Brainscape's Knowledge GenomeTM

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


See full index

M&I > Block 1 - global influences of microbes > Flashcards

Block 1 - global influences of microbes Flashcards

1
Q

list some applications of microbes

A 
drugs 
vaccines
food
bioterrorism 
genetic engineering 
decontamination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

list some cellular biological entities

A

fungi
protist
bacteria
archaea

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

list some acellular biology entities

A

viruses
viroids
prions

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

what are kochs postulates

A

isolation and confirmation of a particular organism with a specific disease
4 criteria reliant on pure culture of microbes

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

what is a windogradsky column

A

used to stratify microbial communities in a sample

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

what developments have allowed us to isolate and culture many more bacteria

A

development of agar
identification of different media
growth temperatures
oxygenation etc

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

from which kind of bacteria are antibiotics mainly isolated from

A

soil bacteria

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

list some roles of the microbiome

A

availability and uptake of nutrients
resistance to disease
regulation of immune response
generation and uptake of key dietary factors

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

what can be a consequence of losing a microbial population in our gut

A

we may not be able to attain all the required nutrients

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

what is the purpose of the earth microbiome project

A

seeks to understand patterns in microbial ecology across the biomes and habitats of the planet

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

what is the iCHIP

A

allows culturing of microbes that are difficult to grow

- currently being used to culture bacteria capable of making new antibiotics e.g. against c. difficile

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

what are the characteristics of prokaryotes

A

no nucleus
DNA in cytoplasm
only ribosomes
no bacterial wall

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

what are the two categories that allow us to classify microbes by action

A

saprotroph

pathogen

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

what is a saprotroph

A

feeds on dead organic material

useful in digestion and manufacture of food products

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

what is a pathogen

A

feeds on plants and animals - causes diseases e.g. TB, pneumonia

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

what are the 4 ways we classify microbe shape

A

coccus - spherical
bacillus - rod
spirillum - spiral
vibrio - comma

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

what are the 2 ways we can classify microbes by their reproduction

A

sexual - DNA exchange

asexual - by bipartition - upon reaching a certain size the stem cell divides originating 2 offspring

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

what is 16S

A

a bacterial ribosome protein which is highly conserved and functionally very consistent
it is essential for translation of bacterial proteins but undergoes small changes over time
conserved and variable regions are used for bacterial identification

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

16S can be used as a ………… …………. to determine evolutionary relatedness

A

molecular clock

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

how do we identify a bacteria using 16S

A

primers have been created to hybridise to variable 16S regions and PCR analysis is carried out

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

using 16S sequencing we can estimate divergence by looking at similarity of sequences using …………. …………….

A

phylogenetic trees

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

what are the 3 domains of life

A

eukaryotes
archaea
bacteria

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

list some common traits between archaea and eukarya

A

have introns between genes
RNA pol/TFs more similar to eukaryotes than prokaryotes
translation initiator - methionine (bacteria - formylmethionine)

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

what are some unique features to archaea

A

methanogenesis
non pathogenic
thermophilic

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

give evidence of archaea being diverse colonisers

A

they colonise hydrothermal vents, high pressure environments, cold and dark marine environments, high salt concentrated areas, wetlands, sediment, GI tract

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

describe vent thermophiles

A
  • chemoautotrophs
  • survive extreme temperature and pressure
  • black smokers formed by precipitation of inorganic compounds
  • microbes generate energy by reducing sulphur to H2S which is used as an electron acceptor for the energy source
  • water drains –> heated by magma –> steam rises –> water emerges and cools, precipitating FeS and other minerals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

describe the symbiotic relationship of the Hoff crab (kiwa tylari) and bacteria

A
  • survives by eating bacteria it farms on hairs on claws
  • bacteria proliferate as chemoautotrophs and utilize inorganic chemicals released from the vent (carbon source)
  • crab provides shelter and protection from extreme temperature which allows persistence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

why does culturing of some microbes require specialist equipment from NASA

A

because the extreme conditions of their natural environment need to be maintained

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

what is P.abyssi

A

a microbe that forms single cell biofilms on rocks and pass nutrients in order to persist in the community
cell grow as flat discs with cannulae (cytoplasmic extensions) that link the organisms together

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

give an example of archaea that don’t prefer extreme conditions

A

methanogens in the gut

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

why do we know so much about true bacteria

A

it is because of their ability to cause disease
they are good models for understanding fundamental mechanisms
true bacteria offer solutions to many problems

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

what is the order of classification

A 
domain 
phylum 
class 
order
family 
genus 
species 
strain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

why is it common to find antibiotic producing microbes in the soil and sediment

A

find gram positive due to their peptidoglycan coat and endospore formation which generate chemicals to kill competitors e.g. antibiotics form streptomyces

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

what are the 2 types of bacteria

A

archaebacteria and eubacteria

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

describe bacillaes

A

firmicutes recovered from soil samples grown aerobically and survive at high temperature
they are a model for spore production (sporulation triggered by starvation

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

describe actinomycetes

A

they are actinobacteria
aerobic spore forming bacteria that form hyphae (fungi also produce these projections)
they make antibiotics in their secondary metabolism
they include Streptomyces
they produce anti-cancer/fungal/helminth drugs

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

explain how microbes have a dual role in climate change

A

they are sometimes the cause of increased greenhouse gases due to the products of their metabolism but they can also be the solution to many of the climate problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

which organisms can fix CO2 by photosynthesis

A

plants
algae
cyanobacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

describe marine bacteria/algae

A
  • responsible for 50% global CO2 fixation
  • live in the top 200m water column
  • absorb light using pigments and have a gas vesicle for depth adjustment to maximise light capture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

describe phytoplankton

A
  • they are photoautotrophic cyanobacteria that fix CO2 similarly to plants
  • light harvesting apparatus in thylakoid membranes and rubisco in carboxysomes
  • all O2 derived from plants or cyanobacteria containing chloroplasts (water used as an electron donor, releasing CO2)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

cyanobacterial blooms fix CO2 but also have negative effects, what are these

A
  • changes is nutrients, temp and light intensity
  • loss of stratification of water
  • organic material dies due to lack of light and organisms that utilize this material deplete the O2 and the water becomes anoxic which attracts anaerobic organisms and can support most marine life
  • bacteria can produce metabolites/by products that affect water quality and can be toxic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what is a dead zone and how do they result

