Microorganisms and Infections Flashcards
Mycoplasma -
Important feature and disease
Important feature: Lacks cell wall
Disease - Pneumonia
Virus - living cell or not ?
Not a living cell - cant replicate unless present in a living cell
List 2 types of Fungi with 3 points
- Candida albicans
- A yeast
- Unicellular
- Reproduce by budding - Aspergillus fumigatus
- A mould
- multicellular
- Reproduce by spores
What is Plasmodium falciparium
Protozoa
is a malaria parasite
What are Helminths and give 2 examples
Eukaryotic cells like Protozoa and Fungi.
Example
- African eye worms
- beef Tape worm
What is taxonomy
Classification of organism
How are organisms named
Binomial nomenclature:-
Genus (like surname) first
Species (like given name) second
In italics or underlined
Are bacteria prokaryotes of Eukaryotes
Prokaryotes
List 5 differences between a Prokaryotic cell and a Eukaryotic cell
Prokaryotes vs Eukaryotes
No nucleus/membrane bound organelles vs membrane bound nucleus
Haploid vs Diploid
single circular DNA vs chromosome in nucleus
70S ribosome (30S and 50S subunits) vs 80S ribosome (40S and 60S subunits)
Peptidoglycan cell wall vs No cell wall (except plant and fungi)
Bacteria morphology
List 2 ways bacteria are classified
- by their Shape
2. Staining
List 5 bacteria morphology shapes
- Round - Coccus
- Long - Bacilli
- Branched - filamentous
- Spiral- spirillum/spirochete
- Comma- Vibro
Staining depends on
How much peptidoglycan is present in the cell wall
List the 5 stages of staining and the end results
- Fixation
- Crystal violet
- Iodine
- Ethanol (Decolorization)
- Safranin
If Pink = Gram negative
if Purple = Gram positive
Match the following
Clusters, Chain, Strepto-, Staphylo-
Clusters = Staphylo- Chains = Strepto-
3 types of bacteria based on atmosphere
- Anaerobes
- Anaerobes
- Facultative anaerobes- (can switch between aerobic and anaerobic metabolism)
List 3 bacterial growth requirements
- Temperature
- Salt content
- pH
Name 2 examples of Gram positive cocci bacteria
- Staphylococcus aureus
2. Streptococcus pyogenes
Name and example of Gram negative bacilli bacteria
Clostridium difficile
Name an example of Gram negative cocci bacteria
Neisseria meningitidis
Neisseria gonorrhoea
Name 3 examples of Gram negative bacilli
Enterobacteriacie
- Salmonella & shigella
- E. Coli
- Klebsiella & Enterobacter
Name 2 bacteria without cell walls
- Mycoplasmas-Mycoplasma Pnuemoniae
2. Chlamydia- Chlamydia trachomatis
Name a bacteria that has a cell wall but does not stain well with Gram stains
Mycobacteria
List 3 structures present in Gram positive bacteria
- Thick peptidoglycan cell wall
- Teichoic acid
- Lipoteichoic acid
List 5 structures present in a Gram negative bacteria
- Lipopolysaccharide (on the outer membrane)
- Porin
- O specific chains
- Thin peptidoglycan wall (between the membranes)
- Integral proteins (between the bilayer)
What is the main job of lipopolysaccharide
Endotoxin
Endo means ‘part of’
List 3 features of a Peptidoglycan cell wall
- N-acetylated sugars
- glucosamine(NAG) and muramic acid (NAM) - 3-5 amino acid peptides
- Transpeptidase enzymes (involved in cell wall synthesis)
list 3 steps involved in the synthesis of peptidoglycan
- Polymerisation of sugar (NAM and NAG)
- Elongation of aa (add peptides)
- Cross link transpeptidase
Why cant Mycobacteria be stained and what other feature enables its survival
Its peptidoglycan is protected by an outer membrane called Myco-membrane/mycolic membrane. Prevents crystal violet from going into the bacteria. It also allows mycobacteria to be anti-phagocytic.
List 2 disease caused by Mycobacteria
- Tuberculosis
2. Leprosy
List 6 important features of bacteria
- Capsule
- Spores
- Ribosomes
- Peptidoglycan cell wall
- Lipopolysaccharides (in Gram negatives)
- Mobile genetic elements (Plasmids and transposons-move location in genome)
Plasmids and transposons are mobile genetic elements that codes for toxins and antibiotic resistance genes. True or False
True
Endo spores in some bacteria enables it to develop resistance to…
List 4 processes
- Drying
- Temperature
- Disinfection
- Digestion
List the 4 stages in bacterial growth
- The lag phase (bacteria adapting to new environment)
- The Exponential phase
- The Stationary phase (nutrients in cells become depleted, division stops)
- Death phase (exhaustion of resources)