The study of the origin, structure, development, growth, function, genetics, and reproduction of organisms which inhabit the OCEANS AND SEAS.

One of the BIOLOGICAL SCIENCE DISCIPLINES concerned with the origin, structure, development, growth, function, genetics, and reproduction of animals, plants, and microorganisms.

Organisms that live in water.

Comprehensive, methodical analysis of complex biological systems by monitoring responses to perturbations of biological processes. Large scale, computerized collection and analysis of the data are used to develop and test models of biological systems.

A great expanse of continuous bodies of salt water which together cover more than 70 percent of the earth's surface. Seas may be partially or entirely enclosed by land, and are smaller than the five oceans (Atlantic, Pacific, Indian, Arctic, and Antarctic).

Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES.

The phylum of sponges which are sessile, suspension-feeding, multicellular animals that utilize flagellated cells called choanocytes to circulate water. Most are hermaphroditic. They are probably an early evolutionary side branch that gave rise to no other group of animals. Except for about 150 freshwater species, sponges are marine animals. They are a source of ALKALOIDS; STEROLS; and other complex molecules useful in medicine and biological research.

A discipline concerned with studying biological phenomena in terms of the chemical and physical interactions of molecules.

The field of biology which deals with the process of the growth and differentiation of an organism.

The relationships of groups of organisms as reflected by their genetic makeup.

A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)

A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)

The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.

A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.

A field of biological research combining engineering in the formulation, design, and building (synthesis) of novel biological structures, functions, and systems.

Places for cultivation and harvesting of fish, particularly in sea waters. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.

Animals that have no spinal column.

Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

The variety of all native living organisms and their various forms and interrelationships.

Community of tiny aquatic PLANTS and ANIMALS, and photosynthetic BACTERIA, that are either free-floating or suspended in the water, with little or no power of locomotion. They are divided into PHYTOPLANKTON and ZOOPLANKTON.

The common name for the phylum of microscopic unicellular STRAMENOPILES. Most are aquatic, being found in fresh, brackish, and salt water. Diatoms are noted for the symmetry and sculpturing of their siliceous cell walls. They account for 40% of PHYTOPLANKTON, but not all diatoms are planktonic.

A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.

Free-floating minute organisms that are photosynthetic. The term is non-taxonomic and refers to a lifestyle (energy utilization and motility), rather than a particular type of organism. Most, but not all, are unicellular algae. Important groups include DIATOMS; DINOFLAGELLATES; CYANOBACTERIA; CHLOROPHYTA; HAPTOPHYTA; CRYPTOMONADS; and silicoflagellates.

A genus of VIBRIONACEAE, made up of short, slightly curved, motile, gram-negative rods. Various species produce cholera and other gastrointestinal disorders as well as abortion in sheep and cattle.

DNA sequences encoding RIBOSOMAL RNA and the segments of DNA separating the individual ribosomal RNA genes, referred to as RIBOSOMAL SPACER DNA.

One of the three domains of life (the others being BACTERIA and ARCHAEA), also called Eukarya. These are organisms whose cells are enclosed in membranes and possess a nucleus. They comprise almost all multicellular and many unicellular organisms, and are traditionally divided into groups (sometimes called kingdoms) including ANIMALS; PLANTS; FUNGI; and various algae and other taxa that were previously part of the old kingdom Protista.

Complex pharmaceutical substances, preparations, or matter derived from organisms usually obtained by biological methods or assay.

Multicellular marine macroalgae including some members of red (RHODOPHYTA), green (CHLOROPHYTA), and brown (PHAEOPHYTA) algae. They are widely distributed in the ocean, occurring from the tide level to considerable depths, free-floating (planktonic) or anchored to the substratum (benthic). They lack a specialized vascular system but take up fluids, nutrients, and gases directly from the water. They contain CHLOROPHYLL and are photosynthetic, but some also contain other light-absorbing pigments. Many are of economic importance as FOOD, fertilizer, AGAR, potash, or source of IODINE.

A group of the proteobacteria comprised of facultatively anaerobic and fermentative gram-negative bacteria.

The suborder of aquatic CARNIVORA comprising the WALRUSES; FUR SEALS; SEA LIONS; and EARLESS SEALS. They have fusiform bodies with very short tails and are found on all sea coasts. The offspring are born on land.

The protection, preservation, restoration, and rational use of all resources in the total environment.

One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.

Flagellate EUKARYOTES, found mainly in the oceans. They are characterized by the presence of transverse and longitudinal flagella which propel the organisms in a rotating manner through the water. Dinoflagellida were formerly members of the class Phytomastigophorea under the old five kingdom paradigm.

A class in the phylum MOLLUSCA comprised of mussels; clams; OYSTERS; COCKLES; and SCALLOPS. They are characterized by a bilaterally symmetrical hinged shell and a muscular foot used for burrowing and anchoring.

The science that deals with the ocean and its phenomena. (Webster, 3d ed)

A genus of GRAM-NEGATIVE AEROBIC BACTERIA of marine origin. Many species were formerly classified under ALTEROMONAS.

A class in the phylum PROTEOBACTERIA comprised mostly of two major phenotypes: purple non-sulfur bacteria and aerobic bacteriochlorophyll-containing bacteria.

