Microbiology Flashcards
What advantage does having a plasmid often give prokaryotes
Plasmids usually contain genes for antibiotic resistance
How do bacteria reproduce
Binary Fission
How can bacteria be classified
Shape Groupings Gram staining Respiration type Response to nutritional changes
What is the name for spherical bacteria
Cocci/Coccus
What is the name for rod-shaped bacteria
Bacilli/Bacillus
What is the name for spiral shaped bacteria
Spirilli/Sprirllum
What is the name for comma shaped bacteria
Vibria/vibrio
What is the name for bacteria grouped in pairs
Diplo
What is the name for bacteria grouped in clusters
Staphylo
What is the name for bacteria grouped in chains
Strepto
Describe gram+ cell walls
Thick peptidoglycan layer
Describe gram- cell walls
Thin peptidoglycan layer, extra lipopolysaccharide and protein layer
Which type of bacteria retain the Gram test dye and why
Gram positive because they have simpler cell walls that the dye can bind to
Give two examples of gram+ bacteria
Staphylococcus
Streptococcus
Give two examples of gram- bacteria
E-coli
Salmonella
What are obligate aerobes
Only grow in the presence of oxygen as they respire aerobically
What are obligate anaerobes
Only grow where there is no oxygen as they only respire anaerobically
What are facultative anaerobes
These can grow in non oxygen conditions but thrive in oxygen
What are phototrophs
Obtain energy from sunlight and photosynthesise either using water or hydrogen sulfide
What are organotrophs
Oxidise organic compounds eg, glucose
What are lithotrophs
Oxidise inorganic compounds like hydrogen sulfide. Can often synthesise carbohydrates from CO2
Name three methods of counting cells
Haemocytometer
Dilution plating
Turbidity meter/Colorimeter
What type of cell count does a haemocytometer give you
Total count
What type of cell count does a colorimeter/turbidity meter give you
Total count
What type of cell count does dilution plating give you
Viable count
