Microbiology Media Techniques Quiz

<p>Microbial species based on metabolic activities (D)</p> Signup and view all the answers

<p>Luria-Bertani Broth (D)</p> Signup and view all the answers

<p>Based on sugar alcohol fermentation (A)</p> Signup and view all the answers

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

<p>To support growth of fastidious organisms (B)</p> Signup and view all the answers

<p>It is ideal for counting colonies due to even distribution. (B)</p> Signup and view all the answers

<p>A process to reduce microbial concentration in a sample. (D)</p> Signup and view all the answers

<p>Potential for cross-contamination. (D)</p> Signup and view all the answers

<p>To avoid errors in determining colony-forming units. (C)</p> Signup and view all the answers

<p>To maintain a pure culture and prevent overgrowth. (C)</p> Signup and view all the answers

<p>The process can be time-consuming. (A)</p> Signup and view all the answers

<p>When counting colonies from a diluted sample. (D)</p> Signup and view all the answers

<p>Cross-contamination may occur. (A)</p> Signup and view all the answers

<p>To isolate individual microbial cells into pure colonies. (A)</p> Signup and view all the answers

<p>To ensure even distribution of microorganisms in the agar. (D)</p> Signup and view all the answers

<p>It allows for accurate colony counting. (A)</p> Signup and view all the answers

<p>Anaerobic organisms. (D)</p> Signup and view all the answers

<p>It is applied in a specific pattern using a sterile spreader. (A)</p> Signup and view all the answers

<p>Pour plate method. (A)</p> Signup and view all the answers

<p>To support the growth of fastidious organisms. (D)</p> Signup and view all the answers

<p>Chocolate Agar (C)</p> Signup and view all the answers

<p>To maintain microbial viability during transportation. (B)</p> Signup and view all the answers

<p>Streak Plate Method (A)</p> Signup and view all the answers

<p>Organisms based on their hemolysis patterns. (C)</p> Signup and view all the answers

<p>They enhance the growth of fastidious organisms. (D)</p> Signup and view all the answers

<p>Stuart's Transport Medium (C)</p> Signup and view all the answers

<p>They require specific nutrients for growth. (D)</p> Signup and view all the answers

<p>Brain Heart Infusion Broth (C)</p> Signup and view all the answers

<p>To isolate pure colonies from a mixed culture. (C)</p> Signup and view all the answers

<p>Ensures continuous growth of pure cultures (C)</p> Signup and view all the answers

<p>-5°C to 15°C (B)</p> Signup and view all the answers

<p>Subject to contamination risks (D)</p> Signup and view all the answers

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

<p>By utilizing fermentation or anaerobic respiration (D)</p> Signup and view all the answers

<p>Slow down metabolic processes (D)</p> Signup and view all the answers

<p>Thermus aquaticus (D)</p> Signup and view all the answers

<p>Aerobic microorganisms (D)</p> Signup and view all the answers

<p>It inhibits microbial growth. (C)</p> Signup and view all the answers

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

<p>Producing compatible solutes (A)</p> Signup and view all the answers

<p>They may experience growth inhibition or cell lysis. (C)</p> Signup and view all the answers

<p>Genetic makeup (D)</p> Signup and view all the answers

<p>Less than 1 mm (D)</p> Signup and view all the answers

<p>It helps in nutrient solubilization. (B)</p> Signup and view all the answers

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

<p>To amplify specific DNA sequences (C)</p> Signup and view all the answers

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

<p>They allow identification without culturing microorganisms (D)</p> Signup and view all the answers

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

<p>Sequencing the entire genetic material of a community (D)</p> Signup and view all the answers

<p>They are crucial for detecting hard-to-grow pathogens (A)</p> Signup and view all the answers

<p>Identifying <em>Mycobacterium tuberculosis</em> (B)</p> Signup and view all the answers

<p>Specific DNA sequences with labeled probes (B)</p> Signup and view all the answers

<p>Smooth, rough, mucoid, flat (B)</p> Signup and view all the answers

<p>The thickness of the peptidoglycan layer (C)</p> Signup and view all the answers

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

<p>Application of crystal violet (B)</p> Signup and view all the answers

<p>Red (D)</p> Signup and view all the answers

<p>Sticky and glistening (D)</p> Signup and view all the answers

<p>It helps narrow down organism possibilities (A)</p> Signup and view all the answers

<p>Straight (D)</p> Signup and view all the answers

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

<p>Color change in the pH indicator (A)</p> Signup and view all the answers

<p>Endospore Stain (D)</p> Signup and view all the answers

<p>Bubbles upon reaction with hydrogen peroxide (B)</p> Signup and view all the answers