A class in the phylum MOLLUSCA comprised of SNAILS and slugs. The former have coiled external shells and the latter usually lack shells.

Plants of the division Rhodophyta, commonly known as red algae, in which the red pigment (PHYCOERYTHRIN) predominates. However, if this pigment is destroyed, the algae can appear purple, brown, green, or yellow. Two important substances found in the cell walls of red algae are AGAR and CARRAGEENAN. Some rhodophyta are notable SEAWEED (macroalgae).

The most diversified of all fish orders and the largest vertebrate order. It includes many of the commonly known fish such as porgies, croakers, sunfishes, dolphin fish, mackerels, TUNA, etc.

Sulfur compounds in which the sulfur atom is attached to three organic radicals and an electronegative element or radical.

The sequence of transfers of matter and energy from organism to organism in the form of FOOD. Food chains intertwine locally into a food web because most organisms consume more than one type of animal or plant. PLANTS, which convert SOLAR ENERGY to food by PHOTOSYNTHESIS, are the primary food source. In a predator chain, a plant-eating animal is eaten by a larger animal. In a parasite chain, a smaller organism consumes part of a larger host and may itself be parasitized by smaller organisms. In a saprophytic chain, microorganisms live on dead organic matter.

A genus of obligately aerobic marine phototrophic and chemoorganotrophic bacteria, in the family RHODOBACTERACEAE.

A class of marine annelids including sandworms, tube worms, clamworms, and fire worms. It includes also the genus Myxicola infundibulum.

A division of predominantly marine EUKARYOTA, commonly known as brown algae, having CHROMATOPHORES containing carotenoid PIGMENTS, BIOLOGICAL. ALGINATES and phlorotannins occur widely in all major orders. They are considered the most highly evolved algae because of their well-developed multicellular organization and structural complexity.

Deoxyribonucleic acid that makes up the genetic material of bacteria.

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.

A phylum of the kingdom Metazoa. Mollusca have soft, unsegmented bodies with an anterior head, a dorsal visceral mass, and a ventral foot. Most are encased in a protective calcareous shell. It includes the classes GASTROPODA; BIVALVIA; CEPHALOPODA; Aplacophora; Scaphopoda; Polyplacophora; and Monoplacophora.

The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.

A class in the phylum CNIDARIA, comprised mostly of corals and anemones. All members occur only as polyps; the medusa stage is completely absent.

A body of water covering approximately one-fifth of the total ocean area of the earth, extending amidst Africa in the west, Australia in the east, Asia in the north, and Antarctica in the south. Including the Red Sea and the Persian Gulf, it constitutes the third largest ocean after the ATLANTIC OCEAN and the PACIFIC OCEAN. (New Encyclopaedia Britannica Micropaedia, 15th ed, 1990, p289)

A genus of GREEN ALGAE in the family Ulvaceae. Commonly know as sea lettuces, they grow attached to rocks and KELP in marine and estuarine waters.

The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)

Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.

A republic consisting of a group of about 100 islands and islets in the western Pacific Ocean. Its capital is Koror. Under Spain it was administered as a part of the Caroline Islands but was sold to Germany in 1899. Seized by Japan in 1914, it was taken by the Allies in World War II in 1944. In 1947 it became part of the U.S. Trust Territory of the Pacific Islands, became internally self-governing in 1980, obtained independent control over its foreign policy (except defense) in 1986, and achieved total independence October 1, 1994. (Webster's New Geographical Dictionary, 1988, p915; telephone communication with Randy Flynn, Board on Geographic Names, 17 January 1995)

The branch of science concerned with the interrelationship of organisms and their ENVIRONMENT, especially as manifested by natural cycles and rhythms, community development and structure, interactions between different kinds of organisms, geographic distributions, and population alterations. (Webster's, 3d ed)

Water containing no significant amounts of salts, such as water from RIVERS and LAKES.

An order of wholly aquatic MAMMALS occurring in all the OCEANS and adjoining seas of the world, as well as in certain river systems. They feed generally on FISHES, cephalopods, and crustaceans. Most are gregarious and most have a relatively long period of parental care and maturation. Included are DOLPHINS; PORPOISES; and WHALES. (From Walker's Mammals of the World, 5th ed, pp969-70)

Genes, found in both prokaryotes and eukaryotes, which are transcribed to produce the RNA which is incorporated into RIBOSOMES. Prokaryotic rRNA genes are usually found in OPERONS dispersed throughout the GENOME, whereas eukaryotic rRNA genes are clustered, multicistronic transcriptional units.

The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.

The continent lying around the South Pole and the southern waters of the Atlantic, Pacific, and Indian Oceans. It includes the Falkland Islands Dependencies. (From Webster's New Geographical Dictionary, 1988, p55)

A form-genus of spherical to rod-shaped CYANOBACTERIA in the order Chroococcales. They contain THYLAKOIDS and are found in a wide range of habitats.

A genus of marine planktonic CYANOBACTERIA in the order PROCHLOROPHYTES. They lack PHYCOBILISOMES and contain divinyl CHLOROPHYLL, a and b.

Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.