A

run off –> algal blooms that crash and are consumed by heterotrophic bacteria –> O2 depletion –> kills fish and invertebrates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

describe the carbon cycling chained events

A

phytoplankton fix CO2 –> phytoplankton consumed (carbon oxidised by respiration –> CO2 and water) –> small crustacea consumed and more complex molecules assimilated
heteroorganotrophs cannot generate their own food but breakdown what they consume for energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

what are carbon sinks and how do they form

A

CO2 return occurs by respiration but the bottom of the ocean is low in O2 so not many microbes can return CO2 from the dead material
C compounds like methane and alcohols compress at the bottom of the ocean –> fossil fuels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what is the problem with burning fossil fuels

A

lots of CO2 release which was fixed millions of years ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what are methanogens

A

obligate anaerobe chemoautotrophic archaea that use H2 as a terminal electron acceptor during anaerobic respiration

  • fix CO2 through reduction of chemicals like H2S to methane
  • they also produce methane from short chain FA produce by other gut bacteria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

gut microbe energy harvest depends on ………..

A

symbiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what do gut microbe primary degraders do

A

attack bonds –> initial breakdown

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

what do gut microbe secondary fermenters do

A

they result in further breakdown - produce by products including CO2 and H2 which can be useful e.g. butyrate for gut health

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what is one of the endpoints of gut microbial activity

A

methane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

what are gut metabolism short chain FA by products used for

A

as a C source for by enterocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

methanogens thrive on carbohydrates broken into ….. ….. ….

A

short chain FA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

describe termite gut symbiosis

A
  • termites produce CO2 and CH4 during wood digestion
  • wood digesting bacteria in gut, mixotricha paradoxa (eukaryotic protist) contain bacterial endosymbionts which digest lignin in wood to generate acetate which is further broken down
  • polysaccharides –> acetic acid + organic acids are utilized by termites. H2 and CO2 generated in conversion are used by methanogens to make methane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

why is permafrost thawing

A

due to CO2/methane release due to increasing accessibility of microbes to organic material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

how are changes in population resulting in increased methane in the environment

A

intensified farming for food –> more animals and organic material –> higher levels of methane in the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

how can we reduce cattle emissions

A

by changing the cellulose (hay) diet to a grain diet which has more starch and so is more digestible and results in faster growth
this diet has also shown decreased FA and methane through 16S sequencing
however there appears to be an increased risk on pathogenic e. coli colonising due to the microbiome change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

which greenhouse gas is 100x more harmful than CO2 and how is it produced

A

N2O - produced due to microbial activity in nitrogen cycling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

what happens to N fixation in some bacteria when other N sources are available

A

it is turned off

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what is the haber process

A

N2 + H2 under extreme temp/pressure = NO3 for fertilizers etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

what are the steps in Nitrogen fixation

A
  1. N2 –> NH3 : N2 fixed by clostridial sp in soil and cyanobacteria in marine environments (anaerobic organisms as nitrogenase enzyme is O2 sensitive). Energy dependent - needs 16 ATP
  2. Nitrification NO3 (ate) –> NO2 (ite). Nitrates are accessible by plants. non utilised nitrates or nitrites are used by microbes for energy under anaerobic conditions
  3. denitrification : Reduce back to atmospheric N2.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

what is the rate determining step for plant growth and which greenhouse gas does this influence the production of

A

NO3 soil availability is the rate determining step for plant growth and influences N2O production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

what does runoff of fertilizer result in

A

denitrification in marine environments

lots of excess nitrate which undergoes denitrification in the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

give examples of bioremediation

A

detoxification of pollutants and environmental contaminants

combinations of landfill microbes breakdown and use complex carbohydrates as a carbon source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

how are biofuels made and why are they good

A

many methods
fungi ferment sugars and produce ethanol as a by-product
biofuels are good because they are carbon neutral - CO2 release of CO2 that was fixed by plants used to make it (not from pre-existing sources)
renewable source of energy
can be used in isolation or mixed with other fuels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

what are disadvantages of biofuels

A

biofuels are currently made of food - not so good - should use non food crops
use of land that could be used for food
requires energy
damaging in non compatible fuel systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

what are the options for feedstocks for biofuels

A

easiest - sugar crops - ferment, distil
harder - starch crops - hydrolysis, ferment, distil
hardest - lignocellulose material - pre treatment, hydrolysis, ferment, distil
as it gets harder it is because they require greater processing and energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

……..……. …………. to express enzymes involved in simultaneous saccharification (………….) and fermentation of lignocellulosic material –> implications for cellulose and ethanol industry e.g. ……… ………….. ……….. …….. …………

A

genetic engineering
hydrolysis
efficiency and waste material usage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

give some reasons for the importance of plants

A

the provide O2, food, maintain biosphere and carbon storage, use for biofuel, use for vaccines/antimicrobials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

describe the plant immune system

A

no specialised circulating immune cells
every cell can amount an immune response
non circulatory vascular system transports immune cells from infection site to uninfected tissues
PAMPs and PRRs are sued
they have memory and acquired immunity
memory is transmitted to subsequent generations i.e. in an epigenetic manner

