Question 1

The use of filtration for sterilization

Accepted Answer

Filtration can remove viruses, as they are often smaller than bacteria and can pass through traditional sterilization methods such as autoclaving. Filtration uses physical barriers to trap and remove particles, including viruses, from a solution or gas.

Question 2

Which of the following is not true of glutaraldehyde?

Accepted Answer

Glutaraldehyde is classified as a hazardous substance and can cause skin and eye irritation. However, it is not classified as a carcinogen.

Question 3

Which of the following is not a factor that affects germicidal activity?

Accepted Answer

All of the choices listed are factors that affect germicidal activity. Each factor must be considered when choosing the appropriate germicide to use in a particular situation. Therefore, none of the choices listed can be excluded as a factor.

Question 4

All of the following pertain to hypochlorites except

Accepted Answer

Hypochlorites are not found in iodophors. Iodophors contain iodine and are used as disinfectants.

Question 5

All of the following are phenols or phenolics except ______.

Accepted Answer

Zephiran is a quaternary ammonium compound, not a phenol or phenolic. The other options are all classified as phenols or phenolics.

Question 6

_____ solution was introduced in the late 19th century for preventing gonococcal infections in a newborn's eyes after exposure to the mother's infected birth canal.

Accepted Answer

Silver nitrate solution was widely used in the late 19th century as a prophylaxis against gonococcal infections in newborns. It was applied to the eyes of the newborn immediately after birth to prevent infection from the mother's birth canal. However, due to its side effects such as chemical conjunctivitis and corneal damage, it was later replaced by antibiotic ointments.

Question 7

Which of the following germicides is/are also sporicidal?

Accepted Answer

Betadine, chlorine, and chlorhexidine are all known to be effective germicides and sporicidal agents. Phenolics, on the other hand, are not typically potent enough to kill spores.

Question 8

Hydrogen peroxide is

Accepted Answer

Hydrogen peroxide has broad-spectrum efficacy against spores, fungi, bacteria, and viruses, making it effective against a wide range of microorganisms.

Question 9

The compound that is an organic base containing chlorine and two phenolic rings, and is used increasingly for wound degerming, neonatal washes, hand scrubbing, and prepping surgical skin sites is ______.

Accepted Answer

Chlorhexidine is an organic base containing chlorine and two phenolic rings. It is used increasingly for wound degerming, neonatal washes, hand scrubbing, and prepping surgical skin sites.

Question 10

HEPA filters are used to remove microbes from

Accepted Answer

HEPA filters are specifically designed to remove microbes from the air. They are commonly used in air filtration systems in hospitals, laboratories, and clean rooms. While they may also be used in some liquid filtration applications, their primary purpose is air filtration. They are not used to remove microbes from human tissues or medical instruments.

Question 11

All of the following act as surfactants except ______.

Accepted Answer

Iodine is an antiseptic agent and does not have surfactant properties. The other options listed act as surfactants.

Question 12

_____ is a control method that removes microorganisms rather than inhibiting or killing them.

Accepted Answer

Filtration is a control method that physically removes microorganisms from liquids or gases by passing them through a filter with pores small enough to capture the microorganisms.

Question 13

_____ is a halogen used in gaseous and liquid form for large scale disinfection of drinking water and sewage.

Accepted Answer

Chlorine is commonly used for disinfection of drinking water and sewage on a large scale. It is available in both gaseous and liquid form and is effective against a wide range of microorganisms.

Question 14

Which of the following is not used as an antiseptic?

Accepted Answer

Aqueous glutaraldehyde is primarily used as a disinfectant and sterilizing agent, not as an antiseptic.

Question 15

Which of the following is not a heavy metal?

Accepted Answer

Tincture of iodine is not a heavy metal; it is a solution containing iodine in alcohol, used as an antiseptic.

Question 16

Alcohols

Accepted Answer

All of the choices are correct. Alcohols can denature proteins, disinfect items through soaking, act as skin degerming agents, and dissolve cell membrane lipids at concentrations of 50% or higher.

Question 17

Iodophors include ______.

Accepted Answer

Iodophors are compounds that contain iodine and a solubilizing agent, usually an organic compound. Betadine is a commonly used iodophor for antiseptic purposes. Chlorhexidine, alcohols, chloramines, and tincture of iodine are not iodophors.

Question 18

Which of the following is not true of chloramines?

Accepted Answer

Chloramines do not form trihalomethanes with organic compounds; this is a characteristic of free chlorine.

Question 19

The chemical agent/s that produce/s highly reactive hydroxyl-free radicals and also decomposes to O₂ gas is ______.

Accepted Answer

Hydrogen peroxide is known to produce highly reactive hydroxyl-free radicals and also decomposes to O₂ gas.

Question 20

Heavy metals work by

Accepted Answer

Heavy metals such as lead, mercury and cadmium tend to bind with proteins, including enzymes, which leads to inactivation of these proteins. This disruption of protein function can negatively impact cellular processes and eventually lead to cell death.

Quiz 11: Physical and Chemical Control of Microbes