Presentation on theme: " contain chlorophyll and carry out photosynthesis commonly called algae four phyla: euglenophytes, chrysophytes, diatoms, dinoflagellates accessory."— Presentation transcript:
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
Euglena live in water have 2 flagella for movement use chlorplasts for photosynthesis, but can turn into heterotrophs if they are kept in the dark has an eyespot used for sensing light and dark pellicle - like a cell wall, helps maintain their shapes
Cell walls made of pectin, not cellulose Food stored as oil, not starch Some are colonial
Diatoms produce thin cell walls of silicon, main component of glass Their cell walls are made of silicon; they are glasslike Used as abrasives Ex. ___________
Dinoflagellates Often have two flagella luminescent ½ are photosynthetic Biolumenescent Cause red tides
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.”
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:
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.
Pigments- all contain chlorophyll a as well as the following accessory pigments. ◦ Red- phycobilins ◦ Brown- Fucoxanthin ◦ Green- Chlorophyll a and b
Live at great depths due to pigments that need little light Most are multicellula Provide nutrients to coral reefs
All are multicellular Large and complex Mostly marine
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.