<p>Helicobacter pylori (D)</p> Signup and view all the answers

<p>Color change to blue or purple (C)</p> Signup and view all the answers

<p>Clear halo around the cell (B)</p> Signup and view all the answers

<p>Degradation of tryptophan into indole (A)</p> Signup and view all the answers

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

<p>pH between 6 and 8 (B)</p> Signup and view all the answers

<p>They have special mechanisms like proton pumps (A)</p> Signup and view all the answers

<p>They must avoid oxygen to survive (A)</p> Signup and view all the answers

<p>Most microorganisms require moisture for growth (A)</p> Signup and view all the answers

<p>Microbial activity is significantly limited (A)</p> Signup and view all the answers

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

<p>0.9 (B)</p> Signup and view all the answers

A type of media used to determine if microorganisms produce specific enzymes such as urease or gelatinase. These enzymes can affect how microorganisms move or grow.

A semi-solid media used to detect if a microorganism is capable of movement. Contains low agar concentration, allowing for movement.

A specific type of culture media that contains chemicals or ingredients to prevent the growth of certain microorganisms while promoting the growth of others. This allows for the isolation of specific groups of organisms from a mixed sample.

A type of media containing ingredients that differentiate between different groups of microorganisms based on their metabolic activities. The media color changes or appearance reflects biochemical reactions inside the microbes.

A type of media that contains additional nutrients like vitamins, amino acids, or blood to support the growth of fastidious organisms - organisms that require specific growth conditions.

Media that inhibits the growth of Gram-positive bacteria while allowing Gram-negative bacteria to grow. Contains bile salts and crystal violet. Commonly used to isolate enteric pathogens.

A type of media selective for Gram-negative bacteria, especially enteric bacteria. Differentiates these bacteria based on their ability to ferment lactose.

A type of media that differentiates microorganisms based on their ability to lyse red blood cells. Hemolytic bacteria lyse red blood cells, while non-hemolytic bacteria do not.

This method involves spreading a diluted sample of microorganisms evenly across a solid agar surface in a petri dish, allowing individual cells to grow into isolated colonies.

A method for isolating microorganisms by diluting a sample and mixing it with molten agar, then pouring the mixture into a petri dish allowing colonies to grow both on the surface and within the agar.

This method involves diluting a sample of microorganisms by repeatedly streaking it across an agar plate, allowing isolated colonies to grow.

These special media have extra nutrients or growth factors that picky microbes need to thrive.

They help keep microbes alive during transport, like a comfy travel pod.

This method uses a streak to thin out a sample, separating individual microbes to form isolated colonies.

Fastidious organisms have specific nutritional needs, like picky eaters.

Chocolate agar contains lysed red blood cells, making it rich for Haemophilus and Neisseria growth.

This broth is a nutritious soup for a wide range of fastidious bacteria and fungi.

Blood agar contains whole blood and helps identify microbes based on how they break down red blood cells.

Stuart's Transport Medium is a common choice for keeping Neisseria gonorrhoeae alive during transport.

Amies Transport Medium is designed for swabs, keeping them moist without encouraging excessive growth.

Transport broth is perfect for transporting fecal samples, wound specimens, and other clinical samples.

A method of successively diluting a microbial sample to reduce the concentration of microorganisms, making it easier to count colonies and isolate pure cultures.

Transferring microorganisms from a culture to fresh growth media to maintain a pure culture and prevent overgrowth.

Individual colonies formed on an agar plate after incubation, representing a single, genetically identical microorganism, originating from a single cell.

The number of CFUs per unit volume of a sample, typically measured as CFUs per milliliter (CFU/mL).

A measurement of microbial concentration in a sample, based on observing how many CFUs are generated when a specific amount of a diluted sample is plated onto an agar plate.

Microbes that thrive in extremely cold environments, like those found in deep oceans and polar regions.

The most common type of microbe, flourishing at moderate temperatures, which includes many human pathogens.

Microbes that thrive in hot environments like hot springs and compost heaps, tolerating temperatures up to 80°C.

Microbes that thrive in extreme heat, often exceeding 100°C, found in volcanic regions and hydrothermal vents.

Microbes that require oxygen for growth and energy production, utilizing cellular respiration.

Microbes that do not require oxygen and can be harmed by it. They utilize alternative energy production methods like anaerobic respiration or fermentation.

The removal of contaminating organisms from a culture to maintain the purity of a specific microbe.

A technique that uses enzymes to amplify specific DNA sequences, allowing for the identification of microorganisms by their unique genetic markers.

A method that sequences the entire genetic material of a microbial community from environmental samples, revealing the diverse range of organisms present.

A technique that involves using labeled probes to detect specific DNA sequences in a sample by hybridization to their complementary sequences.

The sequencing of microbial DNA, such as the 16S rRNA gene for bacteria, provides highly detailed genetic information for identifying organisms at the species level and understanding evolutionary relationships.

