Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

I&I > Microbiology: A Focus on Bacteria, Fungi, and Viruses > Flashcards

Microbiology: A Focus on Bacteria, Fungi, and Viruses Flashcards

1
Q

How do “bad” pathogens arise from human microbiome

A

dietary changes
stress
antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

True/false: Majority of pathogens are non-pathogenic

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do pathogens do to help them survive?

A

They constantly evolve by either losing or gaining traits over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the incubation period

A

The time it takes the pathogen to enter the body and show the first symptom to appear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the incubation period depend on

A

health of host
growth rate of pathogen
degree of exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the timeline of infection

A

incubation period –> onset of illness –> period of invasion –> convalescent period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the different types of infections

A

Acute
Chronic
Latent (persistent)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is an acute infection

A

Symptoms develop quick
Clears quickly
Host has immunity for reinfection
ex. strep throat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is chronic infection

A

Symptoms develop slowly
Can last months to years
ex. tuberculosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is latent (persistent) infection

A

Illness never goes away
It becomes formant in the body and can be awakened with low immunity
ex. syphilis, typhoid, fever, etc.

Carriers: the host may not show symptoms but they spread it to others

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is horizontal transmisson

A

person to person (horizontal)
ex. blood, saliva, stds, urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is vertical transmissoin

A

Mother to baby via breast milk, delivery, placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a vector

A

An animal or arthropod that caries a pathogen and can transfer it to humans
ex. rabies virus transmitted by animal bite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is virulence?

A

the degree of pathogenicity of a pathogen (bacteria, fungi, or virus) and is determined by its ability to invade and multiply within the host causing disease

They grow and thrive at the expense of the host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is a strict pathogen

A

always causes disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an opportunistic pathogen

A

part of normal microbial flora
takes advantage of a weakened immune system
caused by the disruption in the microbial flora
breached barrier introduced by a wound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Bacterial Characteristics shapes

A

Maintained by cell wall of bacteria composed of peptidoglycan

No nucleus –> chromosome forms a structure called a nucleoid

No membrane-bound organelles (prokaryotic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the main shapes of bacteria

A

cocci
bacilli
spiral
pleomorphic (no defined shape)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the cocci shape

A

Spherical bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the different variations of cocci?

A

Single organisms (cocci)
Pairs (diplococcus)
Chains (streptococcus)
Clusters (staphylococcus)
Tetrads
Sarcina (cube of eight cocci)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is bacilli

A

Rod shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the variations of bacilli

A

Single (bacilli)
Double (diplobacilli)
Chain (streptobacili)
Palisades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the intermediate shape between coccus and a bacillus

A

coccobacilli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the shapes of spiral bacteria

A

Vibrio
Spirillum
Spriochete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is vibrio

A

curved or comma-shaped rod

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is spirllum

A

Thick, rigid spiral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is spirochete

A

thin, flexible spiral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is pleomorphic

A

do not have any characteristic shape
can change their shape
also can be a combination of shapes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What cell retains crystal violet from iodine

A

gram +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What cell does not retain crystal violet and appears transparent

A

gram -

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which cell has a thick multi-layered peptidoglycan layer

A

gram +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Which cell structure contains lps

A

gram -

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is LPS

A

only produced by gram (-)
Consists of lipid and carbohydrate
Helps bacteria cause disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are cell wall components

A

LPS (only in gram -) and peptidoglycan (sugar and amino acids)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

which cell type has an outer membrane that prevents crystal violet penetration

A

gram (-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Which cell develops resistance more quickly

A

gram (-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Which cell is more resistant to antibodies due to impenetrable cell wall

A

gram (-)

38
Q

Which cell lacks peptidoglycan

A

gram (-)

39
Q

What are acidophiles

A

bacteria that grow optimally at pH values around 2

40
Q

What are alkalophiles

A

only grow well at pH values near 10

41
Q

Aciduric (acid tolerant)

A

Can survive acidic conditions but not necessarily grow under those conditions

42
Q

Psychrophiles

A

Prokaryotes that grow very poorly at temperatures above 15 celcius

43
Q

Thermophiles

A

thrive at 100 degrees C

44
Q

What are the components of a bacterial cell structure

A

Capsule
Cell wall
Cytoplasmic membrane
Pili
Flagella
Nucleoid
Cytoplasm
Ribosomes

45
Q

What is capsule

A

covers the outer layer of the cell wall
composed of polysaccharides
mediates attachment of bacterium to host tissues
can inhibit phagocytosis by neutrophils and macrophages –> virulence factor for some bacteria

46
Q

Strep mutans

A

one of the causative agents of dental caries
attaches to tooth surfaces via a capsule

47
Q

What is slime layer

A

some bacteria have a loosely adherent colloidal material that they secrete

usually similar to the capsule

48
Q

What is a pili (aka fimbriae)

A

Extend from cell surface
Pili: long hair-like tubular microfibers
Responsible for: attachment and transfer of DNA & motility

only in gram (-) only!!

49
Q

What is the flagella

A

extend from interior cell body
Responsible for: motility, also sense certain temperature and chemicals/metals

present in both gram + and -

50
Q

Bacterial Growth Curve phases

A

lag phase –> exponential (log) phase –> stationary phase –> death phase

51
Q

What is the lag phase

A

initial phase characterized by cellular activity BUT NOT GROWTH

cells increase in size, but no cell division

52
Q

Exponential (log) phase

A

cells divide by binary fissions & metabolic activity high

53
Q

Which bacteria growth phase are antibiotics and disinfectants most effective in?

