Classification of Protists Flashcards

Study Notes

Supergroups of Protists

Archaeplastida: Includes red algae, green algae, and land plants; originated from an endosymbiotic relationship between heterotrophic protists and cyanobacteria.
Amoebozoa: Comprises eukaryotes with amoeba-like cells characterized by movement and feeding through pseudopodia.
Chromalveolata: Proposed supergroup containing alveolates and stramenopiles, likely arising from secondary endosymbiosis; notable for membrane-enclosed sacs (alveoli).
Excavata: Contains flagellated, asymmetrical organisms with a distinct feeding groove; includes diplomonads and euglenozoans.
Opisthokonta: Monophyletic group encompassing choanoflagellates, fungi, and animals; features a single apical flagellum with a contractile collar.
Rhizaria: Notable for foraminifera with porous shells housing harbored photosynthetic algae; includes radiolarians with intricate glassy silica exteriors.

Key Features and Examples

Pseudopodia: Cellular extensions used for movement and feeding in amoeboid cells.
Flagella: Whiplike structures aiding movement in single-celled organisms.
Cilia: Hairlike projections enhancing locomotion, different from flagella.
Alteration of Generations: Protists undergo complex sexual life cycles alternating between diploid and haploid phases.

Specific Organisms and Functions

Diplomonads (Excavata): Possess mitosomes, two identical nuclei, and multiple flagella.
Euglenozoans (Excavata): Utilize two long flagella for movement; contain an eyespot for light sensing.
Giardia lamblia: Waterborne protist causing severe diarrhea.
Trypanosoma brucei: Kinetoplastid responsible for African sleeping sickness.
Green Algae (Archaeplastida): Share chloroplast features with land plants; two main types are chlorophytes and charophytes.
Red Algae (Archaeplastida): Primarily multicellular, lack flagella, vary in size and complexity.
Stramenopiles (Chromalveolata): Include diatoms and brown algae; characterized by textured flagella.
Slime Molds (Amoebozoa): Categorized into plasmodial and cellular based on their life cycles.

Functional Roles in the Environment

Foraminifera utilize pseudopodia for trapping and engulfing food.
Radiolarians employ needle-like pseudopods for capturing food particles.
Green algae and red algae contribute to aquatic ecosystems and serve as primary producers.

Description

Explore the fascinating world of protists with these flashcards! This quiz covers the classification of various supergroups such as Archaeplastida, Amoebozoa, and Chromalveolata, along with their unique characteristics. Perfect for students studying biology!