas contagious disease is one that passes between hosts

Question 3

what is the 5 kingdoms of classification in order

Answer 3

kingdom-phylum-class-order-family-genus-species ( KING PHILIP CAME OVER FOR GOOD SOUP)

Question 4

whats the difference between a prokaryote and eukaryote

Answer 4

prokaryote is unicellular while eukaryotes are multicellular

Question 5

whats the difference in structure between prokaryote and eukaryote

Answer 5

• prokaryotes are smaller than eukaryotes
• prokaryotes have no carbohydrates and lacks sterols whereas eukaryotes have both
• prokaryotes have 50s and 30s subunits whereas eukaryotes have 60s and 40s subunits
• prokaryotes have 1 chromosome free floating and eukaryotes have multiple chromosomes

Question 6

what are the different shapes of bacteria (six of them)

Answer 6

bacilli-rod
cocci-shpere
ovococci-oval
spirrilum- spiral
vibrio-comma
spirochaetes-zig zag

Question 7

what are the names of different arrangement

Answer 7

chains of cooci-streptococcus spp
clusters of cocci-staphylococcus
pair of cocci/diplococci-streptococcus pneumoniae

Question 8

what is a bacterial capsule made of

Answer 8

polysaccharide

Question 9

what is the purpose of the bacterial capsule

Answer 9

for immune resistance/evasion

Question 10

what are the layers of the exoskeleton(outside to inside)

Answer 10

endoflagella-axial filament-cell membrane-periplasmic space

Question 11

what is the cell wall made of

Answer 11

sugars linked by a small amino acid chain

N-acetyl-glucosamine and N-acetyl-muramic acid

Question 12

whats the purpose of a cell wall

Answer 12

• cell shape determines growth,motility/reproduction
• restricts the transit of large molecules
• resistance to osmotic pressure
• aids in immune evasion
• assembly of proteins with various functions

Question 13

whats the difference between gram positive and gram negative

Answer 13

gram positive has a thick peptidoglycan cell wall and a single layer underneath whereas the gram negative has a thin peptidoglycan cell wall and has two layers and has an outer lipposaccharide layer

Question 14

what features do bacteria have

Answer 14

flagellum-to swim

fimbriae/pilus-for attachment to surfaces

Question 15

what is a virus structure

Answer 15

it is acellular and has no metabolic capability

Question 16

where does it get its energy

Answer 16

from harnessing the molecular machinery of the host cell

Question 17

what kind of parasite is a virus

Answer 17

non-cellular obligate (needs a host)

Question 18

how is the shape of a virus decided

Answer 18

by its protein caspid which also protects the genetic materials inside

Question 19

what is the life cycle of a virus

Answer 19

adsorption-penetration-uncoating-early transcription-early translation-dna synthesis and late transcription-late translation-condensation-assembly-release

Question 20

describe the process of the virus infection

Answer 20

first the viral capsid enters the cells nucleus and then there is synthesis of early mRNA which then synthesises proteins such as DNA polymerase. then the viral DNA and late mRNA leads to synthesis of late proteins such as capsid proteins which then enter the nucleus and the viral capsids are then released and they then invade other cells

Question 21

how does fungi grow

Answer 21

binary fission

Question 22

what is a fungal cell wall made of

Answer 22

chitin based- N-acetylglucosamine homopolymer

Question 23

how does the fungal cell wall fold

Answer 23

it folds on itself enabling hydrogen bonds to form and it often binds to beta 1-3 glucan that anchors proteins

Question 24

what is the fungal membrane made of

Answer 24

ergosterol

Question 25

in what environment is it typically comfortable growing in

Answer 25

pH 5 , low moisture , at high osmotic pressure (lots of sugar and salt)

Question 26

features of the protista/eukaryotes

Answer 26

unicellular eukaryotes and can ingest complex food particles through the cytostome

Question 27

how do Protozoa move

Answer 27

amebas-move by extending cytoplasmic projections flagellates-move by rotating whip like flagella ciliates-move by synchronous beating of hair like cilia sporozoa-generally non mobile

Question 28

what are the stages of protozoa growth cycle

Answer 28

cyst-resistance stage thickened cell wall trophozite-stage that actively feeds and multiples flagellated-temporary non feeding stage

Question 29

what is the name for parasitic worms and what are the two main categories

Answer 29

helminths divided into plathelminthes/flatworms (flat and have no true body cavity) and nemathelminthes/roundworms (worm like, separate sex, unsegmented roundworms)

Question 30

what are the different classes of flatworms

Answer 30

Cestoda/tapeworms and Trematoda/flukes

Question 31

what causes pityriasis/tinea versicolor

Answer 31

malasezia furfur, typical skin microbiota

Question 32

what are the symptoms and affected areas

Answer 32

- scaly discoloured skin patches - sometimes itchy - affects the chest, back and neck

Question 33

what color does gram positive and negative stain

Answer 33

positive-purple | negative-red

Question 34

what are the stages of bacterial growth

Answer 34

lag phase-adaptation to new environment log phase-adapted and optimal conditions for growth stationary phase-nutrients become compromised and toxic waste accumulates death phase-nutrients depleted and toxic waste leads to death

Question 35

name the 5 names of bacteria in terms of their optimum temperature from lowest to highest temp

