1. Plankton, Algae, and Plants

2. Plankton
Plankton: the mass of mostly microscopic organisms that float or drift freely in the waters of aquatic (freshwater and marine) environments. (Algae, phytoplankton, zooplankton, jellyfish).
The basis of all life in the ocean.
Make oxygen for us to breath.

3. Collecting and Studying Plankton
Plankton Nets: Conical nets made of nylon threads woven in a fine interlocking pattern. Hauled behind a ship or set to a certain depth and then reeled in.
Analyze plankton by counting how many there are, the types, and an estimate of the sample volume of water. Plankton per unit volume of water.
Why Study Plankton?
Plankton can tell us about the amount of dissolved oxygen, carbon dioxide, pH, temperature, and light intensity of the ocean at the time and place of sampling.

4. Phytoplankton: The Autotrophs
Generate sugar (glucose) by photosynthesis.
Make oxygen for us to breathe. 75% of Earth’s oxygen comes from phytoplankton in the ocean.
Live in Photic zone
Critical to marine life and life on Earth
Primary producers and bottom of food web
Generate oxygen

5. Types of Phytoplankton
Diatoms: Dominant and most productive.
Appeared in Cretaceous about 100 million years ago.
Contributed to Earth’s current atmospheric oxygen.
More than 5,600 known species!
Made of Silica
Dinoflagellates: Some live in corals. Others are free drifters.
Have flagella to propel them forward and rotate around. Can move vertically but not side to side.
Reproduce by division
Some are bioluminescent: Chemical reaction transformed into light (they glow!)
Numerous bioluminescent dinoflagellates cause “red tides” or harmful algal blooms.
Usually occurs in spring: Can reach 29 million organisms per gallon!

6. Red Tide

7. Types of Phytoplankton
Coccolithophores and Silicoflagellates:
Coccolithophores: Covered in disks of calcium carbonate (calcite).
Live near surface in brightly lit areas.
In Mediterranean, they make the water look milky because they are so abundant
Make up the famous White Cliffs of Dover in England (chalk)
Silicoflagellates: made of silica (quartz)
One or two flagella to move
Little is known about them
Picoplankton:
Extremely small
Contribute a lot of oxygen

8. Upwelling
Upwelling: the movement of deep, cold, and nutrient-rich water to the surface.
Organisms sink when they die. But these dead organisms are nutrient rich. They must be brought to the surface for other organisms to have food.
Sunlight is also a key factor.

9. Zooplankton: The Heterotrophs
Planktonic organisms that eat the primary producers
Most numerous primary consumers in the ocean
Eat diatoms, dinoflagellates, and other phytoplankton

10. Types of Zooplankton
Copepods: Tiny shrimp-like animals related to crabs, lobsters, and shrimp which are all crustaceans.
Make up 70% of zooplankton in the ocean
Jellyfish: Considered macroplankton because they are larger than 1 centimeter across.
Krill: Considered the keystone to the Arctic ecosystem. A shrimp-like crustacean that is eaten by seabirds, squids, fishes, and whales.
Travel in schools
Foraminifera (forams): Calcium Carbonate (calcite shells)
Related to amoebas