1.1 Intro Flashcards
What are the several types that microorganisms can be divided into ?
- bacteria
- archaea
- fungi
- helminths + parasites
- protozoa
- algae
Name 2 ‘not technically microorganisms but can be pathogens’
- prions
- viruses
Prokaryotes are :
1. organism cell type ?
2. lack of what ?
3. 2 examples ?
- unicellular
- membrane-bound nucleus & other specialised organelles
- bacteria and archae
Eukaryotes:
1. organism cell type ?
2. cells contain ?
3. 5 examples
- unicellular / multicellular
- nucleus, other membrane-bound organelles
- fungi, algae, protozoa, helminths, parasites
How is bacteria often named by?
Genus and species
Genus species -> S. aureus
3 main characteristics used for classification of bacteria:
- cell morphology (shape)
- staining properties
- oxygen requirement
- All bacteria can be divided into 2 groups which are ?
- what are the differences between the 2 groups due to ?
- gram negative or positive
- structure of the cell wall in the bacteria
Compare gram positive + gram negative bacteria features
1. peptidoglycan layer
2. outer membrane
3. LPS
4. staining colour
5. 2 examples of each
- = thick , - = thin
- = no , - = present
- = no, - = present
- = blue/purple , - = pink/red
- = S.aureus, Streptococci , - = E. coli, salmonella spp
Why are different antibiotics used for different infections ?
structure of peptidoglycan cell wall
Why is it important to know if the bacteria causing an infection is gram negative or gram positive ?
different antibiotics are used fot different infections due to structure of peptidoglycan cell wall
- Gram staining involves a series of …. that dye bacterial cells
- this includes … ?
- sequential steps
- crystal violet, iodine, alcohol and safranin
Why do gram positive bacteria appear purple under the microscope ?
- due to thick peptidoglycan layer in cell wall
- retain the crystal violet-iodine complex
Why do gram negative bacteria appear pink ?
they lose the stain (crystal violet-iodine complex) due to thin peptidoglycan layer in their wall and appear pink after counterstaining with safranin
Based on bacterial susceptibility patterns what does gram staining help guide with ?
antibiotic selection and treatment
3 examples of cocci (spherical) bacteria
- staphylococcus aureus
- streptococcus pneumoniae
- neisseria gonorrhoeae
3 examples of bacilli (rod shaped) bacteria
- escherichi coli
- bacillus anthracis
- pseudomonas aeruginosa
3 examples of spiral bacteria
- treponema pallidum
- campylobacter jejuni
- helicobacter pylori
aerobic bacteria microorganisms that require ?
oxygen to grow and survive
examples of aerobic bacteria (require oxygen to grow and survive)
- mycobacterium tuberculosis
- pseudomonas aeruginosa
anaerobic bacteria =
1. organisms that can survive and grow in ….
2. obtain energy through ?
- absence of oxygen or with very low oxygen levels
- fermentation or anaerobic respiration
4 examples of anaerobic bacteria ?
- clostridium botulinum
- bacteriodes fragilis
- fusobacterium spp
- prevotella spp
Environment that faculative anaerobic can grow in ?
both oxygen-rich (aerobic) and oxygen-poor (anaerobic)
2 examples of faculative anaerobic bacteria
- escherichia coli
- staphylococcys aureus
Bacteria reproduce by ?
binary fission
What is binary fission as a process which does what ?
one parent cell divides to form 2 progeny cells
why are bacteria said to undergo exponential growth (logarithmic growth)?
because one cell gives rise to 2 progeny cells
what are the 4 major phases of growth cycle of bacteria ?
- lag phase
- log phase
- stationary phase
- death phase
what happens in lag phase of bacterial growth cycle ? & how long does it last ?
- vigorous metabolic activity , but cells don’t divide
- can last few minutes up to many hours
what happens in log (logarithmic) phase of bacterial growth cycle ?
rapid cell division occurs
Stationary phase occurs when….
…1…. or toxic products cause growth to …2… until the number of new cells produced ..3… the number of cells that die resulting in a …4…
- nutrient depletion
- slow
- balances
- steady state
What is death phase of bacterial growth cycle marked by ?
decline in the number of viable bacteria
Fungi are ..1… that can cause a number of diseases.
Often associated with ..2… infections in people with ..3.. immune systems.
- eukaryotes
- opportunistic
- compromised
Fungi include ? what’s difference ?
- yeast, bud like, unicellular
- molds, multicellular
don’t complex with lectures after 1.1!
5 examples of diseases caused by fungi ?
- ringworm
- athlete’s foot
- pneumonia
- candidiasis
- aspergillosis
Yeast are…:
1. fungi type ?
2. typically reproduce by ?
3. typicaly shape ?
