From The American Heritage® Student Science Dictionary
, The American Heritage® Children's Science Dictionary
, and other sources.
current A flowing movement in a liquid or gas, especially one that follows a recognizable course. Ocean currents are rivers of hot or cold seawater within the ocean. The currents are generated by a number of forces acting upon the water including the planet's rotation, wind, temperature, and the moon's gravity. Currents have a strong influence on climate.
edible Something that can be eaten safely. The term is also often used to refer to how something tastes.
jellyfish Any of numerous invertebrate marine animals having a soft, often umbrella-shaped body with stinging tentacles around a central mouth. Jellyfish are cnidarians and are related to the hydras and corals. Many jellyfish go through two distinct phases of life. In the early stages of life, the jellyfish settle down in one spot and are called polyps. Many mature into the medusa form and become free-swimming as adults. Some jellyfish do not go through a polyp stage.
life cycle The series of changes in the growth and development of an organism from its beginning as an independent life form to its mature state in which offspring are produced.
nematocyst One of the stinging cells in the tentacles of a jellyfish, hydra, or related animal, used to capture prey and ward off attackers.
population A group of individuals of the same species occupying a specific habitat, community, or other defined area. For example, the number of turtles in a pond; the elk population in their winter range.
swarm A large number of living or non-living things massed together and usually in motion. Often used to refer to a great number of honeybees moving out of a hive to start a new colony.
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