Question | Answer |
What does a bacterial cell membrane lack? | Sterols such as cholesterol |
What are the functions of the bacterial capsule? | -Protection from dessication - Promoting virulence - Source of nutrition in starvation |
What are the possible functions of the mesosomes? | -Compartmentalisation of DNA -Increase surface area for respiratory enzymes |
What class of flagella are the fastest? | Monotrichous |
What class of flagella are uniformly distributed across the cell? | Peritrichous |
What are the functions of pili? | -conjugation -attachment sites for bacteriophage -attachment to other bacteria (biofilms) |
What is the main component of the bacterial cell wall? | Peptidoglycan |
What class of bacteria have a lipopolysaccharide layer? | Gram negative |
How do we classify/test the difference in chemical complexity of the bacterial cell wall? | Gram staining |
What is the primary stain in a gram stain? | Crystal violet |
What is the mordant in the gram stain? | Iodine |
What is the decolouriser in the gram stain? | Acetone |
What is the counter stain in the gram stain? | Safranin |
What are the three growth factors that bacteria need? | -Vitamins -Amino acids -Purines/Pyrmidines |
What are autotrophs? | Use CO2 as their main source of carbon |
What are heterotrophs? | Take in nutrients in preformed states |
What are phototrophs? | Use light as their main source of energy |
What are chemotrophs? | Gain energy by he oxidation of chemical compounds |
What are psychrophile? (Give example of temp range) | Optimum temperature at the lower end of the temp scale and generally below 20 Celsius |
What are mesohpiles? (Include temperature range) | These have similar ptimum temperatures to human cell and grow over a range of about 20-45 Celsius |
What's classification of temperature must human pathogens be? | Mesophiles |
What are Thermophiles? (Include temp range) | Thermophiles have an optimum temperature in the higher end of the temperature scale and have a range that is greater than 45 Celsius |
What are obligate aerobes? | Must have oxygen present to grow |
What are obligate anaerobes? | Must not have oxygen present to grow |
What are facultative anaerobes? | Can grow with or without oxygen, but prefer its presence |
What are aerotolerant bacteria? | Can grow equally well with or without oxygen present |
What are microaerophiles? | Must have very low concentrations of oxygen (2-10%) |
What are osmotolerant bacteria? | Can grow over a wide range of water activity/solute concentration |
What are halophiles? | Require a high concentration of NaCl to grow |
If conditions are favourable for bacterial growth, does sporulation take place? | No |
In conjugation, what does the donor bacterium contain that the conjugating one does not? | F plasmid |