Lecture Topic 3: The Protists

A comprehensive set of flashcards covering key vocabulary and concepts from the lecture on protists.

Protists

Eukaryotic organisms that are more complex than prokaryotes and are mostly unicellular though some are colonial or multicellular.

Eukaryotes

Organisms whose cells contain a nucleus and membrane-bound organelles.

Prokaryotes

Simple, unicellular organisms that lack a nucleus and membrane-bound organelles.

Photoautotrophs

Organisms that produce their own food using light energy and contain chloroplasts.

Chemoheterotrophs

Organisms that obtain food by absorbing organic molecules or ingesting larger food particles.

Mixotrophs

Organisms that combine photosynthesis and heterotrophic nutrition.

Endosymbiotic Model

The theory that eukaryotes originated from a symbiotic relationship between different species of prokaryotes.

Cilia

Short hairlike projections used for locomotion in some protists.

Pseudopodia

Temporary extensions of a cell used for locomotion and feeding.

Flagella

Long, whip-like structures used for movement in various protists.

Excavata

A clade characterized by its unique flagellum structure, including many flagella for swimming.

Stramenopiles

A group of protists that includes diatoms, brown algae, and others, distinguishing for their cilia.

Alveolates

A clade that includes dinoflagellates and ciliates, characterized by the presence of alveoli.

Archaeplastida

A clade that includes red algae, green algae, and land plants, all of which are photosynthetic.

Unikonta

A clade that includes amoebozoans and opisthokonts (animals and fungi), known for their genetic similarities.

Amoebozoans

A group of protists characterized by flexible cell walls and movement via pseudopods.

Diatoms

A group of photosynthetic algae with silica tests, belonging to the Stramenopila clade.

Apicomplexans

Parasitic protists with complex life cycles, including the agent of malaria.

Primary Endosymbiosis

The process where a eukaryotic cell engulfs a prokaryotic cell, leading to the formation of organelles like chloroplasts.

Secondary Endosymbiosis

The process where a eukaryotic cell engulfs another eukaryotic cell, leading to additional layers of plastids.

Chloroplasts

Organelles found in photoautotrophic organisms responsible for photosynthesis.

Mitochondria

Organelles known as the powerhouses of the cell, responsible for energy production.

Symbiosis

A mutually beneficial relationship between different species.

Heterotrophic Eukaryote

Eukaryotes that obtain organic molecules from other organisms.

Nucleus

Membrane-bound organelle that contains the genetic material (DNA) of eukaryotic cells.

Genome

The complete set of genes or genetic material present in a cell or organism.

Cytoplasm

The jelly-like substance within a cell, excluding the nucleus.

Yeast

A unicellular fungus that is an example of a eukaryote.

Pathogenic Protists

Protists that cause diseases in humans or other organisms.

Food Webs

Complex interconnected feeding relationships in an ecosystem.

Euglena

A protist that can photosynthesize and has flagella for locomotion.

Trypanosoma

The genus of parasites that cause sleeping sickness.

Giardia

A pathogenic protist that causes diarrheal disease in humans.

Entamoeba

A genus of amoebozoan protists that can be pathogenic.

Evidence for Endosymbiosis

Includes the presence of DNA in mitochondrial and chloroplast organelles.