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Cassiopea Xamachana
''Cassiopea xamachana'', commonly known as the upside-down jellyfish, is a species of jellyfish in the family Cassiopeidae. It is found in warm parts of the western Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico. It was first described by the American marine biologist Henry Bryant Bigelow in 1892. Description The medusa phase of ''Cassiopea xamachana'' can grow to a diameter of about . Compared to most species of jellyfish it is upside-down, that is to say the bell, which is saucer-shaped, is underneath and acts like a suction cup to stabilise the jellyfish on the seabed. The four pairs of much-branched tentacles are on the upperside. Instead of a central mouth, there are numerous oral openings in the tentacles which connect via channels to the stomach. The mesogloea, the jelly-like tissue, contains symbiotic zooxanthellae, single-celled protists, which are photosynthetic and give the jellyfish its variable color, often bluish-grey or bluish-green. Distribution an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Bryant Bigelow
Henry Bryant Bigelow (October 3, 1879 – December 11, 1967) was an American oceanographer and marine biologist. He is the grandson of Henry Bryant who was an American physician and naturalist. After graduating from Harvard in 1901, he began working with famed ichthyologist Alexander Agassiz. Bigelow accompanied Agassiz on several major marine science expeditions including one aboard the ''Albatross'' in 1907. He began working at the Museum of Comparative Zoology in 1905 and joined Harvard's faculty in 1906 where he worked for 62 years. In 1911, Bigelow was elected a Fellow of the American Academy of Arts and Sciences. He helped found the Woods Hole Oceanographic Institution in 1930 and was its founding director. During his life he published more than one hundred papers and several books. He was a world-renowned expert on coelenterates and elasmobranchs. In 1948 Bigelow was awarded the Daniel Giraud Elliot Medal from the National Academy of Sciences. Honors The Henry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidocyte
A cnidocyte (also known as a cnidoblast or nematocyte) is an explosive cell containing one large secretory organelle called a cnidocyst (also known as a cnida () or nematocyst) that can deliver a sting to other organisms. The presence of this cell defines the phylum Cnidaria (corals, sea anemones, hydrae, jellyfish, etc.). Cnidae are used to capture prey and as a defense against predators. A cnidocyte fires a structure that contains a toxin within the cnidocyst; this is responsible for the stings delivered by a cnidarian. Structure and function Each cnidocyte contains an organelle called a cnida, cnidocyst, nematocyst, ptychocyst or spirocyst. This organelle consists of a bulb-shaped capsule containing a coiled hollow tubule structure attached to it. An immature cnidocyte is referred to as a cnidoblast or nematoblast. The externally oriented side of the cell has a hair-like trigger called a cnidocil, which is a mechano- and chemo-receptor. When the trigger is activated, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poseidon
Poseidon (; grc-gre, Ποσειδῶν) was one of the Twelve Olympians in ancient Greek religion and myth, god of the sea, storms, earthquakes and horses.Burkert 1985pp. 136–139 In pre-Olympian Bronze Age Greece, he was venerated as a chief deity at Pylos and Thebes. He also had the cult title "earth shaker". In the myths of isolated Arcadia he is related with Demeter and Persephone and he was venerated as a horse, however, it seems that he was originally a god of the waters.Seneca quaest. Nat. VI 6 :Nilsson Vol I p.450 He is often regarded as the tamer or father of horses, and with a strike of his trident, he created springs which are related to the word horse.Nilsson Vol I p.450 His Roman equivalent is Neptune. Poseidon was the protector of seafarers, and of many Hellenic cities and colonies. Homer and Hesiod suggest that Poseidon became lord of the sea when, following the overthrow of his father Cronus, the world was divided by lot among Cronus' three sons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andromeda (mythology)
In Greek mythology, Andromeda (; grc, Ἀνδρομέδα, Androméda or , ''Andromédē'') is the daughter of the king of Aethiopia, Cepheus, and his wife, Cassiopeia. When Cassiopeia boasts that she is more beautiful than the Nereids, Poseidon sends the sea monster Cetus to ravage the coast of Aethiopia as divine punishment. Andromeda is chained to a rock as a sacrifice to sate the monster, but is saved from death by Perseus, who marries her and takes her to Greece to reign as his queen. As a subject, Andromeda has been popular in art since classical times; rescued by a Greek hero, Andromeda's narration is considered the forerunner to the " princess and dragon" motif. From the Renaissance, interest revived in the original story, typically as derived from Ovid's ''Metamorphoses'' (4.663ff). Etymology Her name is the Latinized form of the Greek (''Androméda'') or (''Andromédē'') 'ruler of men', from (''anēr, andrós'') meaning 'man, husband, human being', and (''med ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassiopeia (mother Of Andromeda)
Cassiopeia (; Ancient Greek: Κασσιόπεια ''Kassiópeia'' or ''Kassiópē'') or Cassiepeia (Κασσιέπεια ''Kassiépeia''), a figure in Greek mythology, was Queen of Aethiopia and wife of King Cepheus. She was arrogant and vain, characteristics that led to her downfall. Family Her origins are obscure. Nonnus calls her a nymph, while according to Stephanus, she was called Iope, the daughter of Aeolus, from whom the town of Joppa (now the Jaffa neighborhood in Tel Aviv) derived its name. Mythology Cassiopeia boasted that she and her daughter Andromeda were more beautiful than all the Nereids, the nymph-daughters of the sea god Nereus. This brought the wrath of Poseidon, ruling god of the sea, upon the kingdom of Ethiopia. Accounts differ as to whether Poseidon decided to flood the whole country or direct the sea monster Cetus to destroy it. In either case, trying to save their kingdom, Cepheus and Cassiopeia consulted a wise oracle, who told them that the on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Geographic
''National Geographic'' (formerly the ''National Geographic Magazine'', sometimes branded as NAT GEO) is a popular American monthly magazine published by National Geographic Partners. Known for its photojournalism, it is one of the most widely read magazines of all time. The magazine was founded in 1888 as a scholarly journal, nine months after the establishment of the society, but is now a popular magazine. In 1905, it began including pictures, a style for which it became well-known. Its first color photos appeared in the 1910s. During the Cold War, the magazine committed itself to present a balanced view of the physical and human geography of countries beyond the Iron Curtain. Later, the magazine became outspoken on environmental issues. Since 2019, controlling interest has been held by The Walt Disney Company. Topics of features generally concern geography, history, nature, science, and world culture. The magazine is well known for its distinctive appearance: a thick s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cilia
The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projection that extends from the surface of the much larger cell body. Eukaryotic flagella found on sperm cells and many protozoans have a similar structure to motile cilia that enables swimming through liquids; they are longer than cilia and have a different undulating motion. There are two major classes of cilia: ''motile'' and ''non-motile'' cilia, each with a subtype, giving four types in all. A cell will typically have one primary cilium or many motile cilia. The structure of the cilium core called the axoneme determines the cilium class. Most motile cilia have a central pair of single microtubules surrounded by nine pairs of double microtubules called a 9+2 axoneme. Most non-motile cilia have a 9+0 axoneme that lacks the central pai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucus
Mucus ( ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It is a viscous colloid containing inorganic salts, antimicrobial enzymes (such as lysozymes), immunoglobulins (especially IgA), and glycoproteins such as lactoferrin and mucins, which are produced by goblet cells in the mucous membranes and submucosal glands. Mucus serves to protect epithelial cells in the linings of the respiratory, digestive, and urogenital systems, and structures in the visual and auditory systems from pathogenic fungi, bacteria and viruses. Most of the mucus in the body is produced in the gastrointestinal tract. Amphibians, fish, snails, slugs, and some other invertebrates also produce external mucus from their epidermis as protection against pathogens, and to help in movement and is also produced in fish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strobilation
Strobilisation or transverse fission is a form of asexual reproduction consisting of the spontaneous transverse segmentation of the body. It is observed in certain cnidarians and helminths. This mode of reproduction is characterized by high offspring output, which, in the case of the parasitic tapeworms, is of great significance. Strobilation in cnidarians *The process starts with preliminary morphological changes. In particular, the cnidarian's tentacles tend to be reabsorbed. *Neck-formation: transverse constrictions appear near the upper extremity of the animal. A strobilating polyp is called a strobila while the non-strobilating polyp is called a scyphistoma or scyphopolyp. *Segmentation: the number of constriction sites increases and migrates down the body length, transforming the body into a sequence of disks. The fissures intensify until the initial body is divided into equally spaced, separate segments. The oral end of the polyp becomes the oral end of the ephyra. *Metamor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some insects, fish, amphibians, mollusks, crustaceans, cnidarians, echinoderms, and tunicates undergo metamorphosis, which is often accompanied by a change of nutrition source or behavior. Animals can be divided into species that undergo complete metamorphosis (" holometaboly"), incomplete metamorphosis (" hemimetaboly"), or no metamorphosis (" ametaboly"). Scientific usage of the term is technically precise, and it is not applied to general aspects of cell growth, including rapid growth spurts. Generally organisms with a larva stage undergo metamorphosis, and during metamorphosis the organism loses larval characteristics. References to "metamorphosis" in mammals are imprecise and only colloquial, but historically idealist ideas of transformatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizophora Mangle
''Rhizophora mangle'', the red mangrove, is distributed in estuarine ecosystems throughout the tropics. Its viviparous "seeds", in actuality called propagules, become fully mature plants before dropping off the parent tree. These are dispersed by water until eventually embedding in the shallows. ''Rhizophora mangle'' grows on aerial prop roots, which arch above the water level, giving stands of this tree the characteristic "mangrove" appearance. It is a valuable plant in Florida, Louisiana, and Texas coastal ecosystems. In its native habitat it is threatened by invasive species such as the Brazilian pepper tree ''(Schinus terebinthifolius)''. The red mangrove itself is considered an invasive species in some locations, such as Hawaii, where it forms dense, monospecific thickets. ''R. mangle'' thickets, however, provide nesting and hunting habitat for a diverse array of organisms, including fish, birds, and crocodiles. Distribution and habitat Red mangroves are found in su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biology)
In biology, a substrate is the surface on which an organism (such as a plant, fungus, or animal) lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock (its substrate) can be itself a substrate for an animal that lives on top of the algae. Inert substrates are used as growing support materials in the hydroponic cultivation of plants. In biology substrates are often activated by the nanoscopic process of substrate presentation. In agriculture and horticulture * Cellulose substrate * Expanded clay aggregate (LECA) * Rock wool * Potting soil * Soil In animal biotechnology Requirements for animal cell and tissue culture Requirements for animal cell and tissue culture are the same as described for plant cell, tissue and organ culture (In Vitro Culture Techniques: The Biotechnological Principles). Desirable requirements are (i) air conditioning of a room, (ii) hot room with temperature recorder, (iii) microsc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
