Microbio_Finals__1_

Flashcards covering key vocabulary and concepts from lecture notes on microbiology, prokaryotic organisms, cell structure, microbial growth, antimicrobial control, bacterial genetics, immunology, virology, epidemiology, and eukaryotic microbes.

Spontaneous Generation

The hypothesis that living organisms can arise from non-living matter.

Biogenesis

The theory that living organisms arise from other living organisms, not spontaneously from non-living material.

Francesco Redi's Meat Experiment

Demonstrated that maggots on meat came from flies, not from spontaneous generation, using jars with and without lids.

Louis Pasteur's Swan Flask Experiment

Used a swan-neck flask to show that microbes in the air were the source of contamination, not spontaneous generation.

John Tyndall's Experiments

Confirmed Pasteur's results by showing that different types of broths required varying degrees of heat to sterilize.

Robert Hooke's Microscopic Observations

Observed cork under a microscope and coined the term cells due to the resemblance to monks' cells.

Anton van Leeuwenhoek's Observations

Discovered animalcules (microorganisms) in pond water, illustrating that microscopic life exists.

Germ Theory of Disease

Diseases are caused by microorganisms, not spontaneous factors or miasma.

Joseph Lister's Antiseptic Surgery

Used carbolic acid to disinfect surgical instruments and wounds, reducing infections.

Robert Koch's Experiments

Identified Bacillus anthracis as the cause of anthrax, establishing postulates for linking specific microbes to specific diseases.

Bacteria

Unicellular organisms.

Yeast

Can be unicellular or multicellular.

Viruses

Non-cellular entities.

Health and Disease

Microbes cause diseases; normal microbiota aids digestion and immune function.

Microbes in the Environment

Crucial for nutrient cycling, decomposition, and nitrogen fixation.

Food Production

Used in fermentation for products like bread, cheese, and yogurt.

Biodegradation and Bioremediation

Break down pollutants and clean up environmental contaminants.

Biotechnology and Genetic Engineering

Used in research and industry to create or modify products.

Research Tools

Model organisms for studying basic biological processes.

Bacteria (Domain)

Prokaryotic, no introns, cell wall with peptidoglycan.

Archaea

Prokaryotic, some introns, cell wall without peptidoglycan.

Eukarya

Eukaryotic, contains introns, membrane-bound nucleus.

Writing Bacterial Names

Always italicized, genus capitalized, species lowercase (e.g., Escherichia coli).

16S rRNA

A highly conserved gene sequence used to classify organisms into domains.

Eukaryotes

Have organelles, a nucleus, and complex cell structures.

Prokaryotes

Lack organelles, have a simpler structure, and no nucleus.

Acellular Infectious Agents

Includes viruses, viroids, and prions; non-cellular.

Taxonomy

The science of classification, involving naming, describing, and organizing organisms.

Species Definition

Defined by genetic similarity, phenotype, and reproductive isolation (in bacteria).

Phylogeny

The evolutionary history and relationships among organisms.

Phenotypic Groupings

Categorizing organisms based on observable traits (morphology, behavior, metabolism).

Genotypic Groupings

Based on genetic sequences.

Microscopic Characteristics

Shape (cocci, bacilli, spirilla), arrangement (chains, clusters), staining (Gram stain).

Metabolic Characteristics

Species exhibit unique growth patterns and metabolic traits; dichotomous keys are used for identification.

Serology

Study of antigen-antibody interactions; identifies organisms based on reaction with specific antibodies.

MALDI-TOF

Mass spectrometry technique used to identify organisms based on protein fingerprints.

Nucleic Acid Probes

Used to detect specific DNA or RNA sequences in Identification, Classification, and Categorization.

FISH (Fluorescence In Situ Hybridization)

Used to visualize specific nucleic acids in cells.

NAATS/PCR

Techniques for amplifying and detecting specific DNA sequences.

Stability of rRNA

Sequences are stable, allowing for reliable classification and phylogenetic analysis.

DNA-DNA Hybridization

Measures relatedness by determining how much two DNA strands from different organisms bind together.

Species

A group with high genetic similarity.

Strains

Subgroups with unique traits important for epidemiology and treatment.

Capsule/Slime Layer

Protects the cell from phagocytosis and desiccation.

Flagella

Used for motility.

Cell Wall

Provides structure and protection; composed of peptidoglycan.

Plasma Membrane

Regulates transport and provides structural integrity.

Ribosomes

Sites of protein synthesis.

Pili

Appendages for attachment (e.g., F-pili for conjugation).

Endospores

Resistant structures for survival in harsh conditions.

