Module 3: Section 2B

Question 1

Chemotherapy

Answer 1

• Use of chemical agents in the treatment of disease
• Ex: Medication like antibacterials and antifungals

Question 2

Biocide

Answer 2

• A chemical or microorganism used to kill, stop, or control harmful organisms.

Question 3

Antisepsis

Answer 3

• Prevention of microorganisms on, or in, living tissue
• Ex: Antimicrobial topical cream

Question 4

Sanitization

Answer 4

• Reduction of total microbial population to levels considered safe by public health standards
• Ex: hand sanitizer

Question 5

Disinfection

Answer 5

• Substantial reduction of total microbial population and destruction of pathogens
• Ex: Disinfecting spray

Question 6

Sterilization

Answer 6

• All living cells, spores, viruses and prions are either destroyed or removed from the treatment environment
• Steam sterilization of medical instruments

Question 7

What is the mechanical method of microbial control?

Answer 7

• Filtration
• removes microbes from liquids or air.
• It can disinfect or sterilize depending on the filter size.

Question 8

What is the chemical method of microbial control?

Answer 8

• Direct exposure to chemicals
• in gas or liquid form
• Can disinfect and sterilize

Question 9

What is dry heat used for in microbial control? (Physical)

Answer 9

• Dry heat (like incineration or an oven) kills microbes
• Sterilizes

Question 10

What is moist heat used for in microbial control? (Physical)

Answer 10

• Moist heat (like steam, boiling water, or pasteurization) kills microbes
• Steam under pressure sterilizes
• Boiling or pasteurization disinfects

Question 11

What is radiation used for in microbial control? (Physical)

Answer 11

• Radiation kills microbes using energy waves
• Ionizing radiation (X-rays, gamma) sterilizes
• UV light disinfects surfaces

Question 12

How can liquid solutions be sterilized?

Answer 12

By passing the solution through a filter with a very small pore size, removing the microbes that are present

Question 13

What does a Biological Safety Cabinet (BSC) provide?

Answer 13

A safe working environment for working with infectious or sterile materials.

Question 14

How is air filter sterilized in a Biological Safety Cabinet (BSC)?

Answer 14

Air entering the cabinet passes through a HEPA filter before reaching the work surface, and air leaving also passes through HEPA filters to prevent contamination.

Question 15

What are chemical agents for control?

Answer 15

• Chemical agents used as biocides can act as sterilants, disinfectants, or antiseptics depending on their effectiveness and concentration.
• They work by denaturing proteins or dissolving membrane lipids.

Question 16

2 examples of sterilient

Answer 16

1. Glutaraldehyde
2. Stabilized hydrogen peroxide

Question 17

2 examples of disinfectant

Answer 17

1. Chlorine compounds
2. Alcohols

Question 18

2 examples of antiseptic

Answer 18

1. Chlorhexidine
2. Triclosan

Question 19

How does heat act as a control agent?

Answer 19

• Most microbes need specific temperatures to grow, and temperatures outside that range damage their structures and chemical reactions
• Moist and dry heat destroy viruses, bacteria, and fungi

Question 20

How are autoclaves used for sterilization?

Answer 20

• Autoclaves use moist heat under pressure, heated to 121°C for at least 20 minutes
• Pressure keeps liquids from boiling above 100°C

Question 21

What does ultraviolet (UV) radiation do?

Answer 21

• UV radiation is lethal and causes thymine-thymine dimerization of DNA, stopping replication and transcription
• It has low penetrating power and is used to sterilize surfaces and treat drinking water

Question 22

What does ionizing radiation do?

Answer 22

• Ionizing radiation penetrates deeply and forms damaging free radicals that react with matter
• The WHO says irradiated food is safe for human consumption