Week 3 Eukaryotes and Protists

Phagocytosis

A process of chemoheterotrophic nutrition characterized by engulfing of solid particles and intracellular digestion

Endosymbiosis

Relationship between two species where one species lives inside the other

Photosynthetic

Character of possessing the ability to fix carbon using light energy

Sessile

Characteristic of being fixed in one place

Saprophytic nutrition

Process of chemoheterotrophic nutrition characterized by the absorption of molecules digested extracellularly

Monophyletic group

Taxon that contains all the descendants of the closest common ancestor of the members of the group

Heterotrophs

Organisms that can’t fix carbon and therefore must consume organic matter for fuel

Pesudopodia

Temporary projection of eukaryotic cells usually used for movement or feeding

Supergroup

One of seven phylogenetic subdivisions of eukaryotes

Ophisthokonta

Eukaryotic supergroup that includes fungi and animals

Eukarya

All protists are part of what domain?

Giant kelp

What is the largest protist in the world?

Euglenoid

Group of freshwater flagellates; many are heterotrophic and few perform photosynthesis

Kinetoplastids

Posses a large mitochondrion with a kinetoplast; lack photosynthetic plastids

Euglena

Genus of euglenoid excavate protists that can be photosynthetic or saprophytic; can perform phagocytosis

Trypanosoma

Genus of excavate protists; includes many parasitic species

Giardia

Parasitic excavate found in feces-contaminated water

Rhodophyta

Commonly known as red algae; most members are multicellular marine macroalgae

Chlorophyta

Commonly known as green algae (but not considered a plant); has photopigments chlorophyll a and b, starch, and cellulose cell walls; some are motile

No

Does Chlorophyta display alternation of generations?

Energy storage

What does chlorophyta use starch for?

Chlamydomonas

Unicellular chlorophyta

Spirogyra

Filamentous chlorophyta

Volvox

Colonial chlorophyta

Caulerpa

Multicellular chlorophyta

Alveolata

Characerized by alveoli

Alveoli

Sac-like vesicles in alveolata; hypothesized to have played a role in ion transport and provided structural support

Dinoflagellates

Type of alveolata that possess a skeleton made of cellulose; approximately half are heterotrophic and half possess chloroplasts

Two

Dinoflagellates have how many flagella used for locomotion?

Paramecium

Single-celled and heterotrophic protists that are a type of alveolata; exhibit taxis

Cilia

Do paramecium use cilia or flagella?

Taxis

A directional behavioral response to a stimulus

Stramenopila

Extremely diverse group of protists with straw-like hairs that line surface of their flagella; Includes diatoms and kelp

Diatoms

Unicellular algae; among most abundant eukaryotes in the ocean; cell wall of silicon dioxide; contains photosynthetic pigments

carbon, oxygen

Diatoms are responsible for approximately 25% of all ____ fixation on the planet and they’re an important source of atmospheric ____

Brown algae

Multicellular seaweeds

Rhizaria

Unicellular planktonic marine algae with very narrow pseudopodia supported by microtubules

Amoebozoa

Unicellular heterotrophs in which phagocytosis and locomotion are characteristic of this group; includes slime molds

Cytoplasmic streaming

Amoebozoa are characterized by locomotion via what?

Ophisthokonta

Includes fungi, animals, and two protist groups

Choanoflagellates

Unicellular or colonial heterotrophs with choanocytes that are most closely related to animals

Choanocytes

Collared cells that act as a feeding structure in choanoflagellates

Eukaryotes

Complex single-celled and multi-celled organisms with enclosed nuclei and membrane-bound organelles

No

Are eukaryotes a monophyletic group?

Excavata

Characterized by special feeding groove and multiple membranes; some are photosynthetic and others are heterotrophic

secondary

Some excavata are photosynthetic because of ____ endosymbiosis

Stramenopila

Part of SAR clade; straw-like hairs help them swim efficiently

Alveolata

Part of SAR clade; contain sac-like vesicles that exhibit taxis

Rhizaria

Part of SAR clade; planktonic marine eukaryotes; many have axopodia

Slime molds

Ingest food particles and digest them internally

Pseudopods

“False-feet”; formed by amoebozoans which they extend around prey

Archaeplastida

Contain plastids which are photosynthetic organelles