Question 1

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. The material being treated, length of exposure, strength of the germicide, and the specific microorganism being treated all play a role in determining the effectiveness of a germicidal agent.

Question 2

All of the following act as surfactants except ______.

Accepted Answer

Surfactants are substances that reduce the surface tension between two liquids, or between a liquid and a solid. Detergents, soaps, quaternary ammonia, and alcohols all act as surfactants. Iodine, however, does not have surfactant properties.

Question 3

Which of the following is not true of chloramines?

Accepted Answer

The answer of Which of the following is not true...

Question 4

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

Accepted Answer

The chemical agent/s that produce/s highly reactive hydroxyl-free radicals is hydrogen peroxide. It also decomposes to oxygen and water, not O₂ gas. Chlorhexidine, iodophors, cationic detergents, and Cidex do not produce hydroxyl-free radicals or decompose to O₂ gas.

Question 5

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

Accepted Answer

The answer of _____ is a control method that removes...

Question 6

_____ 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 due to its high reactivity and effectiveness in killing microorganisms. It can be applied in gaseous or liquid form and is widely considered to be one of the most cost-effective disinfectants available. Iodine and bromine are also halogens frequently used for disinfection, but they are typically more expensive and less effective than chlorine. Fluorine is not used for this purpose at all, and betadine is typically used as a topical antiseptic rather than a disinfectant for water or sewage.

Question 7

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

The answer of The compound that is an organic base...

Question 8

_____ 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 was introduced in the late 19th century as a prophylactic treatment for gonococcal infections in newborns' eyes after exposure to the mother's infected birth canal. This treatment fell out of favor in the mid-20th century due to concerns about irritant effects on the eyes and the possibility of developing chemical conjunctivitis. It has since been replaced by safer and less irritating treatments such as erythromycin ointment or povidone-iodine solution.

Question 9

HEPA filters are used to remove microbes from

Accepted Answer

HEPA filters are typically used to clean air by filtering out microscopic particles such as dust, pollen, and even microbes like bacteria and viruses. They are not commonly used for filtering liquids or other materials.

Question 10

Heavy metals work by

Accepted Answer

Heavy metals like lead, mercury, cadmium, and arsenic work by binding to proteins or enzymes in the cell, which can inactivate or modify them, disrupting normal cellular function. This can lead to a wide range of health problems and toxic effects. Therefore, option D is the best choice as it describes one of the primary mechanisms by which heavy metals exert their toxic effects.

Question 11

Which of the following germicides is/are also sporicidal?

Accepted Answer

Betadine, chlorine, and chlorhexidine are all sporicidal in addition to being germicidal. Phenolics are not reliably sporicidal.

Question 12

The use of filtration for sterilization

Accepted Answer

Filtration is a common method used for sterilization of liquids that cannot withstand heat. It involves the use of a filter with pores smaller than the size of microorganisms like bacteria and fungi. Filtration is an effective method of removing viruses from liquids as well since viruses are much smaller than bacteria and fungi. Hence, option E) can remove viruses is the best choice. Option A is incorrect because filtration does not leave behind endospores since endospores are resistant to most sterilization techniques. Option B is incorrect because filtration may not remove toxins that are smaller than microbial cells. Option C is incorrect because filtration alone does not use heat for sterilization. Option D is incorrect because filtration is not reliant on gravity.

Question 13

Alcohols

Accepted Answer

All of the choices are correct.

Question 14

Iodophors include ______.

Accepted Answer

Iodophors are a type of antiseptic that contains iodine. Betadine is an example of an iodophor. Chlorhexidine, alcohols, and chloramines are not iodophors. Tincture of iodine contains iodine, but it is not an iodophor as it does not contain a carrier molecule.

Question 15

Hydrogen peroxide is

Accepted Answer

Hydrogen peroxide is effective against all of the listed microorganisms: spores, fungi, bacteria, and viruses.

Question 16

All of the following are phenols or phenolics except ______.

Accepted Answer

Zephiran is not a phenol or phenolic. It is a brand name for benzalkonium chloride, a type of quaternary ammonium compound commonly used as a disinfectant. The other choices are all examples of phenols or phenolics.

Question 17

Which of the following is not used as an antiseptic?

Accepted Answer

The answer of Which of the following is not used...

Question 18

Which of the following is not true of glutaraldehyde?

Accepted Answer

Glutaraldehyde is classified as a high-level disinfectant and sterilant, capable of inactivating viruses and endospores within a few hours. It works by cross-linking proteins on cell surfaces, and is commonly used in healthcare settings to disinfect equipment and surfaces. However, it is not true that glutaraldehyde is classified as a carcinogen; while it can cause respiratory and allergic reactions if not handled properly, it is not known to be a carcinogen.

Question 19

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 20

All of the following pertain to hypochlorites except

Accepted Answer

Hypochlorites are not found in iodophors. Iodophors contain iodine, which is a different type of disinfectant.

Quiz 11: Physical and Chemical Control of Microbes