- unicellular
- budding or fission
- round to oval
Candida albicans is a ..1… species that can cause infections in humans , particularly in ..2… individuals
- yeast
- immunocompromised
examples of infections caused by fungi yeast species
- genital candidiasis
- oral thrush
- candidemia
molds:
1. fungi type ? (unicellular / multicellular )
2. characterised by ?
- multicellular
- presence of filamentous structures called hyphae
Hyphae can be ..1.. or ..2.. (aseptate)
& septate definition
- septate
- nonseptate
septate = divided into compartments by cross-walls called septa
- Helminths are ..1.. organisms, can be ..2… or …3… These are often referred to as ‘..4..’.
- Examples include ..5.., ..6.., …7…
- large, multicellular
- free-living
- parasitic
- worms
- tapeworms
- hookworm
- pinworms
Protozoa are…
* …1… eukaryotes
* they live either ..2.. or ….3…
- single celled
- free-living
- parasitic
A number of protozoa are pathogens causing disease such as , name 4 diseases …
- malaria
- toxoplasmosis
- cryptosporidiosis
- trichomoniasis
What are the requisite characteristics of living organisms that scientists generally agree on ?
1. they have one or more ….
2. they are able to ….
3. they are capable of ….
- cells with DNA
- sense & respond to the environment.
- reproducing, growing, and developing
- capturing & using energy & raw materials
- evolving over generations
what is a prion ?
a infectious misfolded protein
Example of diseases caused by a prion ?
- Creutzfeldt-Jakob disease (CJD)
- kuru in humans
What are the diseases CJD and kuru in humans also called ?
transmissible spongiform encephalopathies
a group of rare, fatal brain disorders that affect both humans and animals
In transmissible spongiform encephalopathies what does the term spongiform refer to ?
sponge-like appearance of the brain
What is configuration when prions are in normal state and are nonpathogenic ?
alpha-helix
alpha-helix , beta-pleated sheet
difference between prions depending on which configuration they are in ?
- alpha-helix = nonpathogenic, normal
- beta-pleated sheet = aggregate into filaments, disrupts neuronal function resulting in the symptoms of disease
What do prions not contain ?
any nucleic acids such as DNA or RNA
What causes the protein to misfold ?
It’s unknown
What can prion disease be either of?
- sporadic
- genetic
- acquired
How rare is CJD acquired by exposure ?
extremely rare
What has CJD been linked to ?
- blood transfusions
- contaminated instruments in brain surgery
- infected tissue transplants
Because prions are not normal human proteins what don’t they elicit in humans ?
an inflammatory response or an antibody response
What are viruses not ?
living organisms
What do viruses consist mainly of?
- short strands of genetic materials (RNA or DNA) encapsulated within a protein coat
What do viruses require in order to replicate ?
a living host cell
What are almost all viruses ?
pathogenic
All viruses have a protein coat called a …1… that covers the genome (…2…)
- capsid
- nucleocapsid
In some viruses what is the capsid (virus protein coat) covered with ?
lipoprotein envelope
What are the two main types of symmetry found in viruses?
- spherical (icosahedral)
- rod helical
What does the baltimore classification classify viruses based on?
their manner of mRNA synthesis
Viruses can be classified according to whether their viral genome is what ?
made of DNA or RNA
Steps involved in viral growth cycle ?
- adsorption
- penetration
- uncoating
- early transcription
- early translation
- DNA synthesis and late transcription
- late translation
- assembly
- release of virus and lysis of infected cell
list examples of DNA viruses & name a disease involved with it:
- Herpes Simplex Virus (coldsore, herpes)
- Varicella-Zoster virus (chickenpox)
- Hepititis B virus (Hepatitis )
- human papillomavirus (HPV)
- Epstein-barr virus (EBV)
- Cytomegalovirus (CMV)
list examples of RNA viruses & examples of diseases involved with it
- HIV (HIV, AIDS)
- influenza virus (influenza)
- coronovirus (covid-19, SARS, MERS)
- rhinovirus (common cold)
- hepatitis C virus
- norovirus
- dengue virus
Microorganism that escherichia coil is ?
Bacteria
Microorganism that staphylococcus aureus is ?
Bacteria
Microorganism that pseudomonas aeruginosa is ?
Bacteria
Microorganism that cryptococcus neoformans is ?
Fungi
Microorganism that candida albicans is ?
Fungi
Microorganism that aspergillus fumigatus is ?
Fungi
Microorganism that trichomonas vaginalis is ?
Protozoa
Microorganism that plasmodium spp is ?
Protozoa
Microorganism that toxoplasma gondii is ?
Protozoa
5 groups of basic shapes of bacteria ?
Spherical (cocci)
Rod (bacilli)
Spiral (spirilla)
Comma (vibrios)
Corkscrew (spirochaetes)