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

describe the process of plant pathogen detection and coevolution

A

pathogen type recognised –> PAMP triggered immunity –> cellular signalling –> immune response –> pathogen evolution –> effector triggered susceptibility –> immune response impaired –> plant evolves counter measures –> effector triggered immunity –> immune response
this is an example of coevolution of plants and the pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

coevolution is more controllable in plants than animals - true or false

A

false - coevolution in plants is not as controlled as in animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

what are phytohormones and give 3 examples

A 
they are plant hormones with central roles in signalling to each other and other plants in response to disease 
3 examples
- Jasmonic acid 
- ethylene 
- salicylic acid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

do plants encode pathogenesis related proteins

A

yes they act as defence proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

give an example of how Jasmonic acid can defend the plant

A

it defends against caterpillars

caterpillar saliva + leaves –> JA –> wasps (parasitoid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

what is aspirin in relation to phytohormones

A

it is acetylated salicylic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

what are some plant defences against insect attack

A

hard waxy surfaces
toxins
recruitment of parasitoid insects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

what are some plant defences against grazing

A

thorns
silical granules in leaves - grasses
toxins such as alkaloids in foliage, fruits, seeds
proteins such as ricin, lectins and proteinase inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

what are parasitoid insects

A

they are insects that are attracted by emergency compound e.g. JA in response to damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

why must certain microbes be tolerated by plants and give some examples

A

e.g. Mycorrhiza - roles in plant nutrient exchange, communication, growth, productivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

what are the 2 types of mycorrhiza

A

ecto-mycorrhizae (outside roots)

endo-mycorrhizae (inside roots)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

what is the rhizobium

A

a genus of gram negative soil bacteria that fix nitrogen and colonize plant cells within root nodules
they convert N –> NH3 –> organic nitrogenous compounds
the plant provides organic compounds from photosynthesis to bacteria
MUTUALISM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

the rhizobium is in …… with plants

A

synergy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

give examples of each of the 5 plant pathogen types

A

virus - TMV
bacteria - agrobacterium tumefaciens
oomycete - potato blight
fungus - dutch elm disease and ash dieback disease
nematode - potato cyst nematode and pine wilt nematode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

describe TMV in plants

A
  • it is a +ve ss RNA virus with helical symmetry. it infects the tobacco plant and other members of the solanacaea. it causes mosaic mottling of leaves
  • spread: infects wounds –> replicates –> spreads via plasmodesmata - seed borne spreading by contaminated hands/tools
  • structure: rod form of delicate spiral with RNA in centre and the protein coat surrounding the RNA self assembles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

what was the first identified filterable virus

A

TMV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

which plant virus is useful for making vaccines

A

TMV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

describe agrobacterium infection of plants

A

tumour galls caused by TDNA in the T plasmid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

how can agrobacterium be used in research

A

replace TDNA with gene of interest to create transgenic plants

  1. cut TDNA with restriction enzyme and insert DNA of interest to make a recombinant plasmid
  2. introduce plasmid to plant cells and culture
  3. grow plant expressing new trait
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

what pathogen causes potato blight

A

phytophthora infestans - oomycete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

describe potato blight infection

A

phytophthora infestans grows in plant tissues initially as a biotroph (depending on living cells) then hyphae emerge from stomata once the plant is dead - the spores that emerge are windborne and spread

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

what is unexpected about the potato blight pathogen

A

unusually large genome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

describe the irish potato famine

A

successive phytophthora infestans epidemics –> mass starvation
monocultures are very susceptible to infection - diversity in plants is important

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

describe dutch elm disease

A

it is caused by fungi ophiostoma ulmi and ophiostoma novo-ulmi
they block water conduction channels (xylem) causing wilt and host response also plugs vessels
shoots die back from the tip
cell wall degrading enzymes help the fungus invade the xylem and hyphae grow between xylem cells and the whole plant dies
spread - elm bark beetles burrow in trees and lay eggs, larvae then burrow sideways and pupate, transmitting as adults

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

describe ash dies back disease

A

caused by chalara fraxinea and its sexual stage - hymenoscyphis pseudoalbidus
it is tree borne beetlw transmitted and the spores are windborne

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

what are nematodes

A

they eukaryotic organisms and most of them are sexually reproducing
moult 4 times during development
developmental arrest when the environment is poor
plant parasitic nematodes cause lesion/gall formation
most cause non specific symptoms
most are parasite of roots
they have protrusible stylets or mouth spears connected to secretory apparatus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

nematodes have internal ………… …………. to antagonize muscle

A

turgor pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

what is the difference between endo and ecto nematodes

A

endo migrate into the tissues and ecto use the roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

give an example of how nematodes can re-differentiate host tissue

A

giant cells - stylet penetrates cell wall and gland secretors are deposited which interact with cells making them giant for feeding
other examples include:
stationary cells
non muscular cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

what are potato cyst nematodes caused by

A

heterodera and globodera spp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

why are cyst nematodes especially bad for farmers fields

A

because they can survive for up to 20y and contaminate fields for up to 30y

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

how do cycst nematodes infect plants

A

they invade the root tip until they reach the inner cortex –> moult to J2 in egg –> J2 inserts stylet –> induce cell to become syncytial cell –> nematode moults to adult –> males revert to vermiform and leave roots in search of females –> females grow and break through the root surface –> female death –> cyst forms containing eggs and lasts for 20+ years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

what factors do nematodes have that help them infect plants

A

cell wall modifying enzymes
suppression of host defences
auxin pathway interruption (high concentration at feed site)
effectors that target plant cell nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

describe infection by the pine wilt nematode

A

caused by burcaphelenchus xylophilus which invades the tree, kills it, feeds on fungi then consume it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

describe the large scale HGT seen in pine wilt disease

A

transfer of information from fungi to nematode (get cellulases - cell wall modifying genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

in terms of cattle what are the costs in terms of health and economic risks

A 
health risk -
animal health and transmission
poorly developed animals --> starvation 
foodborne disease 
endemic disease 
economic risk - 
diagnostics need to be efficient 
vaccines/medicines need to be effective 
market disruptions/productivity loss/costly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

what causes TB in cattle

A

Mycobacterium bovis but it can jump species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

how is there a one health aspect of zoonotic infections

A

because animal health influences human health and human health influences animal health

