Botany | Algae | Dr. Sara Browning | PBA Fall 2024

With flagellated zoospores

Reproductions: Asexual

zoospores

flagellated spores

Most with alternation of generations- both isomorphic and heteromorphic; others haploid or diploid

Reproduction: Sexual

isomorphic

Referring to alternating generations in plants and certain algae in which the sporophytes and gametophytes look alike, although they differ in chromosome number.

heteromorphic

Referring to a condition in the life cycle of plants and certain algae in which the sporophyte and gametophyte generations differ in morphology.

Phytoplankton

Unicellular Algae

___________- very important producers globally

Blooms

Unicellular Algae

Population explosions or "____" common

Dead zones

Unicellular Algae

Some blooms may be toxic or cause "_____ _____" due to eutrophication

Dead zones

In a body of water, an area with extremely low oxygen concentration and very little life

Eutrophication

A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria.

Coccolithophores

microscopic algae with calcium carbonate shells, form the base of many marine food webs

Diatoms

A unicellular photosynthetic alga with a unique glassy cell wall containing silica

Dinoflagellates

plant-like protist that causes red tide

Bacillariophyceae

Diatoms- Class ___________

(old Phylum Chrysophyta)

* Stramenopile supergroup

Silicious (SiO2)

Diatom Characteristics

Cell wall:

Fucoxanthin, Chl c

Diatom Characteristics

Color:

Motile by secretion

Diatom Characteristics

Mobility:

Salt Water (SW), Fresh Water (FW), terrestrial

Diatom Characteristics

Environment:

Very abundant phytoplankton at all surface of the world's oceans

Diatom Ecology

Undefined

Dinoflagellates

(old Phylum Pyrrophyta)

* Alveolata supergroup

Biflagellates

Dinoflagellate Characteristics

-

Naked (no cell wall) or Armored (cellulose plates)

Dinoflagellate Characteristics

Cell wall:

Peridinin (Carotenoid); Chl c

Dinoflagellate Characteristics

Color:

Very abundant phytoplankton at the surface of the world's oceans

Dinoflagellate Ecology

1) Red Tide

2) Shellfish Poisoning

3) Bioluminescence

4) Zooxanthellae

Four Special Features of Dinoflagellates

1)

2)

3)

4)

Red Tide

An algal bloom that occurs in salt water

Karenia brevis

dinoflagellate that causes red tide

Bioluminescence

the production of light by means of a chemical reaction in an organism

Noctiluca

microscopic marine animals that make the ocean glow during the night

Zooxanthellae

a yellowish-brown symbiotic dinoflagellate present in large numbers in the cytoplasm of many marine invertebrates.

Seaweeds and Pondweeds

Multicellular Algae

-

-

Seaweed blade

Seaweed Stipe

Seaweed holdfast

Phaeophyceae

Brown Algae

Class __________

* Stramenopile supergroup

Marine seaweeds

Brown Algae Characteristics

Environment:

Fucoxanthin; Chl c

Brown Algae Characteristics

Color:

Common in cold and temperate Salt water

Kelp "Forest"

Brown Algae Ecology

Sargassum

- Sargassum or Gulfweed scientific name

Tubinaria

Rhodophyta

Red Algae

Phylum ________

* Plants and algal relatives supergroup

Marine Seaweeds

Red Algae Characteristics

Environment:

Phycobilins- Phycoerythrin and phycocyanin; Chl d

Red Algae Characteristics

Color:

Common in tropical and warm Salt Water

Deepest seaweed ~ 970 ft

Many are calcareous and coralline

Red Algae Ecology

Calcareous

containing calcium carbonate

Coralline

resemble corals

Undefined

Green Algae

(old Phylum Chlorophyta)

* Plants and algal relatives supergroup

Unicellular, colonial, filamentous, coenocytic, flat sheets of cells, parenchyma-like tissue

Green Algae Characteristics

Diverse body plans:

Unicellular green algae

Chlamydomonas

Colonial green algae

volvox and spirogyra

Filamentous green algae

spirogyra and cladophora

Coenocytic green algae

Cell grows and the nucleus divides, but the cell does not divide, resulting in a large, multinucleated cell

Flat sheets of cells green algae

Parenchyma-like tissue green algae

Chl b; beta carotene

Green Algae Characteristics

Color:

Store starch

Green Algae Characteristics

Storage:

Plant-like chloroplasts

Green Algae Characteristics

Chloroplasts:

Plant

Green Algae Characteristics

One group probably sister group to ______ Kingdom

Common in FW

Common in shallow, tropical SW

Calcareous species common

Green Algae Ecology

Mermaids hair

Caulerpa

Caulerpa scientific name

Halimeda

Halimeda scientific name

Nori (red); Wakame (kelp); Kombu (kelp)

Commercial Importance

Food:

Thickeners and stabilizers from kelp and other brown algae

Commercial Importance

Alginates:

Growth medium for microorganisms from red algae

Commercial Importance

Agars:

Emulsifiers from red algae

Commercial Importance

Carrageenans