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Actinia Sulcata
''Anemonia sulcata'', or Mediterranean snakelocks sea anemone, is a species of sea anemone in the family Actiniidae from the Mediterranean Sea. Whether ''A. sulcata'' should be recognized as a synonym of '' A. viridis'' remains a matter of dispute. Description This sea anemone has two ecotypes; one has a basal disk up to in diameter and has fewer than 192 tentacles (usually 142 to 148); the other has a disk up to in diameter and 192 tentacles or more, up to 348. The tentacles are long, slender and tapering, arranged in six whorls round the central mouth on the oral disk. They vary in colour but are usually some shade of green, grey or light brown. A knob on the tip of each tentacle, where the stinging cells are concentrated, may be violet. Distribution and habitat This sea anemone is native to the Mediterranean Sea and the eastern Atlantic Ocean as far south as Western Sahara. It is found in the intertidal zone and the sublittoral zone, on rocky ledges, in crevices and on b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argelès-sur-Mer
Argelès-sur-Mer (; ; ; ), commonly known as Argelès ( ), is a commune in the Pyrénées-Orientales department in the administrative region of Occitania, France. It is about 25 km from Perpignan. Geography Argelès-sur-Mer is located in the canton of La Côte Vermeille and in the arrondissement of Céret. Argelès-sur-Mer is on the Côte Vermeille at the foot of the Albères mountain range, close to the Spanish border. It has the longest beach in the Pyrenées Orientales. It is part of the Northern Catalan comarca of Rosselló. History In 1939, the Argelés concentration camp was created on the beaches near the town. At its peak in March 1939, the camp contained about 100,000 Spaniards, mostly soldiers of the defeated Spanish Republican Army. During World War II, Argelès-sur-Mer was the location of a concentration camp, where up to 100,000 defeated Spanish Republicans were interned next to a windy beach in abysmal sanitary conditions by the French government a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonad
A gonad, sex gland, or reproductive gland is a Heterocrine gland, mixed gland and sex organ that produces the gametes and sex hormones of an organism. Female reproductive cells are egg cells, and male reproductive cells are sperm. The male gonad, the testicle, produces sperm in the form of Spermatozoon, spermatozoa. The female gonad, the ovary, produces egg cells. Both of these gametes are haploid cells. Some hermaphroditic animals (and some humanssee Ovotesticular syndrome) have a type of gonad called an ovotestis. Evolution It is hard to find a common origin for gonads, but gonads most likely evolved independently several times. Regulation The gonads are controlled by luteinizing hormone (LH) and follicle-stimulating hormone (FSH), produced and secreted by gonadotropic cell, gonadotropes or gonadotrophins in the anterior pituitary gland. This secretion is regulated by gonadotropin-releasing hormone (GnRH) produced in the hypothalamus. Development The gonads develop f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cádiz (province)
Cádiz ( , , ) is a city in Spain and the capital of the Province of Cádiz in the autonomous community of Andalusia. It is located in the southwest of the Iberian Peninsula off the Atlantic Ocean separated from neighbouring San Fernando by a narrow isthmus. Cádiz, one of the oldest continuously inhabited cities in Western Europe, was founded by the Phoenicians as a trading post.Strabo, ''Geographica'' 3.5.5 In the 18th century, the Port in the Bay of Cádiz consolidated as the main harbour of mainland Spain, enjoying the virtual monopoly of trade with the Americas until 1778. It is also the site of the University of Cádiz. Situated on a narrow slice of land surrounded by the sea‚ Cádiz is, in most respects, a typical Andalusian city with well-preserved historical landmarks. The older part of Cádiz, within the remnants of the city walls, is commonly referred to as the Old Town (), and represents a large area of the total size of the city. It is characterized by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seafood
Seafood is any form of Marine life, sea life regarded as food by humans, prominently including Fish as food, fish and shellfish. Shellfish include various species of Mollusca, molluscs (e.g., bivalve molluscs such as clams, oysters, and mussels, and cephalopods such as octopus and squid), crustaceans (e.g. shrimp, crabs, and lobster), and echinoderms (e.g. sea cucumbers and sea urchins). Historically, marine mammals such as cetaceans (whales and dolphins) as well as Pinniped, seals have been eaten as food, though that happens to a lesser extent in modern times. Edible sea plants such as some Edible seaweed, seaweeds and microalgae are widely eaten as :edible seaweeds, sea vegetables around the world, especially in Asia. Seafood is an important source of (animal) protein in many Diet (nutrition), diets around the world, especially in coastal areas. Semi-vegetarianism, Semi-vegetarians who consume seafood as the only source of meat are said to adhere to pescetarianism. The harv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ortiguillas De Mar098
The snakelocks anemone (''Anemonia viridis'') is a sea anemone found in the eastern Atlantic Ocean and the Mediterranean Sea. The latter population is however sometimes considered a separate species, the Mediterranean snakelocks anemone (''A. sulcata''). The tentacles are usually a deep green color with purple tips. The green color is often attributed to the presence of symbiotic algae within the tentacles but is the result of the presence of green fluorescent protein which is present in corals, sea anemones, and some other cnidarians. The anemone tissue contains a symbiotic algae called zooxanthellae, which is necessary for the long-term survival of the sea anemone. When the numbers of algae diminish the anemone may appear dull grey. The algae need light to flourish, so snakelock anemones will be found in the sunniest pools. On average the snakelocks anemone is 8 cm wide. Reproduction Unlike other cnidarians, anemones (and other Anthozoa) entirely lack the free-swimming medu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Necrosis
Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who is often regarded as one of the founders of modern pathology. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated digestion of cell components. In contrast, ''apoptosis'' is a naturally occurring programmed and targeted cause of cellular death. While apoptosis often provides beneficial effects to the organism, necrosis is almost always detrimental and can be fatal. Cellular death due to necrosis does not follow the apoptotic signal transduction pathway, but rather various receptors are activated and result in the loss of cell membrane integrity and an uncontrolled release of products of cell death into the extracellular space. This initiates an inflammatory response in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidocyte
A cnidocyte (also known as a cnidoblast) is a type of cell containing a large secretory organelle called a ''cnidocyst'', that can deliver a sting to other organisms as a way to capture prey and defend against predators. A cnidocyte explosively ejects the toxin-containing cnidocyst which is responsible for the stings delivered by a cnidarian. The presence of this cell defines the phylum Cnidaria, which also includes the corals, sea anemones, hydrae, and jellyfish. Cnidocytes are single-use cells that need to be continuously replaced. Structure and function Each cnidocyte contains an organelle called a cnidocyst, which consists of a bulb-shaped capsule and a hollow, coiled tubule that is contained within. Immature cnidocytes are referred to as cnidoblasts or nematoblasts. The externally oriented side of the cell has a hair-like trigger called a cnidocil, a mechano-chemical receptor. When the trigger is activated, the tubule shaft of the cnidocyst is ejected and, in the case ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggregating Anemone
The aggregating anemone (''Anthopleura elegantissima''), or clonal anemone, is the most abundant species of sea anemone found on rocky, tide swept shores along the Pacific coast of North America. This cnidarian hosts endosymbiotic algae called zooxanthellae that contribute substantially to primary productivity in the intertidal zone. The aggregating anemone has become a model organism for the study of temperate cnidarian-algal symbioses. They are most well known for the ability to clone themselves. Description The polyps of the aggregating anemone reach up to eight cm across the oral disk with approximately 100 tentacles in three or four rows around the margins of the oral disk. Most are olive to bright green (depending on the species of algal symbionts present) with tentacles tipped in pink. Individuals that live in microhabitats that are deficient in photosynthetically active radiation (PAR), such as under docks or in caves, lack symbionts and are pale yellow to white in colo ... [...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 Vertebrate, 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. Some Monitor lizard, monitor lizards, including Komodo dragons, can reproduce asexually. While all prokaryotes reproduce without the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oocyte
An oocyte (, oöcyte, or ovocyte) is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female germ cells produce a primordial germ cell (PGC), which then undergoes mitosis, forming oogonia. During oogenesis, the oogonia become primary oocytes. An oocyte is a form of genetic material that can be collected for cryoconservation. Formation The formation of an oocyte is called oocytogenesis, which is a part of oogenesis. Oogenesis results in the formation of both primary oocytes during fetal period, and of secondary oocytes after it as part of ovulation. Characteristics Cytoplasm Oocytes are rich in cytoplasm, which contains yolk granules to nourish the cell early in development. Nucleus During the primary oocyte stage of oogenesis, the nucleus is called a germinal vesicle. The only normal human type of secondary oocyte has the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Column
The (oceanic) water column is a concept used in oceanography to describe the physical (temperature, salinity, light penetration) and chemical ( pH, dissolved oxygen, nutrient salts) characteristics of seawater at different depths for a defined geographical point. Generally, vertical profiles are made of temperature, salinity, chemical parameters at a defined point along the water column. The water column is the largest, yet one of the most under-explored, habitats on the planet; it is explored to better understand the ocean as a whole, including the huge biomass that lives there and its importance to the global carbon and other biogeochemical cycles. Studying the water column also provides understanding on the links between living organisms and environmental parameters, large-scale water circulation and the transfer of matter between water masses. Water columns are used chiefly for environmental studies evaluating the stratification or mixing of thermal or chemically stratif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Cavity
A body cavity is any space or compartment, or potential space, in an animal body. Cavities accommodate organs and other structures; cavities as potential spaces contain fluid. The two largest human body cavities are the ventral body cavity, and the dorsal body cavity. In the dorsal body cavity the brain and spinal cord are located. The membranes that surround the central nervous system organs (the brain and the spinal cord, in the cranial and spinal cavities) are the three meninges. The differently lined spaces contain different types of fluid. In the meninges for example the fluid is cerebrospinal fluid; in the abdominal cavity the fluid contained in the peritoneum is a serous fluid. In amniotes and some invertebrates the peritoneum lines their largest body cavity called the coelom. Mammals Mammalian embryos develop two body cavities: the intraembryonic coelom and the extraembryonic coelom (or chorionic cavity). The intraembryonic coelom is lined by somatic and s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
