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Cyclosalpa Bakeri
''Cyclosalpa bakeri'' is a salp, a marine tunicate in the class Thaliacea. It is found floating in the open sea in the Indo-Pacific region. Description Like other salps, ''Cyclosalpa bakeri'' has two different phases. In one of these forms, individuals live a solitary life. They are cylindrical, transparent, gelatinous animals with a rather flabby test, growing to about 15 cm (6ins) long. There are openings at the anterior and posterior ends of the cylinder which can be opened or closed as needed. The bodies have seven transverse bands of muscle interspersed by white, translucent patches. A stolon grows from near the endostyle (an elongated glandular structure producing mucus for trapping food particles). The stolon is a ribbon-like organ on which a batch of aggregate forms of the animal are produced by budding. The aggregate is the second, colonial form of the salp and is also gelatinous, transparent and flabby. It takes the shape of a radial whorl of individuals up to abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Emerson Ritter
William Emerson Ritter (November 21, 1856 – January 10, 1944) was an American biologist. Ritter initiated and shaped the Marine Biological Association of San Diego (now Scripps Institution of Oceanography of UC San Diego) and the American Society for the Dissemination of Science (now the Society for Science and the Public and Science News). Innovative and entrepreneurial, with a deep desire for human service, he worked tirelessly to educate people in science thinking. He was the first biologist to propose a theory of systems, and seems to be the originator of the term organicism for biological purposes. Early life William Emerson Ritter was born on a farm on November 21, 1856 in Hampden Township, Columbia County, Wisconsin. His parents, Horatio and Leonora Ritter, moved from New York a few years earlier. The Ritter household included William, his brother Frank, his sisters Mary, Ella, and Flora, and his maternal grandparents, Nathan and Ruby Eason. For the first few years ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicata, tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called Gonochorism, gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siphonophorae
Siphonophorae (from Greek ''siphōn'' 'tube' + ''pherein'' 'to bear') is an order within Hydrozoa, which is a class of marine organisms within the phylum Cnidaria. According to the World Register of Marine Species, the order contains 175 species thus far. Although a siphonophore may appear to be an individual organism, each specimen is in fact a colonial organism composed of medusoid and polypoid zooids that are morphologically and functionally specialized. Zooids are multicellular units that develop from a single fertilized egg and combine to create functional colonies able to reproduce, digest, float, maintain body positioning, and use jet propulsion to move. Most colonies are long, thin, transparent floaters living in the pelagic zone. Like other hydrozoans, some siphonophores emit light to attract and attack prey. While many sea animals produce blue and green bioluminescence, a siphonophore in the genus ''Erenna'' was only the second life form found to produce a red li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterotracheoidea
The Pterotracheoidea is, according to the Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), a taxonomic superfamily of sea snails or sea slugs, marine gastropod molluscs in the clade Littorinimorpha. They are commonly called heteropods or sea elephants. Taxonomy This superfamily comprises four families (classification based on Newman (superfamily Carinarioidea, pp. 804–808. In: Beesley ''et al''., 1998), that is also used by the taxonomy of the Gastropoda by Bouchet & Rocroi (2005): * Family Pterotracheidae Rafinesque, 1814 * Family Atlantidae Rang, 1829 * † Family Bellerophinidae Destombes, 1984 * Family Carinariidae Blainville 1818 Habitat These holoplanktonic snails are found floating or swimming in tropical to subtropical open oceans and seas at a depth of maximum 200 to 300 m Anatomy These snails have adapted themselves to a pelagic living : * a transparent body and shell * the foot has evolved into a swimming fin that produces motion through undu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jellyfish
Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are anchored to the seabed by stalks rather than being mobile. The bell can pulsate to provide propulsion for highly efficient animal locomotion, locomotion. The tentacles are armed with Cnidocyte, stinging cells and may be used to capture prey and defend against predators. Jellyfish have a complex Biological life cycle, life cycle; the medusa is normally the sexual phase, which produces planula larvae that disperse widely and enter a sedentary polyp (zoology), polyp phase before reaching sexual maturity. Jellyfish are found all over the world, from surface waters to the deep sea. Scyphozoans (the "true jellyfish") are exclusively marine habitats, marine, but some hydrozoans with a simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algal Bloom
An algal bloom or algae bloom is a rapid increase or accumulation in the population of algae in freshwater or marine water systems. It is often recognized by the discoloration in the water from the algae's pigments. The term ''algae'' encompasses many types of aquatic photosynthetic organisms, both macroscopic multicellular organisms like seaweed and microscopic unicellular organisms like cyanobacteria. ''Algal bloom'' commonly refers to the rapid growth of microscopic unicellular algae, not macroscopic algae. An example of a macroscopic algal bloom is a kelp forest. Algal blooms are the result of a nutrient, like nitrogen or phosphorus from various sources (for example fertilizer runoff or other forms of nutrient pollution), entering the aquatic system and causing excessive growth of algae. An algal bloom affects the whole ecosystem. Consequences range from the benign feeding of higher trophic levels to more harmful effects like blocking sunlight from reaching other organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asexual Reproduction
Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the full set of genes of their single parent and thus the newly created individual is genetically and physically similar to the parent or an exact clone of the parent. Asexual reproduction is the primary form of reproduction for single-celled organisms such as archaea and eubacteria, bacteria. Many Eukaryote, eukaryotic organisms including plants, animals, and Fungus, fungi can also reproduce asexually. In vertebrates, the most common form of asexual reproduction is parthenogenesis, which is typically used as an alternative to sexual reproduction in times when reproductive opportunities are limited. Komodo dragons and some monitor lizards can also reproduce asexually. While all prokaryotes reproduce without the formation and fusion of gametes, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryo
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres are arranged as a solid ball that when reaching a certain size, called a morula, takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts of the body. Neurulation forms the nervous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis, as do trees and other plants on land. This means phytoplankton must have light from the sun, so they live in the well-lit surface layers (euphotic zone) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for about half of global photosynthetic activity and at least half of the oxygen production, despite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salp
A salp (plural salps, also known colloquially as “sea grape”) or salpa (plural salpae or salpas) is a barrel-shaped, planktic tunicate. It moves by contracting, thereby pumping water through its gelatinous body, one of the most efficient examples of jet propulsion in the animal kingdom. The salp strains the pumped water through its internal feeding filters, feeding on phytoplankton. Distribution Salps are common in equatorial, temperate, and cold seas, where they can be seen at the surface, singly or in long, stringy colonies. The most abundant concentrations of salps are in the Southern Ocean (near Antarctica), where they sometimes form enormous swarms, often in deep water, and are sometimes even more abundant than krill. Since 1910, while krill populations in the Southern Ocean have declined, salp populations appear to be increasing. Salps have been seen in increasing numbers along the coast of Washington. Life cycle Salps have a complex life cycle, with an obligatory a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., it borders the Canadian province of British Columbia and the Yukon territory to the east; it also shares a maritime border with the Russian Federation's Chukotka Autonomous Okrug to the west, just across the Bering Strait. To the north are the Chukchi and Beaufort Seas of the Arctic Ocean, while the Pacific Ocean lies to the south and southwest. Alaska is by far the largest U.S. state by area, comprising more total area than the next three largest states (Texas, California, and Montana) combined. It represents the seventh-largest subnational division in the world. It is the third-least populous and the most sparsely populated state, but by far the continent's most populous territory located mostly north of the 60th parallel, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
