Advanced Microbial Physiology and Structure Quiz

When the magnification of objective lenses increases, the working distance decreases because higher magnification requires the lens to be closer to the specimen in order to focus properly.

The longer wavelength of light makes it more difficult to achieve a higher resolution, hence resolution is worsened with longer wavelengths.

Prions are unique infectious agents that are composed solely of protein and are known to cause neurodegenerative diseases.

Acid-fast organisms like Mycobacterium tuberculosis have a unique cell wall composition that includes high concentrations of mycolic acid, a type of lipid. This lipid content helps these organisms resist decolorization by acid-alcohol wash during staining procedures.

Basic dyes are positively charged and are commonly used in dyeing materials that have a negative charge, such as acrylic, silk, and wool. The positive charge of basic dyes allows them to bond with the negatively charged materials.

In the field of microbiology, Carl Woese initiated ribosomal RNA studies that played a crucial role in differentiating Bacteria and Archea, leading to a better understanding of evolutionary relationships among organisms.

The correct answer refers to the specific type of bonding that occurs in the crosslinking of peptidoglycan in Gram positive organisms.

Diaminopimelic acid is a unique amino acid primarily found in the cell walls of bacteria, specifically in the gram-negative bacteria.

In the peptidoglycan of a Gram negative organism, the crosslinking between the D ala of one tetrapeptide and the Diaminopimelic Acid of a second tetrapeptide occurs through a direct link via an amide bond. This covalent bond plays a crucial role in maintaining the structural integrity of the cell wall.

Spirochetes are known for their twisting and flexing locomotion, which is facilitated by periplasmic flagella (axial filaments) located between the cytoplasmic membrane and outer membrane. Cilia, glycocalyces, and pili are structures found on other types of bacteria but do not contribute to the specific locomotion of spirochetes.

Endospores are a unique type of cell that are produced by certain bacteria to survive extreme conditions by remaining dormant until more favorable conditions arise.

Archaeal plasma membranes are unique in that they may consist of a single lipid monolayer, unlike the double lipid bilayer found in eukaryotic cell membranes. Additionally, they typically lack cholesterol molecules commonly found in eukaryotic cell membranes.

Peptidoglycan is a key component of bacterial cell walls and can be targeted by lysozyme, an enzyme that breaks down its structure.

Aerotolerant anaerobes are organisms that can survive in the presence of oxygen but do not utilize it for growth. Facultative anaerobes can switch between aerobic and anaerobic metabolism, obligate anaerobes cannot survive in the presence of oxygen and microaerophiles prefer low oxygen environments.

Bacteria are most susceptible to antibiotics during the exponential (log) phase of growth because this is when they are actively dividing and synthesizing new cell components, making them more susceptible to the effects of antibiotics that target processes involved in cell division and growth.

Microbial growth factors generally refer to essential nutrients required by microorganisms for growth and reproduction. While carbohydrates, proteins, and lipids are major classes of microbial growth factors, nucleic acids are not typically classified as such.