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Salmon Shark
The salmon shark (''Lamna ditropis'') is a species of Lamnidae, mackerel shark found in the northern Pacific ocean. As an apex predator, the salmon shark feeds on salmon, squid, sablefish, and herring. It is known for its ability to maintain stomach temperature (homeothermy), which is unusual among fish. This shark has not been demonstrated to maintain a constant body temperature. It is also known for an unexplained variability in the sex ratio between eastern and western populations in the northern Pacific. Description Adult salmon sharks are medium grey to black over most of the body, with a white underside with darker blotches. Juveniles are similar in appearance, but generally lack blotches. The snout is short and cone-shaped, and the overall appearance is similar to a small great white shark. The eyes are positioned well forward, enabling binocular vision to accurately locate prey. The salmon shark generally grows to between 200 and 260 cm (6.6–8.6 ft) in le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Leavitt Hubbs
Carl Leavitt Hubbs (October 19, 1894 – June 30, 1979) was an American ichthyologist. Biography Youth He was born in Williams, Arizona. He was the son of Charles Leavitt and Elizabeth (née Goss) Hubbs. His father had a wide variety of jobs (farmer, iron mine owner, newspaper owner). The family moved several times before settling in San Diego where he got his first taste of natural history. After his parents divorced in 1907, he lived with his mother, who opened a private school in Redondo Beach, California. His maternal grandmother Jane Goble Goss, one of the first female doctors, showed Hubbs how to harvest shellfish and other sea creatures. One of his teachers, impressed by Hubbs's abilities in science, recommended that he study chemistry at the University of Berkeley. The family moved once more to Los Angeles. In Los Angeles, George Bliss Culver, one of the many volunteers of David Starr Jordan, encouraged Hubbs to abandon his study of birds and instead to study fish, par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oophagy
Oophagy ( ) sometimes ovophagy, literally "egg eating", is the practice of embryos feeding on eggs produced by the ovary while still inside the mother's uterus. The word oophagy is formed from the classical Greek (, "egg") and classical Greek (, "to eat"). In contrast, adelphophagy is the cannibalism of a multi-celled embryo. Oophagy is thought to occur in all sharks in the order Lamniformes and has been recorded in the bigeye thresher (''Alopias superciliosus''), the pelagic thresher (''A. pelagicus''), the shortfin mako (''Isurus oxyrinchus'') and the porbeagle (''Lamna nasus'') among others. It also occurs in the tawny nurse shark (''Nebrius ferrugineus''), and in the family Pseudotriakidae. This practice may lead to larger embryos or prepare the embryo for a predatory lifestyle. There are variations in the extent of oophagy among the different shark species. The grey nurse shark (''Carcharias taurus'') practices intrauterine cannibalism, the first developed embryo consuming ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Stocks
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters (growth, recruitment, mortality and fishing mortality) are traditionally regarded as the significant factors determining the stock's population dynamics, while extrinsic factors (immigration and emigration) are traditionally ignored. Concepts The stock concept All species have geographic limits to their distribution, which are determined by their tolerance to environmental conditions, and their ability to compete successfully with other species. In marine environments this may be less evident than on land because there are fewer topographical boundaries, however, discontinuities still exist, produced for example by mesoscale and sub-mesoscale circulations that minimize long-distance dispersal of fish larvae. For fish, it is rare for an individual to reproduce randomly with all other individuals of that species within its biological range. There is a tendency to form a structur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epipelagic
The photic zone, euphotic zone, epipelagic zone, or sunlight zone is the uppermost layer of a body of water that receives sunlight, allowing phytoplankton to perform photosynthesis. It undergoes a series of physical, chemical, and biological processes that supply nutrients into the upper water column. The photic zone is home to the majority of aquatic life due to the activity (primary production) of the phytoplankton. Photosynthesis in photic zone In the photic zone, the photosynthesis rate exceeds the respiration rate. This is due to the abundant solar energy which is used as an energy source for photosynthesis by primary producers such as phytoplankton. These phytoplankton grow extremely quickly because of sunlight's heavy influence, enabling it to be produced at a fast rate. In fact, ninety five percent of photosynthesis in the ocean occurs in the photic zone. Therefore, if we go deeper, beyond the photic zone, such as into the compensation point, there is little to no phyto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmon Run
''Salmon Run'' is a 1982 video game for the Atari 8-bit family created by Bill Williams and distributed via the Atari Program Exchange. ''Salmon Run'' was the first game in Williams's career, followed by a string of successes noted for their oddball concepts. The player takes the role of Sam the Salmon, swimming upriver to mate. Along the way he encounters waterfalls, a bear, fishermen, and seagulls. In 1983, ''Salmon Run'' was released for the VIC-20 by Synapse Software Synapse Software Corporation (marketed as SynSoft in the UK) was an American video game development and publishing company founded in 1981 by Ihor Wolosenko and Ken Grant. It initially focused on the Atari 8-bit family, then later developed for th ... under the name Showcase Software. Gameplay ''Salmon Run'' is an overhead view, vertically scrolling game. As the river scrolls, the player primarily movesside-to-side to avoid obstacles. Each player starts with one life and gains another for each successful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prince William Sound
