microbio ch 1 Important Terms & Definitions

Microorganism (Microbe)

A microscopic form of life including bacteria, archaea, fungi, protozoa, algae, and viruses.

Microbiology

The scientific study of microorganisms.

Cytoplasmic Membrane

A semi-permeable barrier that separates the cell’s interior from the external environment.

Cytoplasm

The gel-like substance inside the cell containing macromolecules, ions, and ribosomes.

Ribosome

A cellular structure that synthesizes proteins by translating mRNA.

Cell Wall

A rigid layer outside the cytoplasmic membrane providing structural support.

Genome

The complete set of genetic material (DNA) in a cell.

Gene

A segment of DNA that codes for a functional product (protein or RNA).

Prokaryote

A cell lacking a membrane-bound nucleus and organelles (Bacteria and Archaea).

Eukaryote

A cell containing a membrane-bound nucleus and organelles (Eukarya).

Colony

A visible mass of microorganisms originating from a single cell, grown on solid media.

Metabolism

The sum of all chemical reactions in a cell, including catabolism and anabolism.

Catabolism

Metabolic pathways that break down molecules to release energy.

Anabolism

Metabolic pathways that build complex molecules from simpler ones.

Transcription

The process of copying DNA into RNA.

Translation

The process of synthesizing proteins from mRNA at the ribosome.

Horizontal Gene Transfer

The movement of genetic material between unrelated cells (not by reproduction).

Evolution

Change in gene frequency in a population over time, leading to descent with modification.

Pathogen

A microorganism that causes disease.

Differentiation

The process by which a cell changes form or function to become specialized.