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

name 3 diseases of cattle: one of each category
bacteria
parasite
virus

A

bacteria - bovine TB
parasite - Nagana
virus - rinderpest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

what agents cause TB in cattle, humans and birds

A

cattle - M bovis
humans - M TB
birds - M avium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

as well as being an agent for bird TB what is another roe of TB avium

A

opportunistic pathogen in AIDS patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

what are the phylum, genus and species of the TB pathogen in cattle

A

phylum - actinobacteria
genus - mycobacterium
species - bovis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

is mycobacterium bovis in extracellular or intracellular bacteria
also describe its structure

A

intracellular

curved rod shape gram +ve with a high lipid content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

what is meant by M TB being acid fast

A

have mycolic acid in cell wall so retain carbol fuschin colour because decolouriser doesn’t enter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

what are the symptoms of TB in cattle

A

weakness, coughing, weight loss
head lymph nodes affected first then tubercles form on surface of chest cavity and lungs
long replication rate –> can take years to develop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

when does testing for TB in cattle occur

A

evey 1-4y and before movement

116
Q

how do farmers deal with cattle infected with M TB

A

immediate slaughter

117
Q

how does M TB evade the immune system

A

macrophages usually take up bacteria and contain them in a vacuole (phagosome). this fuses with the lysosome forming a phagolysosome resulting in low pH and ROS. HOWEVER M TB PERSISTS
they block phagosome maturation and prevent phagolysosome fusion by secreting protein and lipid factors. they have enzymes that make them resistant to low pH and ROS. immune cells engulf M TB but can’t kill it –> tubercles
long term evasion –> granuloma

118
Q

what is needed to kill mycobacteria

A

activated macrophages (e.g. by IFNg) will kill them effectively

119
Q

what is a granuloma

A

build up of immune cells

120
Q

how do we ensure that farmers are treated fairly for losing cattle to TB

A

they are compensated with the amount depending on the quality of the cow

121
Q

how does the UK ensure that humans are no infected with TB by cattle

A

all milk is now pasteurised and screened

122
Q

how is TB spread

A

it is spread by aerosol and from wildlife reservoirs e.g. badgers

123
Q

how are vaccines implemented in TB prevention

A
  • humans are vaccinated with an attenuated BCG strain
  • there has been investment in badger and cattle
    vaccines
  • badger vaccines reduce the risk of TB in the badger vaccinated and its cubs too
124
Q

what are the problems with TB vaccines

A
  • no effect in already infected badgers
  • costly and time consuming to vaccinate wildlife
  • an oral vaccine is difficult to develop
  • the cattle vaccine has shown mixed results and we can’t tell the difference between vaccinated and infected cattle
125
Q

what kind approach will be required to eradicate TB and what will be required for this

A

a combinatorial approach - would involve vaccination, culling, monitoring, proper animal husbandry

126
Q

what is another name for nagana

A

African animal trypanosomiasis

127
Q

how is nagana spread

A

it is caused by trypanosomes and spread through tsetse flies

128
Q

what are the symptoms of nagana

A

swelling, fever, reduced milk, fertility issues, weight loss, malnutrition

129
Q

where is the tsetse belt

A

central africa

130
Q

which 3 trypanosomes cause nagana

A

congolense - common, resides in blood vessels –> anaemia
virax - can spread independent of tsetse flies and are also found outside the tsetse belt
brucei - only causes disease in animals, gambiense and rhodesiense cause African sleeping sickness in human s

131
Q

how do trypanosomes evade the immune system

A

antigenic variation - variant surface glycoprotein switching
altering the immune response is costly and is what leads to symptoms of nagana

132
Q

how do we treat and prevent nagana

A

vector control
drugs exist e.g. berenil
only breed trypanotolerant cattle
no vaccine exists yet

133
Q

what is rinderpest

A

highly contagious viral disease of water buffalo, cattle and other wildlife
It is caused by paramyxoviridae a morbillivirus

134
Q

what is the structure of paramyxoviridae

A

ss -ve sense RNA
multiplies in host cell
similar to measles virus

135
Q

the mass starvation and lack of grazing animals once caused by rinderpest lead to thickets - what is the result of this

A

tsetse flies increase

136
Q

how is rinderpest spread

A

close contact (breath, secretions, excretions)

137
Q

what are the symptoms of rinderpest

A

fever, diarrhoea, oral lesions

138
Q

rinderpest had a high/low mortality and high/low morbidity

A

high

high

139
Q

how does the paramyxoviridae suppress the immune system

A
  • infected individuals have long lasting morbillivirus immunity but suffer from transient generalised suppression of immune responses to other pathogens
  • reduced B cells, monocytes, neutrophils, some T cell types
140
Q

how was rinderpest eradicated

A

attempts: slaughter, movement restrictions, vaccinations

eradication campaign: cattle vaccination, diagnostic test, tissue culture rinderpest vaccine

141
Q

what is ringworm

A

trichophyton verrucosum fungal infection off hair and keratinised layers of the skin also known as dermatophytosis which has economic consequences to farmers
zoonotic - direct contact and bites - largely occupational

142
Q

ringworm has high/low morbidity and high/low mortality

A

high morbidity

low mortality

143
Q

how do we prevent and treat ringworm

A

vaccination reduces the level of outbreaks
treatment shortens the period of clinical signs although the infection is generally only self limiting
the environment must be disinfected because the chlamydospores persist in the environment

144
Q

what is FMD

A

highly contagious virus of hoofed animals which is difficult to control with large economic threats to agriculture
incubation period of up to 2 weeks and transmission period can occur before culling
caused by picornavirus

145
Q

what is the structure of the picornavirus that causes FMD

A

non enveloped ss +ve sense RNA with 7 serotypes

146
Q

how does having multiple serotypes in FMD complicate treatment

A

there are 7 serotypes and it is difficult to make a treatment for them all
only get immunity to the serotype infected with
it also complicates diagnosis

147
Q

FMD has high/low morbidity and high/low mortality

A

high

high

148
Q

what are the symptoms of FMD

A

fever, blister on feet and mouth, temporary immunosuppression, reduced milk production and lameness (has quite a bad effect on productivity)

