"Contaminated hospital equipment represents a difficult environment to control harmful microbial growth. Regarding influences that affect disinfection of hospital equipment, which of the following is an accurate statement?
Biofilms, often found contaminating hospital equipment, are relatively simple targets for biocides to reach effectively.
The presence of organic matter, such as dried blood or protein, will not affect the action of antimicrobial agents.
Antimicrobial agents work best under reduced temperatures.
The cell walls of gram-negative bacteria are especially resistant to many chemical that are used to destroy microbes.
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Biofilms are extracellular matrix formed by organisms. They are slimy and are used to attach to surfaces. They are made of polysachharides and form a barrier of protection against disinfectants. Therefore, they make it difficult to decontaminate surfaces.
Organic matter like dried blood or protein also affect the action of antimicrobial agents. Organic matter may form a layer that would reduce the access of the disinfection to the organism.
Antimicrobial agents are affected by temperature and have optimum temperature of action. Some get denatured by heat while some are unaffected. The temperature an antibiotic works will also depend on the organism and its mode of action.
Gram negative bacteria have shown resistance to more antimicrobials.
Gram staining is a staining techniques used for the identification of bacteria in microbiological studies.
Gram staining uses crystal violet as the primary stain. It complexes with the peptidoglycan cell wall of Gram positive bacteria giving them a purple color.
An iodine mordant is also used that forms a crystal violet-iodine complex that fixes the crystal violet dye to the cell wall. This prevents the Gram positive cell walls from being decolorized by the application of alcohol.
A counter stain, safranin is then applied that stains Gram negative bacteria pink.
Lungs expand to pull oxygen into the body and contract to push it back out. The larynx is known as the voice box which is an air way passage to the lungs and a pharanx is membrane lined cavity behind the nose and mouth. Neither of these really expand or contact during inhalation so the answer is Lungs.
