Life in the Ocean

1) Plankton-drifters

2) Nekton- the swimmers

3) Benthic- bottom dwellers

Nekton = swimmers

Benthic = bottom dwellers

Plankton = drifters

Remember: Plankton

Plankton- organisms that are at the mercy of (drift with) the currents

Types of PlanktonThere are different classification schemes used to

categorize plankton

Plankton bloom during 1997 El Nino

Photosynthetic Ability

1)Phytoplankton- can photosynthesize

2) Zooplankton- do not photosynthesize

Phytoplankton

– The photosynthetic organisms that are very important in oxygen production, more so than terrestrial plants. (They produce most of the oxygen we breath!)

– Diatoms and dinoflagellates dominate the larger groups

– Nanophytoplankton are the most important photosynthetic organisms in the oceans

Diatoms- the earth’s most abundant, successful, and efficient single-celled phytoplankton

Diatoms- they have two interlocking valves made primarily of silica, and these valves contribute to sediments.

Dinoflagellates – class of microscopic single celled flagellates (have whip like tail for propelling)

Red TidesAlgae are responsible for red tides

Nanoplankton (or picoplankton)- very small phytoplankton (many species are this kind)

Zooplankton- animal members of the plankton community

• These are heterotrophs which means they do not produce their own food and rely on outside sources for nutrients

• These graze on the diatoms and dinoflagellates

• Shrimp like animals

(copepods) are the most

abundant

Foraminefera- planktonic amoeba like animals with a

calcium based shell

Extend filaments to snare food

Life History

We can also characterize plankton depending on whether it spends its whole life as plankton or only part of its life.

a) Holoplankton-entire life span is within the plankton community

Most zooplankton are this type

b) Meroplankton- part of the life span is within the plankton community, often the larvae stage of the nekton and benthic organisms

Planktonic mantis shrimp larvae

Tube anenome

Larval spiny lobster

Manta ray feeding on plankton

• Scientists developed a form of SCUBA diving called "blue-water diving" in order to observe plankton directly in the field.

• A group of divers are attached to a small boat via a "down-line“, leaving them free to collect and observe without the danger of floating too far from the boat or sinking too deep