Plantlike Protists

contain chlorophyll and carry out photosynthesis

commonly called algae four phyla: euglenophytes, chrysophytes, diatoms, dinoflagellates

accessory pigments help absorb light, give algae a variety of colors

General characteristics

Euglena live in water

have 2 flagella for movementuse chlorplasts for photosynthesis, but can turn into heterotrophs if they are kept in the darkhas an eyespot used for sensing light and darkpellicle - like a cell wall, helps maintain their shapes

Phylum Euglenophyta

Euglena algal bloom

Chrysophytesyellow-green algae, "golden plants"

Cell walls made of pectin, not cellulose

Food stored as oil, not starch

Some are colonial

Diatomsproduce thin cell walls of silicon, main component of glass

Their cell walls are made of silicon; they are glasslike

Used as abrasivesEx. ___________

Phylum Bacillariophyta

DinoflagellatesOften have two flagellaluminescent

½ are photosyntheticBiolumenescentCause red tides

Phylum Pyrrophyta

Red Tide is caused by a "population explosion" of toxic, naturally occurring microscopic plankton (specifically, a subgroup known as dinoflagellates). "Blooms" of the poison-producing plankton are coastal phenomena caused by environmental conditions, which promote explosive growth. Factors that are especially favorable include warm surface temperatures, high nutrient content, low salinity, and calm seas. Rain followed by sunny weather in the summer months is often associated with red tide blooms.

Alexandrium fundyense, along the Atlantic Northeast coast, ranging from the Canadian Maritimes to Southern New England;

Alexandrium catenella, on the Pacific West Coast from California to Alaska; and

Karonia brevis, in the Gulf of Mexico along the West Florida coast.

Does it really color the water?Yes, water in coastal areas can be colored red by the algae, thus the term "red tide.”

Penn Cove, Washington

Red tide algae make potent natural toxins. It is unknown why these toxins are created, but some can be hazardous to larger organisms throught the processes of biomagnification and bioaccumulation. Grazers such as fish and krill are unaffected by the toxins, so as they eat the algae the toxins are concentrated and accumulate to a level that is poisonous eat to organisms that feed on them. Large fish kills and several mammalian diseases and deaths have been attributed to consumption of shellfish during red tide algal blooms. Diseases that may affect humans include:

How harmful are algal blooms?

Paralytic Shellfish Poisoning (PSP )- PSP toxins disrupt nerve function and cause paralysis. Extreme cases may result in death by asphyxiation by respiratory paralysis. It usually comes from shellfisht.

Red Tides

Pigments- all contain chlorophyll a as well as the following accessory pigments.◦Red- phycobilins◦Brown- Fucoxanthin◦Green- Chlorophyll a and b

Algae Protists

Live at great depths due to pigments that need little light

Most are multicellulaProvide nutrients to coral reefs

Red algae

All are multicellularLarge and complexMostly marine

Brown algae

The Sargasso Sea 1100 km x 750 km

Image from space

Green algae

Ancestors of green plants No fossils Some are single-celled; some colonial; some multicellular

Many multicellular are filamentous, such as spirogyra

Reproduction is similar to mosses by Alternation of Generations.

Switching back and forth between haploid (n) gametophyte, which makes gametes (sex cells) and diploid (2n) sporophyte, which makes spores.

Unusual in that the gametophyte is actually an organism that is visible and can live on its own.

Alternation of generations

Alternation of Generations

Write down 3 human uses of algae and 1 non-human.

Human Uses of Algae

Slime molds-important decomposers◦Phylum AcrasiomycotaCellular slime molds-. They are amoeboid and make fruiting bodies.

Funguslike Protists

Acellular slime molds

Phylum Myxomcota- they also start out amoeboid but then aggregate to form plasmodia.

They can grow to be several meters long.

Use your book to research this.

Ecology of Funguslike Protists

DecomposersPlant diseases including some major blights.

P. infestans may be responsible for many of you being in the U.S. Explain this and then discuss it with your neighbor.

Ecology