Classifications and Microbial Growth

VOCABULARY flashcards covering key concepts from the lecture notes on classification and microbial growth.

Animalia

Kingdom of multicellular, usually mobile animals that ingest food.

Plantae

Kingdom of plants; mostly photosynthetic, autotrophic, multicellular.

Fungi

Kingdom of fungi; decomposers; absorptive heterotrophs that do not photosynthesize.

Protista

Kingdom for mostly single‑celled organisms that don’t fit neatly into plants, animals, or fungi; historically a catch‑all group.

Monera

Traditional kingdom for prokaryotes (bacteria); now largely split into Bacteria and Archaea.

Taxonomy

Science of naming and classifying organisms based on shared traits.

Phylogenetics

Study of evolutionary relationships inferred from genetic material.

DNA

Deoxyribonucleic acid; the genetic material that carries hereditary information.

Ribosome

Ribosome; small RNA‑protein particle where proteins are made.

Plasma membrane

Phospholipid bilayer surrounding a cell, regulating movement of substances.

Cell

Basic unit of life; all organisms are composed of cells.

Robert Hooke

Scientist who coined the term ‘cell’ from cork observations.

Matthias Schleiden

Concluded that all plants are made of cells.

Theodor Schwann

Concluded that all animals are made of cells.

Rudolf Virchow

Proposed that all cells arise from pre‑existing cells; contributed to cell theory.

LUCA

Last Universal Common Ancestor of all current life.

Prokaryotic

Cell type lacking a true nucleus; includes bacteria and archaea.

Eukaryotic

Cell type with a true nucleus and membrane‑bound organelles.

Domain

Highest current taxonomic level; divides life into Bacteria, Archaea, and Eukarya.

Domain Bacteria

Domain of prokaryotes with peptidoglycan in cell walls; no membrane‑bound nucleus.

Domain Archaea

Domain of prokaryotes with unique lipids; many extremophiles; more related to eukaryotes.

Domain Eukarya

Domain of organisms with true nuclei and organelles (plants, animals, fungi, protists).

Peptidoglycan

Rigid polymer in most bacterial cell walls.

Nucleus

Membrane‑bound organelle in eukaryotes containing most DNA.

Nucleoid

Region in prokaryotes where DNA resides; not membrane‑bound.

Bacteria

Domain Bacteria; prokaryotes with diverse metabolisms.

Archaea

Domain Archaea; prokaryotes with distinct biochemistry; often extremophiles.

Eukarya

Domain Eukarya; organisms with nuclei and membrane‑bound organelles.

Photosynthesis

Process of converting light energy into chemical energy.

Autotroph

Organism that makes its own food from inorganic sources.

Heterotroph

Organism that relies on organic compounds produced by others.

Selective media

Culture media that suppress some microbes to allow others to grow.

Differential media

Media that reveal differences between microbes via visible changes.

Biochemical test

Lab tests to determine metabolic capabilities of a microbe.

Binomial nomenclature

System of naming species using two terms: genus and species epithet.

Genus

First part of a binomial name; capitalized.

Species

Second part of a binomial name; lowercase.

Staphylococcus aureus

Bacteria forming grape‑like clusters; colonies often golden.

Escherichia coli

Common model bacterium; example of binomial nomenclature.

Arbutus unedo

Binomial name for the strawberry tree; example of Linnaeus’ naming.

Growth curve

Graph showing the number of bacteria over time with four phases.

Lag phase

Phase with little to no division as cells adapt.

Log phase

Exponential growth phase; rapid cell division.

Stationary phase

Phase where growth ceases due to nutrient depletion and waste buildup.

Death phase

Phase where cell death exceeds formation due to adverse conditions.

Plate count

Counting colonies on plates to estimate viable cell numbers.

Hemocytometer

Counting chamber for cells under a microscope.

Simple dilutions

Process of diluting a sample with a diluent to reduce concentration.

Dilution factor

Ratio describing dilution level; e.g., 1/10 or 1:10.