These techniques provide highly accurate methods for identifying microbes based on their unique genetic makeup, surpassing limitations of traditional methods.

These techniques are essential for identifying pathogens that are difficult to cultivate or for detecting very low numbers of microbes in a sample.

The ability of molecular techniques to accurately identify microorganisms even when they cannot be directly observed or cultured makes them indispensable for various applications.

Microbial cultures are essential for isolating, identifying, studying, and manipulating microbes, enabling advancements in healthcare, industry, and environmental monitoring.

Colony morphology describes the visible characteristics of bacterial colonies grown on solid media, including color, texture, elevation, and edge. It provides information about the organism's nature and often helps narrow down identification.

The Gram stain is a crucial differential staining technique that classifies bacteria based on their cell wall structure. Gram-positive bacteria have a thick peptidoglycan layer and retain the crystal violet dye, appearing purple. Gram-negative bacteria have a thinner peptidoglycan layer and appear pink after counterstaining with safranin.

Smooth texture refers to a colony's even and shiny surface. It's often observed in bacteria lacking capsules or other surface structures. Rough texture, conversely, indicates an uneven and dull surface, potentially associated with the presence of capsules or other surface irregularities.

Mucoid colonies have a sticky, glistening appearance due to the production of polysaccharides. They typically have a smooth surface and often form raised, dome-shaped colonies.

Colony edge refers to the shape of a colony's outer margin. Smooth edges are rounded, wavy edges are irregular, lobate edges have distinct lobes, and filamentous edges are thread-like.

Microscopic examination with staining techniques allows us to observe bacterial size, shape, arrangement, and other features. Staining methods like Gram staining help distinguish between different types of bacteria.

The Gram stain procedure involves four steps: applying crystal violet, adding iodine, decolorizing with alcohol or acetone, and counterstaining with safranin. The primary stain, crystal violet, is retained by Gram-positive bacteria, resulting in a purple color. Gram-negative bacteria lose the crystal violet during decolorization and are then counterstained pink by safranin.

The Gram stain is important for classifying and identifying bacteria. It provides information about their cell wall structure, which in turn helps in the diagnosis and treatment of bacterial infections.

The amount of water available for microbial growth. Low water activity inhibits microbial growth.

Essential nutrients required in large quantities by microorganisms for cellular structures and energy. Examples include carbon, nitrogen, phosphorus, and sulfur.

Trace elements essential for enzymatic functions, required in small amounts. Examples include iron, magnesium, potassium, and calcium.

Organisms that thrive in high salt concentrations and have adaptations to maintain osmotic balance (e.g., glycerol).

Organisms Tolerate high salt concentrations but don't require them for growth.

Organisms capable of growing in a range of salinities but prefer lower salt concentrations.

The visual characteristics of microbial colonies grown on agar plates. Key aspects include shape, size, and color.

The ability of microorganisms to move independently. It can be detected by specialized media that allows for movement, such as motility test medium.

A staining technique used to identify bacteria that possess a waxy cell wall, making them resistant to decolorization with acid-alcohol.

A biochemical test that identifies organisms based on their ability to ferment specific sugars (e.g., glucose, lactose, sucrose), which is indicated by a color change or gas production.

A biochemical test that checks for the presence of the enzyme cytochrome c oxidase, involved in cellular respiration. A positive test shows a color change (blue or purple) on a paper strip or in a reagent.

A biochemical test that detects the presence of the enzyme catalase, which breaks down hydrogen peroxide into water and oxygen. Bubbles indicate a positive result.

A biochemical test that assesses an organism's ability to produce the enzyme urease, which breaks down urea into ammonia and carbon dioxide. A color change in the medium signals a positive result.

A biochemical test that measures an organism's ability to degrade tryptophan into indole. A positive result shows a red ring upon adding Kovac's reagent.

A staining technique used to visualize the presence of a bacterial capsule. The capsule appears as a clear halo around the cell.

A staining technique used to identify bacterial endospores, which are resistant structures within the cell. Endospores appear green after staining with malachite green.

Organisms that prefer acidic conditions (pH below 6).

Organisms that thrive in alkaline environments (pH greater than 9).

Organisms that can grow with or without oxygen, using aerobic respiration when oxygen is present and anaerobic respiration or fermentation when it's absent.

Organisms needing a low oxygen level for optimal growth, as high oxygen levels are toxic.

The availability of water for microbial growth.

Organisms that require a certain level of water activity (typically >0.9) for optimal growth.

The pH of the environment significantly affects microbial growth. Most microorganisms prefer a neutral pH (around 7), but some thrive in acidic or alkaline environments.

Organisms that must avoid oxygen to prevent the formation of damaging reactive oxygen species.