Primary Producers

Photosynthesis vs. Respiration Photosynthesis – Occurs in chloroplasts – Solar energy captured by chlorophyll – Oxygen by-product Sunlight + CO 2 + H 2 O ----> O 2 + Sugars Respiration – Occurs in mitochondria – Release of energy from breaking down sugars – Carried out by both autotrophs and heterotrophs Sugars + O > CO 2 + H 2 O + chemical energy

Phytoplankton Phyto (plant) planktos (wandering) Microscopic plants that live in the ocean Over 10,000 species of phytoplankton Foundation of the marine food chain 2/3 of all the photosynthesis that takes place is in the oceans

Phytoplankton Cyanobacteria Diatoms Dinoflagellates Protozoa Algae Flowering Plants Sea grasses Mangroves

Cyanobacteria Blue-green bacteria Cyanobacteria can be found in almost every terrestrial and aquatic habitat: in oceans, fresh water – even bare rock and soil.

Diatoms Marine producers Are unicellular Enclosed by cell walls made largely of silica Aggregate into chains or star-like groups

Dinoflagellates Have a flagella to swim A bit larger than diatoms Some are bioluminescent- ability to emit light (glow) 90% live of dinoflagellates live in the ocean

Protozoa Animal-like protists Have chloroplasts Autotrophic & Heterotrophic Ex. Euglena, Volvox

Algae Simple aquatic organisms Eukaryotic Photosynthetic

Popular name- seaweed Multicellular Eukaryotic Lots of variation in structure and appearance Three types of seaweed – Green algae – Brown algae – Red algae

Marine Flowering Plants Kingdom Plantae Angiosperms: aka flowering plants Dominant land plants Few species live in marine environments Have true roots, stems, and leaves All have flower as dominant reproductive organ

Seagrasses Resemble grasses, but are not grasses at all Pollen for reproduction is carried by water currents Eelgrass – species – Found in shallow coastal waters – Have ribbon-like leaves – Common in oxygen poor sediments

Turtlegrass Eelgrass

Salt-Marsh Plants Cordgrasses – Live on land, but are salt tolerant – Not completely submerged – Become submerged during high tidal periods

Mangroves Trees and shrubs living on tropical shores Land plants that tolerate salt Grow in mud bottom estuaries, and coastal lagoons Arched roots trap sediment and cause more land to build up expanding the colony toward the sea

Red Mangrove

Seaweed

General Structure No true leaves, stems, or roots Thallus- Body structure Blades- leaf like structure – Main photosynthetic regions Pneumatocysts – Gas filled bladders which help keep blades near sea surface maximizing exposure to sun Stipe – Stem-like structure which provides support Holdfast – Root-like structure which attaches thallus to the bottom Do not penetrate through the sand or mud Do not play a significant role in absorption of water and nutrients

Macroalgae Structure

Chlorophyta- Green algae Occur in both Freshwater and Marine environments Bright green in color because chlorophyll is not masked by other pigments Ulva- Sea lettuce Codium fragile- Dead man’s fingers Over 8,000 species 90% are freshwater / 10% saltwater

Ulva Lactuca Kingdom: Protista Phylum: Chlorophyta Class: Ulvophyceae Order: Ulvales Family: Ulvaceae Genus: Ulva Species: Lactuca Genus Ulva- Sea Lettuce

Codium fragile- Dead man’s fingers Kingdom: Protista Division: Chlorophyta Class: Bryopsidophyceae Order: Codiales Family: Codiaceae Genus: Codium species: fragile

Phaeophyta- Brown Algae 1500 species Predominantly marine Range in color from olive to dark Common in rocky shores Brown due to yellow-brown pigments – Fucoxanthin Pigment in brown algae that dominates over chlorophyll

Phaeophyta Rockweeds and Kelps Kelp forests play an important role in marine ecology by providing food and shelter for marine organisms Some species grow very large – Nereocystis- Bull Kelp’s stipe can be up to 30 meters long – Macrocystis- Stipes can be up to 100 meters long These giant kelp are estimated to grow 50cm per day!!!!

Phaeophyta Kelp Forest Temperate Rain Forest

Rhodophyta: Red Algae More species than of other two types – 4,000 species – Only a few fresh water species Red pigments: phycobilins – These pigments mask chlorophyll Common in rocky shorelines Coralline Algae – These species deposit calcium carbonate within their cell walls – Are actively involved in the formation of coral reefs

Rhodophyta

Reproduction In Algae Asexual reproduction is common – Vegetative reproduction – Fragments of thallus can grow into new organisms – Some reproduce by spores which disperse to new locations Sexual reproduction – Production of gametes – Spores and Gametes are produced by meiosis

Economic Importance Used as a food sources in China, Japan, and Korea Used as fertilizers, and in animal feeds Phycocolloids are used in food processing for their ability to form viscous suspensions – Algin- a phycocolloid that is used in ice cream, cheese, and baked goods. Also used in shampoos, paints, and cosmetics – Carrageenan- used as an emulsifier. Gives body to dairy products and pudding – Agar- Used to form jellies as a thickening agent. Also used as a medium to grow bacteria and molds.