149
Q

how is FMD transmitted

A

direct contact or fomites and can survive in the environment for months
recovery is rare and it remains latent and can resurface

150
Q

what is the preferred way to deal with animals with FMD

A

culling

151
Q

what controls have been put in place in previous FMD outbreaks

A

culling
surveillance zones
ban on movement

152
Q

how do we diagnose FMD

A

it is only detectable 2 days before clinical symptoms
ELISA is the quickest method - detection of antibody/antigen in serum and can be serotype specific
qPCR takes longer
genome sequencing takes even longer and requires expertise
virus isolation takes even longer and you need a cell line

153
Q

what controls are used for FMD when a cow is infected

A

ring culling
disinfection of premises
restriction of movement

154
Q

how is vaccination used for FMD

A
  • the vaccine only gives short term immunity and the virus has high mutation rate
  • it is generally given to limit infection in an outbreak but culling more common
  • infected and vaccinated cattle can develop a carrier status (latent in lymph nodes)
  • the vaccine is live and chemically attenuated so production is risky
  • it is challenging to produce a vaccine against all strains
  • subunit vaccines are in development which are safer but not as effective
155
Q

how are domestic cats a threat to wildcats

A

infections of domestic cats can infect wildcats which are endangered

156
Q

name 2 feline retroviruses

A

feline leukaemia virus

feline immunodeficiency virus

157
Q

how can cats be a threat to pregnant women

A

they can get toxoplasmosis which is transmissible to pregnant females

158
Q

what are retroviruses

A

enveloped + ss RNA viruses that use RT for replication. DNA integrates into the host genome. they are classed as proviruses - they remain latent and resurface

159
Q

what are the steps in the retrovirus cycle

A
  1. RT converts RNA –> DNA once RNA enters host
  2. DNA integrated to host chromosomes
  3. viral particle assembly and exit
160
Q

what is FIV

A
  • Feline immunodeficiency virus
  • the cat equivalent of HIV
  • vaccine available - fel-o-vax - chemically inactivated but underused do to lack of differentiation
  • infects Th cells and impairs the immune system
  • spread by scratches and bites
161
Q

what is FLV

A
  • feline leukaemia virus
  • transmitted from saliva in bites
  • causes anaemia and lymphoma in cats
  • some cats remain viraemic but will die in 2-3 years
  • originally thought to be cancer but it is transmissible (horizontal transfer)
  • may be possible to make a vaccine against lymphosarcoma and other FLV associated diseases
  • there are vaccines currently but they need to be given soon after birth and they don’t differentiate
  • supportive therapies - keep indoors, treat secondary infections, maintain vaccinations
  • diagnostics - ELISA but false +ves common - PCR and virus culture culture are more time consuming
162
Q

describe H5N1

A 
bird flu 
bird to human transmission 
no human to human transmission 
60% mortality 
easier to track n
163
Q

describe H7N9

A 
less deadly - 30% mortality 
difficult to track
bird to human transmission 
human to human transmission 
Tamiflu resistance (drug)
164
Q

what is the family and genus of avian influenza

A

family - orthomyxoviridae

genus - alphianfluenzevirus

165
Q

how do we get different influenza subtypes

A

based on N and H antigenic variation

166
Q

what is H (hemagglutinin)

A

causes aggregation of rbcs, glutination of heme - recognises host - 18 types

167
Q

what is N (neuraminidase)

A

controls release of new viral flu particles - 11 types

168
Q

what is trichomonas

A

trichomonas gallinae is a protozoan parasite and causes yellow deposits/lesions on the oral cavity and can restrict diet leading to death by malnourishment
the lesions break down the mandible bone in the mouth

169
Q

how are trichomonas spread

A

they don’t survive long outside
they spread through unwashed birdfeeders
it can also infect domestic birds but there is no zoonosis

170
Q

how do we prevent trichomonas

A

clean your bird feeders

171
Q

what is eimeria

A

causes coccidosis in poultry and goats
caused by many different species (one affects one type of animal)
caused by an intracellular protist and is an apicomplex parasite
eimeria tenella is a major pathogen of intensively farmed chickens in close proximity

172
Q

how is emieria transmitted

A

fecal oral - introduced on farmers boots or new infected stock

173
Q

what causes the pathology of emeria

A

apical complex used to enter host - replicates in the intestinal epithelial cells and causes tissue change and sometimes bloody diarrhoea

174
Q

what is the life cycle of emeria

A
  1. oocyst excreted - contains 4 sporocysts which each contain 2 sporozoites
  2. sporulation - sporozoites released - humidity/temp dependent
  3. sporozoites invade gut epithelium (symptoms appear) and undergo asexual replication
  4. sporozoites –> merozoites and invade new cells (if they don’t they develop into male/female gametes)
  5. sexual replication produces new oocysts which are excreted
    (see diagram)
175
Q

how do we control eimeria

A

chemo (anti coccidial drugs) but emerging AMR
live attenuated vaccine available but not very effective
improve the environment - less crowded - free range effective

176
Q

what is the only human retrovirus that causes cancer

A

HTLV1 - causes ATL

177
Q

how does HIV indirectly lead to cancer

A

via immunosuppression

178
Q

what are the 3 mechanisms for retroviral transformation

A

transducing (animals only)
cis-activating (animals only)
trans-activating (humans e.g. HTLV1)

179
Q

what does a normal retrovirus genome contain

A

promoter - controls viral gene transcription
gag - codes proteins that make up the capsid - structure
pol - important for coding RNA –> DNA, also makes other enzymes
env - encodes glycoproteins on surface of virus particles - help bind/enter cells

180
Q

describe transducing reteroviruses

A
  • usually replication deficient without helper virus
  • has v-onc - oncogenes that encode proteins for cell growth - cause MAPK that leads to cell proliferation they are acquired form infected cells and altered to be hyperactive. some normal genes are lost when the v-onc gained
181
Q

give an example of a transducing retrovirus

A

rous sarcoma virus - got all the replication machinery + viral oncogene (tyrosine kinase-v-sarc) - causes sarcomas in chickens

