13.2

Question 1

Thermal death point

Answer 1

The lowest temperature at which all microbes are killed in a 10-minute exposure

Question 2

Thermal death time

Answer 2

The length of time needed to kill all microorganisms in a sample at a given temperature

Question 3

Dry-heat sterilization

Answer 3

Direct application of high heat. Can be applied for long periods of times.

Question 4

Moist-heat sterilization

Answer 4

More effective protocol because it penetrates cells better than dry heat does. Raise temperatures above the boiling point of water to sterilize items.

Question 5

Who designed the modern autoclave

Answer 5

Charles Chamberland while working with Louis Pasteur.

Question 6

Retorts

Answer 6

Larger autoclaves used for large-scale sterilization out of laboratory and clinical settings.

Question 7

Heat-sensitive autoclave tape

Answer 7

Turn black when appropriate temperature is achieved. Does not help with length of exposure so cannot indicate sterility.

Question 8

Biological indicator spore test

Answer 8

Strip of paper or a liquid suspension of the endospores to determine whether the endospores are killed by the process.

Question 9

Pasteurization

Answer 9

Used in food. Kills pathogens and reduces the number of spoilage-causing microbes while maintaining food quality.

Question 10

high-temperature short-time pasteurization

Answer 10

exposes milk to a temperature of 72 degrees for 15 seconds which lowers bacterial numbers while preserving the quality of the milk.

Question 11

ultra-high-temperature pasteurization

Answer 11

milk is exposed to a temperature of 138 degrees for 2 or more seconds. Can be stored for a long time in sealed containers without being refrigerated.

Question 12

Psychrophiles

Answer 12

prefer cold temperatures

Question 13

0 degrees to 7 degrees

Answer 13

inhibits microbial metabolism, slowing the growth significantly and helping preserve refrigerated products

Question 14

below -2 degrees

Answer 14

may stop microbial growth and even kill susceptible organisms

Question 15

pascalization

Answer 15

high pressure processing in food industry

Question 16

Desiccation or dehydration

Answer 16

drying to preserve foods such as raisins, prunes, and jerky. Does not kill all microbes or their endospores

Question 17

freeze-dying or lyophilization

Answer 17

item is rapidly frozen and placed under vacuum so that water is lost by sublimation. Better than desiccation.

Question 18

water activity

Answer 18

water content of foods and materials

Question 19

Ionizing radation

Answer 19

strong enough to pass into the cell where it alters molecular structure and damages cell components.

Question 20

non ionizing radiation

Answer 20

used for disinfection and uses less energy than ionizing radiation. Does not penetrate cells or packaging.

Question 21

sonication

Answer 21

use of high-frequency ultrasound waves to disrupt cell structures

Question 22

cavitation

Answer 22

formation of bubbles inside the cell, which can disrupt cell structures and eventually cause the cell to lyse or collapse.

Question 23

High-efficiency particulate air filter

Answer 23

effective pore sizes small enough to capture bacterial cells, endospores, and many viruses.

Question 24

hyperbaric oxygen therapy

Answer 24

air pressure three times higher than normal. Inhibits metabolism and growth of anaerobic microbes.