Microbiology Terms: A Quick Reference
Here’s a list of key microbiology terms and their definitions:
- Agal: A polysaccharide extracted from seaweeds.
- Growth factors: Organic compounds required for growth that an organism cannot synthesize.
- Aerobic: Organisms that use oxygen as a hydrogen acceptor.
- Anaerobic: Organisms that use a hydrogen acceptor other than oxygen and are inhibited by oxygen.
- Aerobic Types:
- Aerobic Extrista: Organisms that only use oxygen as an acceptor.
- Microaerophilic: Organisms that require only small amounts of oxygen.
- Anaerobic Facultative: Organisms that prefer the absence of oxygen but can use a different hydrogen acceptor if oxygen is present.
- Halophiles: Organisms that require high salt concentrations.
- Osmofilos: Organisms that require high osmotic pressure.
- Plasmid: Extrachromosomal genetic material found in the cytoplasm.
- Replication: The process by which a gene makes copies of itself.
- Transposon: A gene that can move from one locus (location in the DNA molecule) to another.
- Mutation: Any genetic change.
- Bacteriophages (or phage): Viruses that infect bacteria.
- Fagolitico: Producing numerous copies of itself, lysing the host bacteria.
- Prophage (Lysogenic state): Simultaneous replication of bacterial and viral DNA.
- Transformation: Direct DNA uptake by bacteria from the surrounding environment; can be natural or artificial (genetic engineering).
- Conjugation: Genetic material is physically transferred through a sex pilus.
- Transduction: Genetic material is carried and transmitted by a phage that infects prokaryotes.
- Yeast: Round or oval cells that reproduce by forming buds or blastoconidia.
- Molds (or filamentous fungi): Reproduce by spores, which may be sexual or asexual conidia.
- Dimorphic: Presenting two different forms of development under different conditions, such as temperature variations.
- Mycelium: The microscopic appearance of hyphae, which may be aerial on the surface of the culture medium or growing below the surface. Spores are found in the aerial mycelium.
- Sexual Spores:
- Ascospores: Spores located inside a cell called the ascus.
- Basidiospores: Situated on the surface of a cell called the basidium.
- Zygospores: Located in the fusion of hyphae.
- Classification of Fungi:
- Ascomycetes: Reproduce by ascospores or conidia.
- Basidiomycetes: Reproduce by conidia or basidiospores.
- Phycomycetes (or Zygomycetes): Reproduce by zygospores or conidia.
- Deuteromycetes: Reproduce only by asexual conidia.
- Viruses: Acellular infectious agents between 20 and 400 nanometers in diameter.
- Envelope: A membrane containing lipids that surrounds some viral particles.
- Virus Types:
- Icosahedral: Cubic symmetry with twenty equilateral triangle faces.
- Helical: Capsomers spiral around nucleic acid.
- Binary: A cubic head and a helical tail.
- Complex: Structures that do not fit the above definitions.
- Attachment: The interaction of a virion with a specific receptor on the cell surface.
- Penetration: Also known as viropexis, resulting in the loss of the viral coat or uncoating.
- Maturation: Viral genomes and capsid polypeptides are assembled to form progeny viruses.
- Prions: Infectious agents smaller than viruses, composed of at least one protein of 250 amino acid polypeptides and lacking nucleic acid.