182
Q

give examples of some retroviral oncogenes

A 
sis
src
abl
ras
jun 
myc
183
Q

describe cis activating retroviruses and give an example

A

no viral oncogenes but everything they need to replicate
integrate into the host chromosomes close to normal cellular oncogene and disrupt its function (upregulate -> proliferation)
e.g. avian leukosis, mouse mammary tumour, murine leukaemia virus

184
Q

describe trans activating retroviruses and give an example

A

viral protein regulates transcription of the virus and cellular genes
tax - binds onto LTR and controls viral and cellular gene transcription (transcriptional regulator e.g. if it binds to T cell, causes upregulation of IL-2 genes causing T cell to proliferate continuously –> cancer
e.g. HTLV1

185
Q

describe the tumour formation efficiency of the transducing, cis activating and trans activating retroviruses

A

transducing - high
cis activating - high/intermediate
trans activating - very low

186
Q

describe the tumour latency of the transducing, cis activating and trans activating retroviruses

A

transducing - short (days)
cis activating - weeks/months
trans activating - months/years

187
Q

describe the replication of the transducing, cis activating and trans activating retroviruses

A

transducing - defective
cis activating - competent
trans activating - competent

188
Q

describe the oncogenic element of the transducing, cis activating and trans activating retroviruses

A

transducing - cell derived oncogene
cis activating - cellular oncogene activated
trans activating - regulatory protein controlling transcription

189
Q

are there any transducing retroviruses in humans

A

no

190
Q

viruses associated with malignancy …………. in the host after primary infection

A

persist

191
Q

what is the time interval for retroviral malignancy development usually like

A

long

192
Q

describe HPV

A
  • family - papovaviridae, tumour - cervical cancer
  • there are 14 high risk types
  • 16 and 18 cause most cervical cancers and precancerous lesions
  • also associated with anus/vulva/vagina/penis cancers
  • HVP E6 and E7 genes are expressed in tumour cells and interact with p53 and pRb (tumour suppressor proteins)
193
Q

what parts of the world is HPV cancer most common

A

less developed regions that lack screening

194
Q

describe the structure of the cervix in relation to HPV

A
  • ectocervix - stratified epithelium. basal layer - cells capable of dividing. towards the top layer cells differentiate and are less capable of dividing
  • endocervical canal - single layer of cells - glandular cells transform into squamous cells - most prone to HPV infection - these cells are sampled in screening
  • endocervix - soft columnar glandular cells
195
Q

how does HPV infection occur

A
  • abrasion on the cervix - straight to basal cells

- infects columnar cells in the canal to get to basal cells

196
Q

describe the HPV genome

A 
8 genes
E genes (early expression) 
L genes (late expression)
197
Q

what part of the HPV genome does the immune system target

A

targets L1 proteins but they are not recognised due to the immune system being more active at the basal level (layer where L1 isn’t expressed)

198
Q

what are the basic steps from HPV infection to cancer

A

infection (progression) precancerous lesion (invasion) cancer

199
Q

what happens to most people when they are infected with HPV

A

they will clear the virus within 2 years but if not they are at risk of progression

200
Q

how do the epithelial cells change after HPV infection to become cancerous

A

epithelial cells –> basal cells (continual replication) –> fully malignant

201
Q

what is the role of HPV E7

A

when pRB is bound to the E2F (TF) the cell cycle is held in the G1 phase. when not bound to E2F, it drives the cell through the cell cycle
E7 binds to pRB leading to degradation so E2F drives the cell cycle –> cancer

202
Q

what is the role of p53 (along with E6 and 7) in HPV infection

A

when activated by stress p53 induces transcription of genes that mediate either growth arrest (p21WAFI/CIPI) or apoptosis (Bax). p53 level is regulated through interaction with mdm-2 protein which signals p53 degradation. expression of E7 increases p53 levels causing cell cycle arrest. E6 binds to p53 and causes degradation so cell cycle resumes –> cancer

203
Q

what is involved in HPV screening

A

if HPV infected cells are detected in a smear test we check for abnormal cells (cytology) and if abnormal cell are detected we refer for a colposcopy. if abnormal cells are not identified then you are just screened more frequently

204
Q

what is available for HPV in terms of vaccination

A

the current vaccine protects against HPV 6, 11, 16, 18and a new version is looking to protect against 9 types
it used to only be given to teenage girls but not it will also be give to teenage boys as they can be carriers

205
Q

what is Epstein barr virus

A
  • family - herpesviridae
  • tumour - BL, HL, NPC, B/T/NK cell lymphomas, PTLD
  • most primary infections occur in childhood and remain latent in B cells and cancer development is uncommon
  • infection in adolescence or adulthood is associated with glandular fever
  • EBV immortalises in B cells in vitro creating a lymphoblastic cell line - 9 proteins cause immortalisation
206
Q

what are the 3 latency patterns of EBV

A

I. EBNA1 - BL
II. EBNA1, LMP1, 2a, 2b - HL, NPC
III. EBNA1, 2, 3a/b/c, LMP1, 2a, 2b - IM, PTLD, AIDs lymphoma

207
Q

what is the significance of EBNA 3a/b/c in the third EBV latency pattern

A

they are CTL targets - they are not recognised if immunosuppressed and will lead to cancer

208
Q

where is Burkitt lymphoma endemic

A

malarial areas

209
Q

what causes Burkitt lymphoma

A

it is sporadic and caused by EBV infection
it involves ch8 of c-myc TF gene and ch14 where immunoglobin heavy chain Ch locus is. a translocation occurs: c-myc –> ch14 causing proliferation as c-myc is upregulated
(can also get 8-2, 8-22 translocation)

210
Q

what is the Ch locus (involved in BL)

