Microbiology Quiz: Cells and Techniques

<p>Typically &lt; 5µ (C)</p> Signup and view all the answers

<p>Chemostat (A)</p> Signup and view all the answers

<p>Flow rate divided by volume (C)</p> Signup and view all the answers

<p>Time taken to reduce microbial population by half (B)</p> Signup and view all the answers

<p>Time-consuming process (A)</p> Signup and view all the answers

<p>Escherichia coli (C)</p> Signup and view all the answers

<p>Peptidoglycan (B)</p> Signup and view all the answers

<p>It interferes with transpeptidation for peptidoglycan. (D)</p> Signup and view all the answers

<p>Endospores (A)</p> Signup and view all the answers

<p>Diphtheria (B)</p> Signup and view all the answers

<p>Colony-forming unit (D)</p> Signup and view all the answers

<p>Photoautotrophs, Photoheterotrophs, Chemoautotrophs, Chemoheterotrophs (D)</p> Signup and view all the answers

<p>Capsid (A)</p> Signup and view all the answers

A rigid structure that gives bacteria its shape and protects it from osmotic pressure.

Lysozyme breaks down the β-1, 4 linkage between NAM and NAG in peptidoglycan, disrupting the bacterial cell wall structure, leading to lysis.

Dipicolinic acid is a unique chemical found in bacterial endospores that helps them resist harsh conditions.

Viral capsid is the protein shell surrounding the genetic material of a virus. It protects the viral genome and helps attach to host cells.

PFU (plaque-forming unit) is a measure of viral infectivity, while CFU (colony-forming unit) measures bacterial growth in a culture.

Heterotrophs obtain their energy by consuming other organisms or organic matter. Decomposition is the breakdown of dead organisms and waste material.

Photoautotrophs use light energy to convert inorganic compounds into organic matter. Photoheterotrophs use light energy but need organic compounds as a carbon source.

Chemoautotrophs obtain energy from oxidizing inorganic compounds to make organic matter. Chemoheterotrophs get energy from oxidizing organic compounds consumed.

Bacteria, Viruses, Fungi, Protozoa, Microalgae.

Eucaryotic cells have a nucleus, membrane bound organelles, larger ribosomes, and undergo mitosis/meiosis for cell division. Procaryotic cells lack a nucleus, membrane bound organelles, have smaller ribosomes, and divide via binary fission.

Differential staining is a technique used to differentiate different types of bacteria based on their cell wall properties. The Gram stain is a classic example.

The decimal reduction time (D value) is the time required to reduce the population of microorganisms by 90% (one log cycle) at a specific temperature. It is calculated by measuring the time it takes for a microbial population to decrease by 90% at a constant temperature.

A chemostat is a continuous culture system where fresh medium is continuously added while a portion of the culture is removed. This maintains a steady state of growth.

A hemocytometer is a specialized slide used to count cells directly under a microscope. It has grid lines that divide the area into smaller squares. This method can be time-consuming and requires accurate cell distribution.

The dilution rate in a chemostat is the rate at which fresh medium is added relative to the volume of the culture. It's used to control the specific growth rate of the microorganisms.

Heat sterilization in an autoclave typically takes place at 121 °C (249 °F) for 15-20 minutes at a pressure of 15 psi.