Brainscape's Knowledge GenomeTM

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


See full index

Biom1071 > Module 6 > Flashcards

Module 6 Flashcards

1
Q

What is a microbe?

A

It is a bacteria, virus, helminth, parasite or fungi

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

What are the 4 relationships for microbes interacting with hosts?

A
  1. Commesnalism: 1 benefits, no effect on the other
  2. Mutualism: both benefit
  3. Parasitism: 1 benefits, other is adversely affected
  4. Opportunism: a change in the living relationship, which causes parasitism: Staphylococcus aureus, clostridioides dificile and escherichia Coli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define Kochs Postulates

A
  1. Suspected pathogen must be in all unhealthy and none in healthy population
  2. Pathogen must be grown in a pure culture
  3. Pathogen must be able to infect a healthy animal
  4. Pathogen must be reisolated and shown to be the same pathogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the exceptions of Kochs postulates?

A
  1. Can’t be grown in a pure culture
  2. Asymptomatic patients
  3. Not present in animal models
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 6 steps of infection?

A
  1. Attachment and entry, evades innate immune response and causes infection
  2. Local/general spread to the body, containing to evade immune response
  3. Multiplication and strengthening
  4. Evasion of host defenses: full life cycle and microbial battle
  5. Shedding/transmission to spread to new hosts
  6. Damage to host
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the 6 stages of disease?

A
  1. Incubation: sick but no or little symptoms
  2. Prodromal: exponential replication, worsening of sickness
  3. Invasive: extreme exponential replication, extreme sickness, pathogen out competing immune system
  4. Acme: peak
  5. Decline: immune response winning
  6. Convalescence: Recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 2 ways of visualizing bacteria?

A
  1. Macroscopy: naked eye. 16 streak, shame, size, pigmentation, elevation, margin, opacity, texture
  2. Microscopy: using a microscope, staining
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the gram stain technique?

A

The staining of bacteria to distinguish between gram negative and positive

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

What is the difference between gram -ve and +ve

A
  1. +ve has thick cell wall
  2. -ve creates AB resistance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the structure of the gram positive bacteria

A
  1. Thick cell wall: peptidoglycan layer
  2. Within the wall traverses the lipoteicoic acids and are anchored to the membrane
  3. Lipid bilayer plasma membrane with integral proteins
  4. Evolved with humans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the structure of gram negative bacteria

A
  1. Outer membrane with porins and Lipid A
  2. Lipid A has lipid polysaccharides attached with an O-antigen at the end.
  3. Below this membrane is a thin peptidoglycan layer within the periplasmic space
  4. Below this is the cytoplasmic membrane
  5. Evolved with dirt, becomes AB resistant
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why is gram -ve ba trial more resistant to AB than +ve?

A

Because the lipid A, lipopolysaccarides, O-antigen and porins can adapt to AB, making it harder to kill or invade the bacteria.

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

What are the staining techniques to distinguish gram +/-ve bacteria?

A
  1. Crystal Violet: peptidoglycan purple in +ve
  2. Iodine sets the staining
  3. Alcohol: washes away not set stains (-ve)
  4. Safranin: red stain of -ve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 3 energy sources of bacteria?

A
  1. Oxygen (aerobic/anaerobic)
  2. Carbon/nitrogen (sugars/proteins)
  3. Enzymes (cytochrome oxidase)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the 3 tests to determine a bacteria energy source?

A
  1. Fermentation: sugars present, red:none, yellow: lots, anaerobic, yellow with bubble: lots aerobic
  2. Catalase: bubbles of hydrogen peroxide
  3. Oxidase test: purple enzymes are present
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe bacterial fission

A
  1. DNA makes 2 identical copies
  2. Each copy moves to polar ends of the cell
  3. Cell splits to make 2 genetically identical copies
17
Q

Describe the phases of growth

A
  1. Lag phase: initial adaptation to conditions
  2. Logarithmic phase: exponential increase
  3. Stationary: division=deaths
  4. Death: decrease in cell numbers
18
Q

How is bacterial quantity measured?

A
  1. Turbidity
  2. Density

Measured within a spectrometer and optical density taken

19
Q

Describe the characteristics of a virus

A
  1. Not living
  2. Needs a host cell to reproduce
  3. No machinery of its own
  4. No cell membrane
20
Q

What is the lifecycle of a virus?

A
  1. Attachment to host
  2. Penetration of cell
  3. Uncoating to release viral genome
  4. Replication
  5. Assembly
  6. Maturation and release of progeny through membrane of cell
21
Q

What is tropism?

A

Where the virus has a specific target, eg. Humans only, organ only, specific cell

22
Q

Describe the early stages of viral lifecycle

A
  1. Nucleocapsid releases genome
  2. Genome both transcribes to make new capsid proteins and replicates to make new genomes
  3. New proteins and genomes form together to make lots of new nucleocapsids
  4. Now ready for release! Late lifecye
23
Q

Describe the late lifecycle of virus

A
  1. Nucleocapsid either lyses the host cell to release nucleocapsids (naked)
  2. Nucleocapsid pinches cell wall of host cell to create a viron coat for protection (enveloped)

Biom1071 (6 decks)

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