Bacterial Growth and Genetic Changes

<p>Cells die and may undergo lysis. (B)</p> Signup and view all the answers

<p>It cannot reliably ascertain cell viability. (C)</p> Signup and view all the answers

<p>Light scattering by cells in suspension (A)</p> Signup and view all the answers

<p>By weighing the dried pellet from concentrated culture. (D)</p> Signup and view all the answers

<p>To correlate optical density to cell concentration for different species. (C)</p> Signup and view all the answers

<p>Both the species and nutritional status (B)</p> Signup and view all the answers

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

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

<p>They require additional supplements to grow. (C)</p> Signup and view all the answers

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

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

<p>It is resistant to ampicillin. (D)</p> Signup and view all the answers

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

<p>To view them under a microscope (D)</p> Signup and view all the answers

<p>They remain colorless (A), They turn pink (B)</p> Signup and view all the answers

<p>The time taken for a cell to divide (D)</p> Signup and view all the answers

<p>To differentiate between cell types (D)</p> Signup and view all the answers

<p>They contain high levels of waxy materials (C)</p> Signup and view all the answers

<p>Acid-fast staining (C)</p> Signup and view all the answers

<p>Increase in number of cells (C)</p> Signup and view all the answers

<p>Stain with malachite green (A)</p> Signup and view all the answers

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

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

<p>It includes special nutrients like blood or serum. (A)</p> Signup and view all the answers

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

<p>Christensen's urease medium (C)</p> Signup and view all the answers

<p>It includes additional ingredients for special nutrients. (D)</p> Signup and view all the answers

<p>To change color when a specific bacterium grows. (C)</p> Signup and view all the answers

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

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

<p>Increased exposure to light (A)</p> Signup and view all the answers

<p>Microscopy, genetic sequencing, and biochemical tests (D)</p> Signup and view all the answers

<p>It detects changes in anaerobic conditions (D)</p> Signup and view all the answers

<p>Optimal conditions can vary widely by species (C)</p> Signup and view all the answers

<p>To detect gas production by bacteria (B)</p> Signup and view all the answers

<p>Growth on general non-specific media (D)</p> Signup and view all the answers

<p>A culture containing only cells of one single species (D)</p> Signup and view all the answers

<p>Coagulation of proteins (C)</p> Signup and view all the answers

<p>High Temperature Short Time Pasteurization (HTST) (C)</p> Signup and view all the answers

<p>Temperature above boiling water (B)</p> Signup and view all the answers

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

<p>121ºC (A)</p> Signup and view all the answers

<p>It allows milk to be stored at room temperature for several months (C)</p> Signup and view all the answers

<p>Compensation for lower temperatures (B)</p> Signup and view all the answers

<p>Synthesis of new enzymes takes place. (B)</p> Signup and view all the answers

<p>To remove microorganisms from liquids (B)</p> Signup and view all the answers

<p>Viable count using spread-plate method (C)</p> Signup and view all the answers

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

<p>Small cells are often invisible under the microscope. (A)</p> Signup and view all the answers

<p>Weighing the dried pelleted cells (D)</p> Signup and view all the answers

<p>A standard curve for each species must be prepared. (C)</p> Signup and view all the answers

<p>Cell lysis and potential death may occur. (C)</p> Signup and view all the answers

<p>Special counting chamber (C)</p> Signup and view all the answers

<p>To filter out bacteria from the air (B)</p> Signup and view all the answers

<p>They filter most bacteria. (B)</p> Signup and view all the answers

<p>The plasma membrane shrinks away from the cell wall. (D)</p> Signup and view all the answers

<p>It can cause genetic mutations in humans. (D)</p> Signup and view all the answers

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

<p>Kill or remove all forms of microbial life (B)</p> Signup and view all the answers

<p>By denaturing proteins and disrupting cell membranes (B)</p> Signup and view all the answers

<p>70% (D)</p> Signup and view all the answers

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

<p>Food may be unevenly heated and can harbor bacteria. (A)</p> Signup and view all the answers

<p>To reduce the number of pathogens on living tissue (B)</p> Signup and view all the answers

<p>Disinfectants are applied to inanimate objects, while antiseptics are applied to living tissue. (A)</p> Signup and view all the answers

<p>Mechanical removal of most microbes in a limited area (D)</p> Signup and view all the answers

<p>Color of the surface being treated (C)</p> Signup and view all the answers

<p>To reduce pathogens to acceptable public health standards (B)</p> Signup and view all the answers

<p>Presence of bacterial contamination indicating decay (B)</p> Signup and view all the answers

The time it takes for a bacterial population to double in size.

The initial period where bacterial growth is slow or non-existent. Cells adapt to new conditions.

The phase where bacterial cells divide at a constant rate.

The phase where bacterial growth stops due to resource depletion or buildup of waste products.

A method for determining the total number of bacteria, both living and dead.

