Unit 10: Marine Life

1. Unit 10:Marine Life The Primary Producers & Consumers

2. Phytoplankton, for the most part, are single celledplant-like organisms that drift near the ocean surface They are NOT plants!!!! Account for between 90 - 98% of ocean carbohydrate production. Almost invisible to the naked eye, but they are much more important to marine productivity than the larger and more conspicuous seaweeds. Seaweeds are larger marine plants more obvious Contribute only 2-10% of the ocean’s primary productivity. Chemosynthesis accounts for less than 1%. Biomass is the mass of living tissue in the area.

3. Factors that limit Productivity • Limiting factor is a physical or biological necessity whose presence in inappropriate amounts limits the normal actions of an organism. • Photosynthetic autotrophs require 4 things: 1. water 2. inorganic nutrients 3. carbon dioxide 4. sunlight

4. Ocean ---- water is not a limiting factor CO2 dissolves readily ---- not a limiting factor Potential limiting factors of primary productivity are nutrients and light. Inorganic nutrients are used to construct the larger organic molecules for primary productivity and to construct their skeleton and or shells. Nonconservative nutrients - nutrients that change in concentration with biological activity.

5. After a period of rapid phytoplankton growth (a phenomenon known as plankton bloom), the ocean surface is often drained of nonconservative nutrients (phosphates, nitrates and silicates). They become part of the producer or part of the animals that have eaten the producer. Lack of nutrients is the most common factor limiting primary productivity. If adequate nutrients are present, productivity depends on illumination.

6. Too little light limits productivity Too much light can slow and eliminate photosynthesis. Accessory pigments are light absorbing compounds closely associated with chlorophyll. Colors: brown, tan, olive, green, and red They will absorb light then transfer the energy to the chlorophyll when necessary.

7. Plankton • Planktos = wandering • Phytoplankton – plant-like members of the plankton community. • Zooplankton – animal-like members of the plankton community. • Plankton drifts or swims weakly • Go where the ocean goes • Unable to move consistently against waves or currents.

8. Only thing in common between various species…. • The only feature common to all plankton is their inability to make consistent lateral headway, although many will move vertically in the water column.

9. Many are in the 1-2 centimeter range. The largest drifters are the giant jellyfish, with a bell diameter of 3.5 meters. All plankton larger than about 1 centimeter across is called macroplankton The plankton that spends their lives within the plankton community are called holoplankton Some of the planktonic animals are the juvenile stages of crabs, barnacles, clams, seastars other organisms that will later adopt a benthic life style. These temporary visitors are Meroplankton Plankton Facts

10. Plankton • The diversity of plankton organisms is astonishing. • It can contain: a. giant drifting jellyfish (8meters) b. arrowworms c. single-celled creatures d. mollusks with slowly beating flaps e. crustaceans f. algae

11. Plankton will contain many different plant-like species and almost every different type of animal category. Members of the plankton community are referred to as plankters and do interact with each other (grazing, predators, parasites, and competition)

12. Algae • Simple plantlike autotroph • First plants on earth (900 million years old) • Non-vascular • Cell wall • Lack roots, stems and leaves • Must live in or near water • Three Phyla • Chlorophyta • Green algae • Rhodophyta • Red algae • Phaeophyta • Brown algae

13. Chlorophyta • Green algae • Main pigment – chlorophyll • Symbiotic with lichens and fungi • Store food as starch • 7,000 species • Most diverse group of algae

14. Rhodophyta • Red algae • Main pigment – phycoerythrin • Length reaches greatest depth out of all algae • 6,500-10,000 species (only 200 freshwater) • Used in foods • Ice cream, frosting, chocolate milk, dressing

15. Phaeophyta • Brown alage • Main pigment –fucoxanthin • Found in tropics • Eels lay eggs • Includes kelp

16. Phytoplankton • Autotrophic plankton - phytoplankton • (phyto = plant). • Autotrophic plankton is mostly single celled. • Live in marine and freshwater • It is critical to all life on earth because of • the great contribution to food webs • its generation of large amounts of atmospheric oxygen through photosynthesis. • 80% of the oxygen on earth • There are 8 types of phytoplankton. • The most important are: • dinoflagellates • diatoms • coccolithophores

17. Dinoflagellates

18. Single cell autotrophs Some live within the tissues of other organisms Majority live free in the water – solitary Most have 2 whip-like flagella (one for movement forward and one to make it spin) Outside “shell” of cellulose Reproduces by simple fission once a day Grow into large numbers Because of red accessory pigment, when they reproduce in large numbers, they cause a red tide (23 million/gal of water) Dinoflagellates

19. Bioluminescence - Dinoflagellates will take excess oxygen and combine it with enzymes and other proteins (Lucifer) to produce a glow. Some species synthesize an effective poison.

20. Most dominant photosynthetic organisms in the plankton community Most biochemically sophisticated Their abundance and photosynthetic efficiency further increased the proportion of free oxygen in the earth’s atmosphere. More than 5,000 species Rigid cell wall called a frustule consisting of silica. They are penetrated by perforations through the frustule (dia= through, tomos = to cut) They are round, elongated, branched or triangular. Diatoms

21. For the most effective light absorption, chlorophyll is accompanied in diatoms by accessory pigments called xanthophylls. Xanthophyllsare yellow or brown pigments and give most diatoms a yellow-green or tan appearance. Diatoms store energy as fatty acids and lipids. These are lighter than their equivalent volume of water which helps the diatoms to float.

23. Coccolithophores • Single celled • Covered with discs of calcium carbonate • Live near the ocean surface in brightly lighted areas • The calcium carbonate layer is translucent and acts as a sunshade • They can collect in such a number as to turn the water white or chalky • The white cliffs of Dover are deposits of Coccolithophores • They are referred to as nanoplankton due to their small size.

24. White Cliffs of Dover

25. The Primary Consumers Zooplankton

26. Zooplankton • Heterotrophic plankton • Most numerous of the primary consumers of the ocean • The most numerous of zooplankters are the Copepods • Crustaceans, a group that contains the crabs, lobsters and shrimp. • Not all zooplankters are small.