A

it is highly expressed in B cells in BL to make their surface immunoglobins

211
Q

describe the role of EBV and malaria in progression to BL

A

malaria diminishes T cell control of EBV infected cells - those with malaria are slightly immunosuppressed. malarial Ag induce polyclonal B cell proliferation causing induced EBV replication and increased EBV infected B cell pool and thus an increased chance of c-myc translocation. cells that express high levels of c-myc undergo apoptosis but EBNA1 of EBV prevents this –> cancer

212
Q

describe HBV

A
  • family - hepadnaviridae
  • tumour - HCC
  • attacks the liver and can cause acute and chronic disease
  • the older one is infected the less likely they are to develop chronic infection
  • 20-30% adults infected develop cirrhosis and/or liver cancer
213
Q

describe HCV

A
  • family - flaviviridae
  • tumour - HCC
  • can cause acute and chronic hepatitis - those who don’t clear it develop chronic HCV infection
214
Q

what is HCC

A

hepatocellular carcinoma - liver cancer

215
Q

what is the leading cause of HCC

A

HBV and HCV infections

216
Q

what is the indirect mechanism of HCV/HBV infection causing cancer

A

the viruses continually replicate in hepatocytes and need to be killed
the continual regeneration and proliferation increases the chance of a mutation and development of cancer

217
Q

what is the direct mechanism of HCV/HBV infection causing cancer

A

HBV: HBV integrates into host chromosomes and alters oncogene expression. HBx regulates genes involved in signal transduction/cell cycle control
HVC: HCV core protein induces mitochondrial damage/oxidative stress, a trigger of HCC. HCV N55B protein interacts with pRB leading to degradation

218
Q

what are the treatments and prevention mechanisms for HBV and HCV

A

HBV prevention/treatment - increase vaccination, antiviral drugs available for long term therapy but only reduce HCC risk, rather than eliminating it
HCV treatment - new antivirals can cure chronic infection but are expensive and have the best effect when treated before cirrhosis development

219
Q

what is industrial microbiology

A

use of microbes to produce commercial products or carry our important chemical transformations (usually large scale)
can include enhancement of metabolic reactions
often use yeast/mold/bacteria

220
Q

what is the difference between industrial microbiology and biotechnology

A

biotechnology involves genetic modification but industrial microbiology does not

221
Q

are pharmaceutical products like antibiotics and steroids primary or secondary metabolites

A

secondary metabolites

222
Q

name 2 speciality chemicals and food additives

A

vitamins and amino acids

223
Q

describe commodity chemicals and give an example

A

inexpensive chemicals produced in bulk e.g. ethanol

generally primary metabolites

224
Q

what is the basic chemical equation of vinegar production

A

ethanol –> acetaldehyde –> acetic acid

oxidation reactions

225
Q

what is a rate limiting factor of vinegar production

A

high oxygen demand

226
Q

name and describe 2 acetic acid bacteria

A

acetobacter, gluconobacter

they are pH tolerant, aerobic and don’t fully oxidise acetic acid to CO2

227
Q

what are the 3 methods of producing vinegar

A

open vat/orleans -traditional, surface culture, needs mixed
trickle - continuous culture (new ethanol constantly fed in), media constantly turned over
bubble - stirred tank reactor, constant mixing, O2 pumped in from bottom, efficient (no wood taste :((…)

228
Q

describe the trickle method of vinegar production

A

alcohol trickled through woodshavings aerated from below and bacteria coated on shavings (biofilm) - continuous culture –> efficiency

229
Q

describe the bubble method of vinegar production

A

large scale, sparging (inject O2), attached to computer to monitor pH, temperature, O2 demand etc to make efficient

230
Q

describe batch culture and its advantages and disadvantages

A
  • closed system
  • growth declines to diminishing nutrients or accumulation of toxic waste products
  • they are more common because the product may only be required in small amounts intermittently, high product concentration may be required, certain product sonly made in the stationary page, strain instability may require culture renewal, technically easier
  • vessel productivity is not increased
231
Q

describe continuous culture and its advantages and disadvantages

A

open system, fittest bacteria survive, nutrients added and culture removed continuously, organisms grow under steady conditions
advantages - productivity for given sized vessel increased, growth rate can be maintained at optimum
disadvantages - limited uses, technically difficult

232
Q

what is a primary metabolite

A

a metabolite that forms during exponential growth e.g. alcohol

233
Q

what is a secondary metabolite

A

a metabolite that forms in the stationary phase - more complex, not essential for growth, dependent on conditions, closely related bacteria produce closely related metabolites, highly overproduced, often by spore

234
Q

can we get interaction between primary and secondary metabolite pathways

A

yes e.g. antibiotics

235
Q

what are some difficulties with scaling up a reaction

A 
choosing an appropriate vessel 
O2 availability 
mixing 
scaling up volume 
media (e.g. clostridium only grows on solid media)
236
Q

what are the stages of scaling up

A 
lab flask (get commercial interest) 
lab fermenter (alter growth conditions) 
pilot stage plant (introduce instruments and computer control)
commercial fermenter (1000-5000000L)
237
Q

describe the different types of downstream processing of products

A

separation - filtration, centrifugation, disruption of cells (if product intracellular)
concentration - extraction, ultrafiltration, precipitation
purification - chromatography, crystallisation
drying

238
Q

list some properties of a useful microbe

A 
large scale growth 
spore or reproductive cell form 
grow and produce product rapidly 
cheap 
non-pathogenic 
genetically able to manipulate
239
Q

what is brewing

A

the manufacture of alcohol from malted grains

240
Q

how is most alcohol produced

A

by yeast production of ethanol

241
Q

what is gasohol and what are its advantages and disadvantages

A

alternative energy made by yeast

it reduces reliance on fossil fuels and increases fuel efficiency but there are food ethics

242
Q

what yeast is commonly used to make alcohol

A

saccharomyces cerevisiae

243
Q

what types of yeasts are required to make ales and lagers

A

ales - top fermenting

lagers - bottom fermenting

244
Q

how do we make distilled alcohol beverages

A

heat previously fermented liquid to a temperature that volatizes most of the alcohol

