Indoor Air sciences CSMI Practice Exam

What family of molecules comprise endotoxins, according to Bioaerosols?

1. Lipopolysaccharides

2. MRSA

3. Fungal glucan

4. Gram negative

The correct answer is: Lipopolysaccharides

Endotoxins are primarily composed of lipopolysaccharides (LPS), which are large molecules made up of a lipid portion and a polysaccharide portion. These molecules are found in the outer membrane of Gram-negative bacteria. When these bacteria die and disintegrate, they release LPS into the surrounding environment, which can trigger strong immune responses in humans and animals. This characteristic makes endotoxins significant in the study of bioaerosols, especially in relation to indoor air quality and health impacts. Understanding the composition of endotoxins as lipopolysaccharides is crucial because it allows researchers to identify and measure these substances when investigating microbial contamination in various environments. The other options represent different biological entities or classifications that do not accurately define what endotoxins are made of. For example, MRSA refers to a specific strain of bacteria resistant to antibiotics, while fungal glucans pertain to a different group of compounds found in fungi, and "Gram negative" describes a category of bacteria that includes many producers of endotoxins but is not a specific molecular composition.