Q:
Name the different arrangements of cocci bacteria.

A:
* Single coccus
* Diplococcus
* Streptococcus
* Tetrad
* Staphylococcus
* Sarcina

Q:
What are the two main shapes that bacteria come in?

A:
Rods and cocci.

Q:
What arrangement of nuclear material do bacteria have?

A:
A single circular chromosome.

Q:
What differentiates gram positive and gram negative bacteria?

A:
The amount of peptidoglycan in the cell wall. Gram negative have less peptidoglycan, are leakier and therefore are easier to decolourise with alcohol/iodine.

Q:
What are the 2 main purposes of the cell wall in bacteria?

A:
* Provides shape
* Prevents rupture

Q:
What is the structure of the cell wall in gram negative bacteria?

A:
* 10 nm thick
* Peptidoglycan (10%)
* Lipopolysaccharide
* Lipoprotein

Q:
What is the structure of the cell wall in gram positive bacteria?

A:
* 15-18 nm thick
* Peptidoglycan (80%)
* Teichoic acid

Q:
True or false? Some bacteria have special capsules enclosing them which prevent them from being phagocytosed.

A:
True.

Q:
What are the four phases (in order) of the bacterial growth curve?

A:
* Lag
* Log
* Stationary
* Death/decline

Q:
Explain the lag phase of the bacterial growth curve.

A:
Bacteria are not ready to reproduce. They have been transferred to a new medium. They need to synthesise new enzymes appropriate to the new environment.

Q:
Explain the log phase of the bacterial growth curve.

A:
Bacteria have an abudant resource supply. They multiply by binary fission which produces an exponential growth pattern.

Q:
Explain the stationary phase of the bacterial growth curve.

A:
Bacteria are competing for resources. Waste products are beginning to build up. The number of new bacteria is equal to rate of bacteria dying. 

Q:
Explain the death/decline phase of the bacterial growth curve.

A:
Resources have been mostly used up. Waste products are reaching toxic levels. The number of bacteria deaths exceeds the number of new bacteria.

Q:
What selective medium is commonly useed to grow yeasts and fungi?

A:
Sabouraud's medium.

Q:
What are the salient properties of Sabouraud's medium?

A:
High concentrations of glucose. Low pH.

Q:
How is chocolate blood agar made?

A:
The red blood cells are added to the agar when it is hot causing the cells to lyse.

Q:
What are the salient properties of MacConkey Agar?

A:
MacConkey Agar is an indicator medium which is red in the presence of lactose fermenters. It contains biles salts.

Q:
What is an aerobic bacterium?

A:
A bacterium that requires 20% oxygen (atmospheric).

Q:
What is an anaerobic bacterium?

A:
A bacterium that has no requirement for oxygen.

Q:
What is a microaerophilic bacterium?

A:
A bacterium that requires oxygen at less that 20% (atmospheric).

Q:
How are anaerobic bacteria commonly grown in the laboratory?

A:
The cultures are placed inside a air tight vessel that contains oxygen consuming chemicals (e.g. sodium bicarbonate and sodium borohydride). 

Q:
What are 5 major criteria used in the identification of bacteria?

A:
* Gram stain
* Morphology
* Cultural characteristics
* Biochemical characteristics
* Antigenic differences

Q:
What is a virus?

A:
A submicroscopic parasites that consist essentially of a core of RNA or DNA surrounded by a protein coat. A virus is unable to replicate without a host cell, and hence not typically considered a living organism. 

Q:
What are the 6 major steps in the life cycle of a virus?

A:
* Attachment
* Penetration
* Biosynthesis
* Maturation
* Assembly
* Release

Q:
What are the 3 major ways of growing virii in the laboratory?

A:
* Tissue culture
* Eggs
* suckling mice