A method for determining the number of living bacteria.

A method to measure bacterial growth using light scattering.

Techniques used for measuring bacterial population size.

How quickly bacteria grow and divide, influenced by factors like species and environmental conditions.

The asexual reproduction method of most prokaryotes, where one cell divides into two identical daughter cells.

Some bacteria reproduce using methods other than binary fission, creating multiple offspring cells or budding.

Changes in bacterial DNA that can lead to resistance or other new traits.

The transfer of genetic material between bacteria through processes like transformation, conjugation, and transduction.

A mutation that allows bacteria to survive and grow in the presence of an antibiotic.

A change in a single base pair (A, T, C, or G) within DNA.

Bacteria that are altered to require special nutrients to grow and thrive.

A preparation of bacterial cells on a slide for microscopic viewing.

Bacterial staining using only one dye to view cell morphology.

Staining using multiple dyes to distinguish bacteria types.

A differential staining technique to classify bacteria as Gram-positive or Gram-negative.

Staining to identify bacteria with waxy cell walls (resistant to water-based stains).

Staining bacterial endospores (resistant structures) to visualize them.

The change in microbial cell number or mass per unit time.

The time taken for a microbial population to double.

A type of media with undefined composition, used to grow various microorganisms.

Media with added ingredients, beyond basic components. Provides special nutrients for picky bacteria.

Media made from precise chemical components, with known composition, typically for specific microorganisms.

Basal media with added components like blood, serum, etc. to support the growth of fastidious organisms.

Media containing substances that change color when certain bacteria grow on them.

Substances added to media to prevent specific organisms from growing, isolating desired bacteria.

Semi-solid media used to observe the movement of bacteria

Liquid medium, usually with Peptone, meat extract, and salt, for growing microorganisms

A culture medium that differentiates lactose fermenting and non-lactose fermenting bacteria.

Media used for growing bacteria that require low oxygen levels.

A commercial envelope containing chemicals to generate anaerobic conditions.

Media that distinguishes kinds of bacteria based on their metabolic characteristics.

A culture containing only one species of microorganism.

Visual inspection of microorganisms using a microscope.

Factors impacting microbial cell growth and reproduction, including temperature, gas composition, aeration, light, and humidity.

A preparation of bacteria on a glass slide for microscopic analysis.

The time it takes for a bacterial population to double.

Initial period of slow or no bacterial growth after inoculation in new medium.

Period of rapid bacterial growth where cells double regularly.

Bacterial growth stops due to limited nutrients or waste buildup.

Method to count all cells, living and dead.

Counts only live bacteria using methods like spread-plate method.

Measure of bacterial growth based on cloudiness of a culture.

Can't distinguish between living and dead cells and hard to count small cells precisely.

Killing or removing all microbial life (including spores) from a material or object.

Heat treatment that kills Clostridium botulinum endospores in canned food.

Reducing the number of disease-causing microorganisms to a safe level.

Methods to prevent contamination during surgery and other procedures.

Removing most microbes from a specific area.

Using chemicals to clean food-handling equipment to meet health standards.

Bacterial contamination causing significant harm or tissue damage.

Number of microbes and type of microbes affect the time to eliminate a microbe population.

A method of microbial control that kills microorganisms by coagulating their proteins. It's more effective than dry heat.

A moist heat method of microbial control that heats to 100ºC or more at sea level. Kills vegetative forms, most viruses, and fungi and their spores quite quickly.

A chamber that uses hot steam under pressure to achieve sterilization with moist heat, reaching temperatures above boiling water.

A method of microbial control, developed by Louis Pasteur, that reduces microbes responsible for spoilage of beverages like milk, beer, and juices.

The ability of microbes to survive exposure to heat.

Factors impacting the effectiveness of antimicrobial methods; organic matter can hinder the effect of treatments.

Longer exposure times to chemical antimicrobials or radiation generally improve their effectiveness; this may compensate for lower temperatures in heat treatments.

A method of microbial control in which organisms are killed by oxidation.

A method of sterilization using high temperatures without moisture. It damages microbes by denaturing proteins and damaging cell structures.

Temperatures below optimal growth conditions for most microbes, slowing their metabolic processes and growth.

A method of separating microbes from a liquid or gas using a physical barrier with specific pore sizes.

Removal of water from a microbial cell, thereby inhibiting growth, survival, and reproduction.

The pressure difference between two solutions separated by a semi-permeable membrane. It affects microbial growth by causing water to move, impacting cell structure.

High-energy radiation that disrupts atoms and molecules in microbes, leading to damage and death. Gamma rays, X-rays, electron beams.

Lower energy forms of radiation, like UV light, that cause damage primarily cell components by disrupting DNA.

Solutions, like ethanol and isopropanol, that denature proteins and disrupt cell membranes of microbes; evaporating quickly and lack residual effects.