A

Exponential (log) phase

54
Q

Stationary phase

A

Bacterial cell growth reach a plateau

Number of dividing cells equal the number of dying cells

No overall population growth

55
Q

Death phase

A

Number of living cells decreases exponentially

Population growth experiences sharp decline

56
Q

Bacterial spores

A

gram (+) bacteria only form spores
especially under adverse environmental conditions

57
Q

What is the importance of spores

A

structure of spore protects its DNA from intense heat, radiation, and attack by most enzymes and chemical agents

So resistance to environmental factors –> can exist for centuries

Difficult to decontaminate with standard disinfectants or autoclaving

58
Q

Aerobic bacteria

A

require oxygen for basic survival, growth, and reproduction

59
Q

Anaerobic

A

don’t require oxygen for growth

60
Q

Fermentation

A

Anaerobic conditions only

Conversion of pyruvate to various end products (ethanol and lactic acids)

61
Q

True/false: aerobic and anaerobic conditions both involve glycolysis

A

True

62
Q

Which cell has peptidoglycan and what does peptidoglycan do

A

gram (+)
Induce fever/inflammation

63
Q

What does LPS do? (low vs. high doses)

A

Low doses: activates immune response and triggers fever

High doses: extreme fevers, septic shock, skin lesions (fatal)

64
Q

Two ways bacteria cause disease

A

release of exotoxins
bacteria inhibit phagocytosis of immune cells

65
Q

release of exotoxins (polypeptides)

A

receptor-binding proteins that cause cell death or change in function

Cytolysis bursting of host cell from osmotic pressure

66
Q

What type of bacteria releases exotoxins

A

gram - and gram +

67
Q

What do exotoxins do

A

releases: enzymes, gas, acids, toxins

toxins: cause cell lysis and can cause degradation of tissue by immune response

Can be encoded on a plasmid or a bacteriophage

68
Q

Transformation

A

introduction, uptake and expression of foreign genetic material

69
Q

Conjugation

A

Transfer of DNA via plasmid from a donor cell to a recipient cell

Involves pilius

70
Q

Transduction

A

bacterial DNA is moved from one bacterium to another by a virus

71
Q

Quorum sensing

A

bacteria’s way to communicate

72
Q

Fungi

A

diverse group of free-living eukaryotic micro organnisms
may be unicellular or multicellular

73
Q

Fungi in our body

A

controlled by competent immune system and multiplies when conditions are favorable

74
Q

obligate intracellular parasites

A

viruses

75
Q

Are viruses alive

A

me dont think so because”
do not reproduce, do not maintain metabolism to gain energy on their own

76
Q

Different virus structures

A

Naked capsid virus or enveloped virus

77
Q

What is naked capsid virus (non-enveloped)

A

typically more virulent
usually cause host cell lysis
cell lysis= most common exit mode from host cell
Does not have extra lipid membrane

Antibodies are generally sufficient for protection against these infections

78
Q

True/false: Non-enveloped capsid virus is more resistant to extreme pH, heat, dryness, and simple disinfectants

A

true yuhh

79
Q

How does naked capsid virus spread

A

spread on fomites, hand to hand, and by small droplets

80
Q

Where can naked capsid virus grow

A

can survive in the gastrointestinal system because of their resistance to low pH and bile detergents

81
Q

Characteristics of enveloped virus

A

typically less virulent

don’t always cause cell lysis during cell exit

contain an outer membrane that surrounds the capsid –> can use host cell membrane itself to assemble their membrane –> process avoids cell lysis and helps enveloped viruses escape from host’s immune system

82
Q

Which type of virus is relatively less sensitive to environmental conditions

A

enveloped virus

83
Q

what virus can spread in large droplets and secretions or by organ transplantation and blood transfusion

A

enveloped virus

84
Q

Virus classification is based on

A

size, morphology, nucleic acid, disease they cause, means of transmission

85
Q

Morphology of a virus is based on

A

size and shape

86
Q

Chemical composition and mode of replication

A

may consist of DNA or RNA
may be single or double stranded
may be linear or circular

87
Q

Characteristics of DNA viruses

A

mostly double stranded
replication occurs in the nucleus
has to be transcribed prior to being synthesized into proteins

Exception: a few DNA viruses can replicate in cytoplasm because they carry polymerases

DNA –> RNA –> mRNA –> proteins

88
Q

Characteristics of RNA viruses

A

Mostly single stranded
replication occurs in the cytoplasm
can use its RNA to immediately synthesize proteins

RNA –> mRNA –> Proteins

89
Q

What is a positive strand of RNA

A

RNA virus that serve as mRNA and can immediately be translated into proteins

RNA/mRNA –> proteins

90
Q

What is a negative strand of RNA

A

Viral RNA must first be transcribed into mRNA then can be translated into proteins

RNA –> mRNA –> proteins

91
Q

What are retroviruses

A

reverse normal transcription

reverse transcriptase will transcribe the RNA from the virus into DNA and then incorporates it into the host’s cell

DNA <– RNA

92
Q

Viral Replication APURAM

A

study on slides for more detail lol

Attachment
Penetration
Uncoating
Replication
Assembly
Maturation
Release

I&I (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions