The word “plankton” comes from the Greek for “drifter” or “wanderer.” An organism is considered plankton if it is carried by tides and currents, and cannot swim well enough to move against these forces.
Coral reefs are some of the most diverse ecosystems in the world. Thousands of species rely on reefs for survival. Millions of people all over the world also depend on coral reefs for food, protection and jobs. This tutorial is an overview of the biology of and threats to coral reefs, as well as efforts being made to conserve and protect them. It includes images, animations, and videos.
The surface layer of the ocean is teeming with photosynthetic plankton. Though they're invisible to the naked eye, they produce more oxygen than the largest redwoods. Scientists estimate that roughly half of the oxygen production on Earth comes from the ocean.
Phytoplankton, also known as microalgae, are similar to terrestrial plants in that they contain chlorophyll and require sunlight in order to live and grow. Most phytoplankton are buoyant and float in the upper part of the ocean, where sunlight penetrates the water. Phytoplankton also require inorganic nutrients such as nitrates, phosphates, and sulfur which they convert into proteins, fats ...
Activity Summary This activity is similar to Activity IV but adds more species and complexity to the system examined. Students will investigate the food web and trophic levels of another marine habitat, collect biomass data for multiple species in a kelp forest habitat in Monterey Bay, CA and compare the biomass data for species at different trophic levels. The key species in this activity are ...
Mermaids — those half-human, half-fish sirens of the sea — are legendary sea creatures chronicled in maritime cultures since time immemorial. The ancient Greek epic poet Homer wrote of them in The Odyssey. In the ancient Far East, mermaids were the wives of powerful sea-dragons, and served as trusted messengers between their spouses and the emperors on land. The aboriginal people of ...
Clams and mussels are often so inconspicuous and immobile that they can be mistaken for cobblestones; they are found on the bottom of waterbodies and feed by filtering water for microscopic plant and animal food particles (plankton).
Anything having a different density from the surrounding water (e.g., fish, plankton, air bubbles, the seafloor) can return a signal. In fish, the resonant swim bladder provides the greatest contrast from the water, and the larger the fish, the greater the strength of the returning echo.
Oceanography covers a wide range of topics, including marine life and ecosystems, ocean circulation, plate tectonics and the geology of the seafloor, and the chemical and physical properties of the ocean. Just as there are many specialties within the medical field, there are many disciplines within oceanography. Biological oceanographers and marine biologists study plants and animals in the ...
Winds drive ocean currents in the upper 100 meters of the ocean’s surface. However, ocean currents also flow thousands of meters below the surface. These deep-ocean currents are driven by differences in the water’s density, which is controlled by temperature (thermo) and salinity (haline). This process is known as thermohaline circulation. In the Earth's polar regions ocean water gets very ...
