The Origin and Diversification of Eukaryotes

Flashcards created from lecture notes covering key concepts of Eukaryotic origins, diversification, and their ecological impact.

Endosymbiosis

A relationship where one organism lives inside the body or cells of another organism.

Eukaryotes

Organisms whose cells have a nucleus enclosed within membranes, distinct from prokaryotes which lack a nucleus.

Multicellularity

The state of being composed of multiple cells which are specialized and dependent on each other.

Diatoms

Unicellular algae with a two-part glass-like wall, serving as primary producers in aquatic food chains.

Plasmodium

A parasitic protist responsible for malaria, using both mosquitoes and humans as alternate hosts in its life cycle.

Choanoflagellates

Single-celled or colonial protists similar to sponge collar cells, providing evidence for the close relationship to animals.

Phototroph

Organisms that make their own food using light energy, primarily through photosynthesis.

Heterotroph

Organisms that ingest or absorb organic material from other organisms for energy.

Mixotroph

Organisms that can both photosynthesize and absorb food depending on environmental conditions.

Mitochondria

Cell organelles that generate energy for the cell and are believed to have originated from aerobic alpha-proteobacteria.

Plastids

Organelles in plant cells that conduct photosynthesis, believed to have descended from photosynthetic cyanobacteria.

Colonial species

Collections of independent cells living together.

Ciliates

A group of protists that move using hair-like structures called cilia.

Red tides

Natural phenomena caused by the bloom of dinoflagellates, often resulting in toxins harmful to marine life and humans.

Giardia intestinalis

A parasitic protist that causes 'hiker's diarrhea' and spreads through contaminated water.

Trypanosoma

A genus of protists that cause diseases such as sleeping sickness and Chagas's disease.

Cytoskeleton

A network of fibers that provides structural support and facilitates cell movement.

Ediacaran period

The period in Earth's history roughly 600 million years ago when larger multicellular eukaryotes first appeared.

Amoebas

Single-celled eukaryotes that move by forming pseudopodia.

Green algae

Photosynthetic eukaryotes closely related to land plants, found in various aquatic environments.