Microbiology midterm

Microbiology midterm

Nucleotide

The monomer of DNA and RNA, consisting of a phosphate group, sugar, and nitrogenous base.

Polynucleotide

The polymer form of nucleotides, forming DNA or RNA.

Monosaccharides

Simple sugars, the monomers of carbohydrates, e.g., glucose.

Polypeptide

The polymer of amino acids that forms proteins.

Phospholipids

Lipids with a hydrophilic head and hydrophobic tails, major components of cell membranes.

Hydrophobic

A property of molecules that repel water.

Hydrophilic

A property of molecules that attract water.

Amino Acids

Organic compounds that serve as the monomers of proteins.

Carboxyl Group

(-COOH) A functional group present in amino acids and fatty acids.

DNA Helix

The structure formed by the two strands of DNA winding around each other.

Gram-positive

Bacteria that retain the crystal violet stain used in the Gram staining procedure, appearing purple.

Gram-negative

Bacteria that do not retain the crystal violet stain and appear pink after Gram staining.

Acid-Fast Stain

A staining technique used primarily for Mycobacterium species that resist decolorization.

Simple Diffusion

The movement of molecules from an area of higher concentration to an area of lower concentration.

Active Transport

The movement of substances across a cell membrane against their concentration gradient, requiring energy.

Hypotonic

A solution with a lower concentration of solutes compared to another, causing cell swelling.

Endospores

Dormant structures formed by some bacteria for survival in harsh conditions.

Glycocalyx

A sticky outer layer of polysaccharides and proteins for protection and attachment.

Photoautotroph

Organisms that obtain energy from light and carbon from CO2.

Aerobic Respiration

A metabolic process that uses glucose and oxygen to produce carbon dioxide, water, and ATP.

Fermentation

An anaerobic process to generate energy from glucose, producing substances like lactic acid or ethanol.

Electron Transport Chain

A series of redox reactions that produce ATP through oxidative phosphorylation.

Facultative Anaerobes

Organisms that can grow with or without oxygen.

Psychrophile

Microorganisms that thrive at extremely low temperatures (below 20°C).

Bacteriostatic

Agents that inhibit the growth of bacteria.

Germicide

A substance that kills harmful microorganisms.

Disinfectant

A chemical agent applied to inanimate objects to reduce or eliminate microbial agents.

Aseptic Technique

Methods used to prevent contamination by unwanted microorganisms.

Autoclave

A device that uses steam and pressure for sterilization.

Lyophilization

A preservation technique involving freeze-drying.

Transduction

The process of transferring genetic material from one bacterium to another via bacteriophage.

Transformation

The uptake of free DNA from the environment by a bacterial cell.

Conjugation

The transfer of genetic material between bacteria through direct contact, often via a pilus.

PCR (Polymerase Chain Reaction)

A method used to amplify specific DNA sequences.

Gene Production

The process of inserting a gene into a vector to be expressed in host cells.

DNA Fingerprinting

A technique used to identify genetic differences among individuals.

Endosymbiosis

The theory that mitochondria and chloroplasts originated from free-living bacteria.

Antibiotic Resistance

The ability of bacteria to resist the effects of antibiotics due to various factors.

Chemoheterotroph

Organisms that obtain energy and carbon from organic compounds.

Phase-Contrast Microscope

A type of microscope that enhances contrast in unstained cells, ideal for observing live specimens.

Stereoscopic Vision

The ability to perceive depth and three-dimensional structure.

Osmosis

The diffusion of water across a selectively permeable membrane.

Gene Transfer Mechanisms

Methods by which bacteria can exchange genetic material.

Ionizing Radiation

Radiation used in sterilization that disrupts DNA.

Nonionizing Radiation

Type of radiation, such as UV light, that causes damage to DNA.

Fluorescence Microscope

A microscope that uses fluorescence to generate an image.