Rhodophyta, Chlorophyta, and Slime Molds — Vocabulary Flashcards

Vocabulary flashcards covering key terms from Rhodophyta, Green Algae (Chlorophyta and Charophyta), and slime molds.

Rhodophyta

Red algae; a division with about 6,000 species and 500–600 genera; abundant in warm marine waters, few species in freshwater.

Phycobilins

Light-harvesting pigments in red algae, aiding absorption of light for photosynthesis.

Phycoerythrin

A red phycobilin pigment that masks the color of chlorophyll a and helps absorb green/blue-green light.

Floridean starch

Major carbohydrate storage product in red algae, stored as granules in the cytoplasm.

Agar

Gel-like polymer of galactose (sulfated) in red algae; forms the gel-like layer and contributes to texture.

Coralline algae

Group of red algae with cell walls calcified by calcium carbonate; tough and stony.

Calcium carbonate cell walls

Mineralized walls in coralline red algae that aid fossil preservation.

Carposporophyte

Diploid stage in red algae that grows on the female gametophyte and bears carpospores.

Carpospores

Diploid spores produced by the carposporophyte in red algae.

Tetrasporophyte

Diploid generation that produces haploid tetraspores by meiosis.

Tetrasporangia

Structures producing tetraspores in red algae.

Spermatangia

Male reproductive structures in red algae that produce spermatia.

Spermatia

Nonmotile male gametes produced by spermatangia.

Carpogonium

Female gamete (carpogonium) in red algae; bottle-shaped with a neck called a trichogyne.

Trichogyne

Neck of the carpogonium that receives spermatia.

Monospores

Asexual spores produced by red algae.

Gametophyte

Haploid generation that produces gametes.

Sporophyte

Diploid generation that produces spores.

Diploid (2n)

Having two sets of chromosomes.

Haploid (n)

Having one set of chromosomes.

Chlorophyta

Green algae; large division including many freshwater and some marine species.

Chlorophyll a and b

Photosynthetic pigments characteristic of green algae and land plants.

Chloroplasts

Organelles where photosynthesis occurs.

Cell walls (green algae)

Mostly cellulose-based walls in most green algae.

Monophyletic

Green algae and land plants form a single, shared evolutionary lineage.

Charophyceans

Green algae group closely related to land plants; includes several key lineages.

Chlorophyceae

A major class within the green algae (Chlorophyta).

Ulvophyceae

A class of green algae, commonly including mostly coastal and marine forms.

Trebouxiophyceae

A class of green algae.

Chlorodendrophyceae

A class of green algae.

Prasinophytes

Early-diverging green algae, often small and flagellated.

Pedinophyceae

A class of green algae.

Mamiellophyceae

A class of small green algae, including Micromonas and Ostreococcus lineages.

Pyramimonadales

An order of green algae.

Pycnococcaceae

A family within green algae.

Nephroselidiophyceae

A class of primitive green algae.

Prasinococcales

An order of green algae.

Palmophyllales

An order of primitive green algae.

Streptophyta

Clade including land plants and some green algae; contrasted with Chlorophyta.

Phragmoplast

Cell division structure in land plants and some green algae; spindle forms a cell plate.

Phycoplast

Alternative cytokinesis mechanism in some green algae separate from the phragmoplast.

Charophyceans vs Chlorophyceans

Two major lineages of green algae; Charophyceans are more closely related to land plants and show key plant features.

Coleochaetophyceae

Class of green algae; closely related to land plants; contains plasmodesmata.

Zygnematophyceae

Class of green algae including desmids and related groups.

Chara (stoneworts)

Stoneworts; among the closest relatives to bryophytes; calcified walls and apical growth.

Oogonia

Egg-producing structures in Charophycean algae.

Antheridia

Sperm-producing structures in Charophycean algae.

Desmids

Unicellular green algae with two semicells separated by an isthmus.

Desmids structure (semicells and isthmus)

Two halves of a desmid cell connected by an isthmus.

Chlamydomonas

Motile, unicellular green alga with two flagella and a red eyespot.

Volvox

Colonial, motile green alga; hollow sphere of many cells; reproduction may be sexual or asexual.

Hydrodictyon

Water net; colonial green alga forming large hollow nets of connected cells.

Spirogyra

Filamentous, unbranched green alga with spiral chloroplasts; reproduces via conjugation.

Papillae

Domed bumps on Spirogyra cells that form a conjugation tube during reproduction.

Conjugation

Sexual exchange process in Spirogyra where cells form a tube and fuse to transfer protoplasm.

Cladophora

Filamentous, branched green alga; often forms mats; sporic life cycle with isomorphic generations.

Ulva

Multicellular green alga (sea lettuce); thallus up to 1 m; anisogamous and sporic life cycle.

Anisogamy

A form of sexual reproduction with unequal gamete sizes (distinct male and female gametes).

Codium

Siphonous green alga; spongy mass of densely interwoven coenocytic filaments.

Acetabularia

Mermaid's wine glass; large siphonous green alga with distinctive cap-like structure.

Ventricaria

Goes beyond a single cell; appears unicellular but is a large multinucleate mass.

Siphonous

Coenocytic organization with a continuous cytoplasm and many nuclei within a common mass.

Chlorophyta life cycles (sporic/meiosis)

Green algae display diverse life cycles; many have alternation of generations (sporic life cycle).

Slime Molds

Heterotrophic organisms once considered fungi; two groups: plasmodial Myxomycota and cellular Dictyosteliomycota.

Myxomycota

Plasmodial slime molds; lack cell walls; plasmodium is a multinucleate, streaming mass.

Dictyosteliomycota

Cellular slime molds; amoeboid cells aggregate into a pseudoplasmodium (slug) and form stalked spores.

Plasmodium

Multinucleate, streaming mass of cytoplasm in plasmodial slime molds.

Sclerotium

Encysted resting stage during drought in plasmodial slime molds.

Sporangium

Structure where spores are produced; located at tip of stalks in slime molds.

Pseudoplasmodium

Slug-like mass formed by Dictyosteliomycota during aggregation.

Myxamoebas

Feeding, amoeboid cells in cellular slime molds.