Answer 35

psycrophiles, psychrotrophs, mesophiles, thermophiles, hyperthermophiles

Question 36

name the 5 names of bacteria in terms of their optimum pH in terms of lowest pH to highest pH

Answer 36

extreme acidophiles, acidophiles, neutrophiles, alkalophiles, extreme alkalophiles

Question 37

what is the pH range for each category of the bacteria

Answer 37

``` extreme acidophiles- 0-2 acidophiles- 2-5 neutrophiles- 6-8 alkalophiles- 9-12 extreme alkalophiles-12-14 ```

Question 38

what are the different types of medium

Answer 38

general (non selective) - contains nutrients for growth of a large of bacteria selective - contains nutrients for growth of selected organisms differential - contains nutrients that enable growth and differentiation of various organisms

Question 39

what's the difference between microbiota and microflora

Answer 39

they're the same but microflora is the old term

Question 40

what's the difference between microbiota, microbiome and metagenome

Answer 40

the microbiota have a taxonomic classification eg culture, biochemistry metagenome is the collection of genomes and genes from the members of a microbiota microbiome includes all the microorganisms, their genomes and bionic and abiotic factors- basically is the environment

Question 41

how do microbiota benefit the immune system

Answer 41

exposure of T regulatory cells to intestinal microbes decreases the reactions to self antigens as well as non harmful pathogens

Question 42

how are microbiota a source of essential nutrients

Answer 42

extract nutrients from undigested carbohydrates and aids in maintenance of pH

Question 43

an example of healthy bacteria on the surface of our skin

Answer 43

staphylococcus epidermidis

Question 44

which bacteria is the most common bacteria responsible for skin and soft tissue infections

Answer 44

staphylococcus aureus

Question 45

which environment does staphylococcus grow better in

Answer 45

moist and higher pH

Question 46

which other bacteria grow in moist conditions

Answer 46

corynebacteria and candida spp

Question 47

which area supports anaerobic organisms on the body

Answer 47

the hair follicles and sebaceous glands for propionibacterium acnes

Question 48

which bacteria makes up 90% of the bacteria in your mouth

Answer 48

streptococcus spp

Question 49

what are other examples of bacteria in your mouth

Answer 49

gemella spp, granulicatella spp, velionella spp

Question 50

whats the distribution of gram positive and gram negative between rural Africa and Europe

Answer 50

rural Africa has more gram positive than Europe and Europe has more gram negative than rural Africa

Question 51

what is mycobiology referring to

Answer 51

fungi

Question 52

what type of fungi is present in wet areas

Answer 52

candida leads to candidiasis

Question 53

what type of fungi is present in dry areas

Answer 53

malasezzia leads to pityriasis

Question 54

what type of fungi is present in dry and acidic areas

Answer 54

aspergillum leads to aspergillosis

Question 55

which bacteria makes up most of the bacteria in the gut

Answer 55

bacteroidetes

Question 56

which of the two bacteria do you have in the vagina( can't be present together)

Answer 56

prevotella or lactobacillus

Question 57

which of the two bacteria do you have on the skin ( can't be present together )

Answer 57

propionibacterium or staphylococcus

Question 58

which of the two bacteria can you have in your mouth ( can't be together )

Answer 58

streptococcus or tanerella

Question 59

what happens in GI tract disorders

Answer 59

the patients exhibit decreased microbial population and functional diversity which is decreases firmicutes and increased bacteroidetes

Question 60

what happens in metabolic disorder

Answer 60

increase in firmicutes and decrease in bacteroidetes

Question 61

what is dysbiosis

Answer 61

when there is a misbalance between the microbiota in the human gut leading to illness

Question 62

what is the path to dysbiosis

Answer 62

commensal microbiota -- changes intestinal micro biome-- vulnerable to pathogens--inflammation and mucosal tissue damage-- predisposes to pathologies -- colonization factors ( toxins) e.g. chrones disease

Question 63

what type of bacteria are proteobacteria

Answer 63

gram negative

Question 64

what type of bacteria are firmicutes

Answer 64

gram postive

Question 65

what group of bacteria are pseudomonas aeruginosa, escheria coli

Answer 65

proteobacteria

Question 66

what group of bacteria are staphylococcus aureus, staphylococcus epidermidis, streptococcus oralis

Answer 66

firmicutes

Question 67

which type of environment is propionibacterium most commonly found

Answer 67

sebaceous sites

Question 68

what type of site is corynebacteria most commonly found

Answer 68

moist sites

Question 69

what type of site is staphylococcus most commonly found

Answer 69

moist sites

Question 70

what type of site is proteobaceria most commonly found

Answer 70

dry sites

Question 71

what type of site is bacteroidetes most commonly found

Answer 71

dry sites

Question 72

what conditions are linked to skin dysbiosis

Answer 72

acne, psoriasis, atopic dermatitis and rosacea

Question 73

what bacteria is most likely to cause atopic dermatitis

Answer 73

staphylococcus

Question 74

where is regIII gamma (C-type lectin) expressed

Answer 74

skin lesions of psoriasis

Question 75

what is the function of regIII gamma

Answer 75

it is an antimicrobial ad regulates proliferation and differentiation of keratinocytes to promote wound healing

Question 76

what type of bacteria produces regIII gamma

Answer 76

gram negative through peptidoglycan and flagellin

Question 77

what is the relationship between antibiotic treatment and regIII gamma production

Answer 77

as antibiotic increases the production of regIII gamma decreases