Prince William Sound (Sugpiaq: ''Suungaaciq'') is a sound of the Gulf of Alaska on the south coast of the U.S. state of Alaska. It is located on the east side of the Kenai Peninsula. Its largest port is Valdez, at the southern terminus of the Trans-Alaska Pipeline System. Other settlements on the sound, which contains numerous small islands, include Cordova and Whittier plus the Alaska native villages of Chenega and Tatitlek. History James Cook entered Prince William Sound in 1778 and initially named it Sandwich Sound, after his patron the Earl of Sandwich. Later that year, the Sound was named to honour George III's third son Prince William Henry, then aged 13 and serving as a midshipman in the Royal Navy. In 1790, the Spanish explorer Salvador Fidalgo entered the sound, naming many of its features. Some places in the sound still bear the names given by Fidalgo, as Port Valdez, Port Gravina or Cordova. The explorer landed on the actual site of Cordova and took possession of ... [...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] |
65th Parallel North
The 65th parallel north is a circle of latitude that is 65 degrees north of the Earth's equatorial plane. It crosses the Atlantic Ocean, Europe, Asia and North America. At this latitude the sun is visible for 22 hours, 4 minutes during the summer solstice and 3 hours, 35 minutes during the winter solstice. Around the world Starting at the Prime Meridian and heading eastwards, the parallel 65° north passes through: : See also *64th parallel north *66th parallel north The 66th parallel north is a circle of latitude that is 66 degrees north of the Earth's equatorial plane, about 61 km south of the Arctic Circle. It crosses the Atlantic Ocean, Europe, Asia and North America. This latitude also roughly ... {{geographical coordinates, state=collapsed n65 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Of Japan
The Sea of Japan is the marginal sea between the Japanese archipelago, Sakhalin, the Korean Peninsula, and the mainland of the Russian Far East. The Japanese archipelago separates the sea from the Pacific Ocean. Like the Mediterranean Sea, it has almost no tides due to its nearly complete enclosure from the Pacific Ocean. This isolation also affects faunal diversity and salinity, both of which are lower than in the open ocean. The sea has no large islands, bays or capes. Its water balance is mostly determined by the inflow and outflow through the straits connecting it to the neighboring seas and the Pacific Ocean. Few rivers discharge into the sea and their total contribution to the water exchange is within 1%. The seawater has an elevated concentration of dissolved oxygen that results in high biological productivity. Therefore, fishing is the dominant economic activity in the region. The intensity of shipments across the sea has been moderate owing to political issues, but it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ryanodine Receptor 2
Ryanodine receptor 2 (RYR2) is one of a class of ryanodine receptors and a protein found primarily in cardiac muscle. In humans, it is encoded by the ''RYR2'' gene. In the process of cardiac calcium-induced calcium release, RYR2 is the major mediator for sarcoplasmic release of stored calcium ions. Structure The channel is composed of RYR2 homotetramers and FK506-binding proteins found in a 1:4 stoichiometric ratio. Calcium channel function is affected by the specific type of FK506 isomer interacting with the RYR2 protein, due to binding differences and other factors. Function The RYR2 protein functions as the major component of a calcium channel located in the sarcoplasmic reticulum that supplies ions to the cardiac muscle during systole. To enable cardiac muscle contraction, calcium influx through voltage-gated L-type calcium channels in the plasma membrane allows calcium ions to bind to RYR2 located on the sarcoplasmic reticulum. This bindi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SERCA
SERCA, or sarco/endoplasmic reticulum Ca2+-ATPase, or SR Ca2+-ATPase, is a calcium ATPase-type P-ATPase. Its major function is to transport calcium from the cytosol into the sarcoplasmic reticulum. Function SERCA is a P-type ATPase. It resides in the sarcoplasmic reticulum (SR) within myocytes. It is a Ca2+ ATPase that transfers Ca2+ from the cytosol of the cell to the lumen of the SR. This uses energy from ATP hydrolysis during muscle relaxation. There are 3 major domains on the cytoplasmic face of SERCA: the phosphorylation and nucleotide-binding domains, which form the catalytic site, and the actuator domain, which is involved in the transmission of major conformational changes. In addition to its calcium-transporting functions, SERCA1 generates heat in brown adipose tissue and in skeletal muscles. Along with the heat it naturally produces due to its inefficiency in pumping ions, when it binds to a regulator called sarcolipin it stops pumping and functions solely as an AT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rete Mirabile
A rete mirabile (Latin for "wonderful net"; plural retia mirabilia) is a complex of arteries and veins lying very close to each other, found in some vertebrates, mainly warm-blooded ones. The rete mirabile utilizes countercurrent blood flow within the net (blood flowing in opposite directions) to act as a countercurrent exchanger. It exchanges heat, ions, or gases between vessel walls so that the two bloodstreams within the rete maintain a gradient with respect to temperature, or concentration of gases or solutes. This term was coined by Galen. Effectiveness The effectiveness of retia is primarily determined by how readily the heat, ions, or gases can be exchanged. For a given length, they are most effective with respect to gases or heat, then small ions, and decreasingly so with respect to other substances. The retia can provide for extremely efficient exchanges. In bluefin tuna, for example, nearly all of the metabolic heat in the venous blood is transferred to the arterial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
