Microbiology Lecture Review Flashcards

Tutorial 5 Crossword Puzzle

Across

[4] Chemical that works better in aqueous solution: This refers to something that is more effective when dissolved in water.
[5] Number of common methods used to test potency of a disinfectant: This is asking for the quantity of standard techniques used to evaluate a disinfectant's effectiveness.
[7] Autoclaves use this type of heat: Autoclaves utilize a specific type of heat for sterilization purposes.
[8] Type of radiation capable of penetrating paper and plastic: This is inquiring about a radiation type with high penetration capabilities.
[11] Another term for dessication: Dessication is a process with a synonymous term.
[12] Type of dimers caused by non-ionising radiation: This refers to a specific type of molecular alteration caused by non-ionizing radiation.
[13] Heavy metal historically used to treat syphilis: A heavy metal that has been used as a treatment for syphilis in the past.
[15] Handwashing is an example of this method of control: Handwashing is a practical illustration of a particular control method.
[19] Lowest temperature at which all microbes are killed in a 10-min exposure is Thermal Death ___: This refers to the concept of thermal death point/time.
[21] What does the P in HEPA filter stand for?: This is an avvreviation question.
[23] Factors which influence of cleanliness: This suggests factors that affect how clean something is.
[24] Types of pasteurisation: This refers to pasteurization techniques.
[25] High concentrations of salt and what else is used for dessication: High concentrations of salt combined with another substance are used for dessication.

Down

[1] Another name for carbolic acid: Asking for an alternative name for carbolic acid.
[2] Type of compound where iodine is complexed with an organic molecule: This describes a compound formed by combining iodine with an organic.
[3] Boiling point of water is higher at higher altitudes. True or False: Statement assessing knowledge of the relationship between altitude and the boiling point of water.
[6] Hyperbaric chambers use which gas in pressurised form: Which gas is used in hyperbaric.
[9] Term used to describe chemicals used for sterilisation: This is asking for the term that describes chemicals used for sterlization.
[10] Term used to denote complete removal or killing: Term used to describe the complete elimination of something.
[14] What do surfactants do to the surface tension of water?: This is asking about the effect of the surfactants on the surface tension of water.
[16] Types of compounds which facilitate slow release of chlorine: This relates to compounds designed for the gradual release of chlorine.
[17] Which heavy metal causes Argyria?: This refers to the heavy metal that causes Argyria.
[18] In an autoclave air is replaced by this: In an autoclave the air gets replaced by another substance.
[20] Type of organisms reduced by pasteurisation: This question asks about the organisms targeted by pasteurization.
[22] Beta-propionolactone is metabolised quickly to this acid: This states that Beta-propionolactone converts into a specific acid.

Viable Counts

Viable counts measure the living, reproducing population of microorganisms.
Counts are performed by observing colonies on plates with an ideal range of 30-300 colonies.
The original sample must be diluted to achieve a countable colony number.

Viable Count Methods

Pour Plate Method: Involves pipetting the inoculum onto a sterile plate, adding sterile medium, swirling to mix, and then incubating. Colonies grow both within and on the medium.
Spread Plate Method: Involves pipetting the inoculum onto the surface of an agar plate, spreading it evenly, and incubating. Colonies grow only on the surface of the medium.

Viable Count Calculation Example

Given: 32 colonies from 0.1 ml spread on a plate, with a 10^4 dilution.
Calculation:
- CFU/ml = \frac{32 \times 10^4}{0.1}
- CFU/ml = 3.2 \times 10^6