Genome Organization

Typically a single circular chromosome.

Plasmids

Small, circular DNA molecules carrying extra genes.

Plasma Membrane (Prokaryotic vs Eukaryotic)

Both have phospholipid bilayers, but eukaryotes have more complex proteins.

Cell Wall (Prokaryotic vs Eukaryotic)

Prokaryotes typically have a cell wall, while eukaryotes may or may not.

Flagella (Prokaryotic vs Eukaryotic)

Prokaryotic flagella rotate; eukaryotic flagella whip.

Ribosome Structure (Prokaryotic vs Eukaryotic)

Prokaryotes have 70S ribosomes; eukaryotes have 80S.

Organelles (Prokaryotic vs Eukaryotic)

Absent in prokaryotes, present in eukaryotes.

DNA Location (Prokaryotic vs Eukaryotic)

Prokaryotes have DNA in the nucleoid; eukaryotes in a nucleus.

Types of Transport (Prokaryotic vs Eukaryotic)

Both have passive and active transport; eukaryotes may have endocytosis.

Cell Wall Thickness (Gram-Positive vs Gram-Negative)

Gram-positive has a thicker wall; Gram-negative has a thin wall and an outer membrane.

Outer Membrane (Gram-Positive vs Gram-Negative)

Present in Gram-negative cells, not in Gram-positive.

Susceptibility to Detergents and Antibiotics (Gram-Positive vs Gram-Negative)

Gram-positive generally more susceptible to certain antibiotics, while Gram-negative has a barrier due to the outer membrane.

Main Parts of Compound Light Microscope

Ocular lens, objective lenses, stage, diaphragm, light source.

Types of Microscopes

Vary based on magnifying power (light microscopes, electron microscopes, etc.).

Concepts of Microscopy

Magnification, resolution, and contrast.

Types of Microscopes (Detailed)

Phase-contrast, fluorescence, confocal, etc.

Electron Microscopes

TEM (Transmission Electron Microscope) and SEM (Scanning Electron Microscope) have higher resolution than light microscopes.

Chemical Stains/Dyes

Acidic and basic dyes.

Classes of Staining Techniques

Simple, differential, and special/structural.

Gram Stain Method

Involves crystal violet, iodine, alcohol, and safranin to distinguish Gram-positive from Gram-negative.

Heat Fixation

Used to adhere the sample to the slide and kill the cells.

Binary Fission

Prokaryotic cell division where one cell divides into two.

Exponential Growth

A pattern of growth where the population doubles at regular intervals.

Exponential Growth Formula

Nt=N0×2n, where N0 is the initial number of cells, n is the number of generations, and Nt is the final number of cells.

Biofilms

Complex communities of microorganisms adhering to surfaces; can be beneficial or harmful.

Lag Phase

Cells adapt to new conditions.

Log/Exponential Phase

Rapid cell division; most sensitive to antibiotics.

Stationary Phase

Rate of cell division equals the rate of cell death.

Death Phase

Cell death rate exceeds cell division; logarithmic decrease in cell number.

Phase of Prolonged Decline

A few survivors continue to divide, often due to adaptations.

Effect of Temperature on Bacterial Growth

Optimal ranges differ by species.

Effect of Nutrient Availability on Bacterial Growth

Affects growth rate and phase transitions.

Effect of Oxygen on Bacterial Growth

Aerobes, anaerobes, microaerophiles, etc.

Psychrophiles

Thrive at low temperatures (e.g., arctic environments).

Mesophiles

Optimal growth at moderate temperatures (e.g., human body).

Thermophiles

Prefer higher temperatures (e.g., hot springs).

Psychotrophs

Grow at low temperatures but can also thrive at moderate temperatures.

Hyperthermophiles

Thrive at extreme temperatures (e.g., hydrothermal vents).

Obligate Aerobes

Require oxygen for growth.

Microaerophiles

Grow best in low oxygen conditions.

Obligate Anaerobes

Cannot tolerate oxygen.

Aerotolerant Anaerobes

Tolerate oxygen but don't use it.

Facultative Anaerobes

Can grow with or without oxygen.

Photoautotrophs

Use light energy and carbon dioxide for growth.

Photoheterotrophs

Use light energy but require organic carbon.

Chemolithoautotrophs

Use inorganic chemicals for energy and carbon dioxide for carbon.

Chemoorganoheterotrophs

Use organic chemicals for both energy and carbon.

Sterilization

Destruction of all microbial life, including spores and viruses.

Pasteurization

Application of mild heat to destroy pathogens and reduce spoilage organisms.

Sanitization

Reduction of microbial levels to a safe level.