Lecture 1 Vocab

Algae

Photosynthetic eukaryotic organisms (can be unicellular or multicellular) that produce oxygen and serve as the base of aquatic food chains.

Archaea

Prokaryotic microorganisms distinct from bacteria; often found in extreme environments; lack peptidoglycan in their cell walls.

Bacteria

Single-celled prokaryotic organisms with peptidoglycan cell walls; diverse metabolisms; some pathogenic, many beneficial.

Bacteriophage

A virus that infects and replicates inside bacteria; used in phage therapy and molecular biology research.

Biogenesis

The principle that living organisms arise only from pre-existing living organisms, not from nonliving matter.

Cytoskeleton

A network of protein filaments in eukaryotic cells that provides structural support, shape, and aids in intracellular transport.

Endomembrane system

A system of interconnected, membrane-bound organelles in eukaryotes, including ER, Golgi, lysosomes, and vesicles.

Endospore

A highly resistant, dormant bacterial cell structure that allows survival in harsh conditions.

Endospore coat

The protective protein layer surrounding the endospore; provides resistance to chemicals and enzymes.

Endospore cortex

A thick peptidoglycan layer beneath the coat; helps maintain dehydration and heat resistance.

Endospore core

The innermost region of an endospore containing DNA, ribosomes, enzymes, and dipicolinic acid for stability.

Eukarya

One of the three domains of life; organisms with membrane-bound nuclei and organelles.

Kingdom-specific infection

A pathogen or virus that only infects organisms within a single biological kingdom.

Membrane-bound organelle

Structures in eukaryotic cells surrounded by membranes (e.g., nucleus, mitochondria, ER).

Pasteurization

A heat process developed by Louis Pasteur to kill pathogens in food and beverages, without affecting quality.

Peptidoglycan

A polymer of sugars and amino acids that forms a mesh-like cell wall unique to most bacteria.

Prion

A misfolded protein capable of causing neurodegenerative diseases by inducing other proteins to misfold.

Prokarya

The domain of life that includes Bacteria and Archaea; organisms without nuclei or membrane-bound organelles.

Protozoa

Unicellular eukaryotes that are often motile and heterotrophic; some are parasitic.

Spontaneous generation

The disproven idea that life can arise from nonliving matter.

Viroid

A small, circular RNA molecule without a protein coat that infects plants and disrupts growth.

Virus

An acellular infectious particle composed of nucleic acid and protein; requires a host cell to replicate.

Ferdinand Cohn

German botanist who classified bacteria and discovered endospores.

Robert Hooke

First to publish drawings of microorganisms using a microscope; coined the term "cell."

Louis Joblot

Performed experiments that provided evidence against spontaneous generation.

John Needham

Conducted flawed experiments that seemed to support spontaneous generation.

Louis Pasteur

Demonstrated that microorganisms cause fermentation and disease; disproved spontaneous generation with swan-neck flask experiment; developed pasteurization and vaccines.

Antonie van Leeuwenhoek

First to observe and describe living microorganisms using a simple microscope; called them "animalcules."

John Tyndall

Demonstrated that dust carries microorganisms and showed that prolonged heating could destroy heat-resistant endospores.