Microbiology Terms

Microbiology Basics

• Acid-fast bacteria (AFB) maintain their color after acid treatment, e.g., tuberculosis and leprosy.
• Acid-fast stain, such as Ziehl-Neelsen stain, is used to identify AFB.

Microbiology Terminology

• Aerosol: a spray of fine particles in the air.
• Agar: an extract of seaweed used to grow bacteria.
• Agar plate: a sterile petri dish with solidified agar.
• Agar slant: a tube with solidified agar at an angle.
• Anaerobe: an organism that grows without oxygen.

Bacteria and Microorganisms

• Bacillus: rod-shaped bacteria.
• Bacteria: one-celled microorganisms.
• Bacteriology: the study of bacteria.
• Chlamydia: tiny, intracellular parasites causing sexually transmitted diseases.

Microbiology Techniques

• Aseptic technique: a routine to prevent contamination and maintain sterility.
• Culture: the act of growing bacteria on media.
• Culture and Sensitivity (C&S): growing a microorganism and testing for effective antibiotics.
• Gram's stain: a method to differentiate between Gram-positive and Gram-negative bacteria.
• Inoculation: introducing microorganisms to media using an inoculation loop.

Microbiology Terms

• Cocci: spherical-shaped bacteria.
• Colony: a mass of bacteria growing on media.
• Medical Microbiology: the study of living microorganisms causing human infections and diseases.
• Media: a solid or liquid substance containing nutrients for growing bacteria.
• Mordant: a substance that helps dye stick to an object, e.g., iodine.
• Mycology: the study of fungi.
• Normal Flora: bacteria normally found in the body, e.g., staph on skin, E. coli in the colon.
• Parasite: an organism that lives off another living creature, e.g., tape worm.
• Parasitology: the study of parasites.

Microbiology Concepts

• Pathogens: disease-causing microorganisms.
• Petri Dish: a flat, plastic plate with a cover holding media.
• Septicemia: the presence of microorganisms in the blood.
• Spirilla: spiral-shaped microorganisms.
• Sputum: mucous secretions from the lungs.
• Transport media: used to transport microorganisms to the lab for culture, keeping them alive.

Microbiology Studies

• Bacteria, fungi, parasites, rickettsiae, and viruses are studied in microbiology.
• Rickettsiae: tiny bacteria resembling both bacteria and viruses, requiring a host cell to survive, e.g., typhus, Rocky Mountain Spotted Fever.

Microbiology Laboratory

• Microbiology department: identifies organisms causing illnesses in the lab.
• Nosocomial infection: an infection spread in a healthcare facility, also called Healthcare-associated infection (HAI).
• Patient instructions for C&S: include expiration date, patient information, and collection procedures.

Microbiology Media

• Media consists of amino acids, sugars, minerals, salts, and vitamins, and may contain cooked blood, meat, milk, etc.
• Media types:
  • Supportive/basal media: provides minimum requirements for growth, e.g., Mueller Hinton (MH).
  • Enrichment media: inhibits normal flora growth and enhances pathogen growth, e.g., chocolate agar, blood agar.
  • Selective media: inhibits some organism growth while enhancing others, e.g., Salmonella-Shigella (SS), Mannitol salt agar for staph aureus.
  • Differential media: has indicators that some bacteria use, e.g., MacConkey's.