245
Q

what is the process of malting

A

Barley (raw material - high C, low N) –> Malt (germination - enzymes convert starch to maltose)

246
Q

yeast use the enzymes from dried …………

A

malt

247
Q

what is the process of mashing

A

malt (crush)–> grist (water)–> wort

248
Q

what are adjuncts

A

they added to malt to increase the carbohydrate content of wort for fermentation e.g. wheat, maize, rice

249
Q

what happens to the wort produced

A

hops are added to it and it is filter and boiled to produce clarified hopped wort

250
Q

what can spare wort be used for

A

cattle feed

251
Q

what can spare clarified hopped wort be used for

A

fertilizer

252
Q

what are the function of hops

A

they have antiseptic properties and prevent spoiling

253
Q

describe the fermentation of ale

A

batch, open vat, top fermenting, s.cerevisiae, pitched with large inoculum, rapid growth –> may need aerated, yeast skimmed off to use again, 5-6 days, 14-23 C, pH 5.2-4.1

254
Q

describe the fermentation of lager

A

batch, bottom fermenting yeast, s.carisbergensis, 8-14 days, 6-12 C

255
Q

describe the maturation process in brewing

A

fresh beer is filtered and centrifuged and stored in storage tanks for a few days for natural conditioning at 4-8 C

256
Q

what is any surplus yeast from beer brewing used for

A

food products

257
Q

what is the difference between beer, lager and ale

A

beer is an umbrella term covering ale and lager

ale and lager differ in taste and are brewed differently

258
Q

in maturation what is the difference in the storage of lager and ale

A

lager is stored for weeks at -1 C

ale is stored for a few days at 4-8 C

259
Q

what is involved in the finishing process

A

pasteurisation and bottling

260
Q

what is the chemical equation for going from maltose to ethanol

A

maltose –> glucose –> pyruvate –> acetaldehyde –> CO2 –> ethanol

261
Q

which chemical process makes the alcohol taste good

A

sugars, proteins, fats –> ethanol + higher alcohols, organic acids –> ester (maturation)

262
Q

what is spoilage caused by in brewing

A

contaminants after boiling wort, from air, water, or pitching yeast

263
Q

why can only certain bacteria/yeast cause food spoilage

A

because of the harsh conditions of the beer (pH, low temp, hops, anaerobic etc)

264
Q

how do we prevent beer spoilage

A

aseptic technique and hygiene
using pure strains
pasteurisation

265
Q

what is the story of the ale conner

A

if trousers stick to the bench the beer is not fermented enough and there is too much sugar

266
Q

what type of organism are the majority of biowarfare agents

A

bacteria and some are viruses

267
Q

what is anthrax

A

a disease caused by bacillus anthracis

268
Q

what about BA makes in good for BW

A

its spores

269
Q

what are characteristics of a good BW agent

A

infectivity, casualty effectiveness, resistance, availability and means of transmission

270
Q

what is LD50

A

lethal does 50 - the lethal dose to kill 50% of the population
the lower the LD50 the more virulent the organism

271
Q

what is more virulent - streptococcus or salmonella

A

streptococcus

272
Q

what is the BA life cycle

A
  • spores taken in (ingested/inhaled)
  • spread to bloodstream and germinate into non spore forming form, generating large numbers
  • spread to different species by biting fly/meat/inhalation
273
Q

what is cutaneous anthrax

A

occurs when the BA has entered a wound
it causes blackened lesions on skin (tissue necrosis)
it is self limiting and is treatable

274
Q

what is inhalation anthrax

A

caused by inhalation of BA spores in the lungs which travel to the blood stream by passing through alveoli
it produces 2-3 toxins and causes haemorrhagic meningitis
it has high mortality and is effective for BW

275
Q

what did Pasteur do

A

made a vaccine administered to livestock which was effective
BA became a standard organism but needed to be produced locally - the spread of knowledge increased the chance of it being used maliciously
(availability + means of transmission = good BW)

276
Q

what is Glanders

A
  • it is a disease cause by burkholedera and is given to horses by germans
  • it can also affect other animals and sometimes humans
  • it is difficult to diagnose and often fatal
    it is multifactorial - infection types - localised, pus forming cutaneous infections, pulmonary infections, bloodstream infections and chronic supportive infections on the skin
  • no vaccine, no diagnostic, no antibiotic
277
Q

why did none of the horses infected with burkholedera by the germans die

A

because they only developed a cutaneous infection

278
Q

describe the French BA bombs

A

they failed to develop effective inhalation formulations and relied on cuts and lesions for cutaneous infection
planes weren’t sophisticated enough and there were difficulties making vapour clouds

279
Q

what is woolsorter’s disease

A

it occurs when wool sorters inhale BA
the wool contained the spores and there were vapour clouds in the factories due to poor ventilation which lead to inhalation anthrax
people either got flu like or severe symptoms (death)

280
Q

what is the british BW programme

A

they developed new strains and aerosol testing apparatus was developed
they could deliver fixed amounts of spores (not clumps) of different sizes and volumes and test using the new apparatus
many workers died from anthrax

281
Q

what is the softer version of BA

A

Bacillus subtilis

282
Q

what is the human LD50 for BA

A

based on primate data

2500 –> 55000 spores inhaled to be lethal

283
Q

viruses have poor transmission as a BW agent without a ……..….. ………………

A

carrying agent

284
Q

what is salmonella typhimurium and how was it used in BW

A

gram -ve bacteria that spreads in contaminated food e.g. contaminated salad bars in Dallas - could’ve been more effective with more potent strain

285
Q

describe the amerithrax situation

A

letters sent from Washington contained dried spores of anthrax and had code in them likely to be from a scientist
it was a homegrown attack by a forensic scientist
it was an ames strain - radiocarbon dating established it was cultured <2y before mailings
north east water source used
sequencing showed mutations and they found the flask
suspect worked at government biodefense lab and killed himself

286
Q

is BW as dangerous as nuclear weapons

A

just as dangerous if not more

M&I (5 decks)

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