|
Black Katy Chiton
''Katharina tunicata'' (Wood, 1815) is commonly known as the black Katy chiton, black Leather chiton, black chiton, or leather chiton, (Kasuqix in the indigenous Aleut language), is a species of chiton in the family Mopaliidae. Description Capable of growing up to 12 cm, the animal is generally described as being football-shaped with a black leathery girdle in which are embedded eight protective plates. The parts of the plates that are visible are sometimes (but not always) diamond-shaped in outline. The underside of the animal is dull orange or yellow. Anatomy From the dorsal view, the mantle, girdle, and 8 valves are easily distinguishable. The girdle is covered with a chitinous cuticle. The ventral side shows the muscular foot surrounded by the gills on either side. This view also shows the mouth, anterior to the foot, and the anus, posterior to the foot encompassed by the mantle cavity and pallial fold which is then surrounded by the girdle. The gonopores are locat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Urchin
Sea urchins () are spiny, globular echinoderms in the class Echinoidea. About 950 species of sea urchin live on the seabed of every ocean and inhabit every depth zone from the intertidal seashore down to . The spherical, hard shells (tests) of sea urchins are round and spiny, ranging in diameter from . Sea urchins move slowly, crawling with tube feet, and also propel themselves with their spines. Although algae are the primary diet, sea urchins also eat slow-moving (sessile) animals. Predators that eat sea urchins include a wide variety of fish, starfish, crabs, marine mammals. Sea urchins are also used as food especially in Japan. Adult sea urchins have fivefold symmetry, but their pluteus larvae feature bilateral (mirror) symmetry, indicating that the sea urchin belongs to the Bilateria group of animal phyla, which also comprises the chordates and the arthropods, the annelids and the molluscs, and are found in every ocean and in every climate, from the tropics to the pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coastal Zone Management Act
The Coastal Zone Management Act of 1972 (CZMA; , , Chapter 33) is an Act of Congress passed in 1972 to encourage coastal states to develop and implement coastal zone management plans (CZMPs). This act was established as a United States National policy to preserve, protect, develop, and where possible, restore or enhance, the resources of the Nation's coastal zone for this and succeeding generations. History The Coastal Zone Management Act (CZMA) of 1972 showed that the United States Congress “recognized the importance of meeting the challenge of continued growth in the coastal zone”. Under this act two national programs were created, the National Coastal Zone Management Program (CZMP) and the National Estuarine Research Reserve System. Out of 35 eligible states, only 34 have established management programs; Washington State was the first state to adopt the program in 1976. The Coastal Zone Management Program (CZMP), also called the National Coastal Zone Management Program, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effects Of Climate Change
The effects of climate change impact the physical environment, ecosystems and human societies. The environmental effects of climate change are broad and far-reaching. They affect the water cycle, oceans, sea and land ice (glaciers), sea level, as well as weather and climate extreme events. The changes in climate are not uniform across the Earth. In particular, most land areas have warmed faster than most ocean areas, and the Arctic is warming faster than most other regions. The regional changes vary: at high latitudes it is the average temperature that is increasing, while for the oceans and tropics it is in particular the rainfall and the water cycle where changes are observed. The magnitude of future impacts of climate change can be reduced by climate change mitigation and adaptation. Climate change has degraded land by raising temperatures, drying soils and increasing wildfire risk. Recent warming has strongly affected natural biological systems. Species worldwide are mig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territories of the United States by population, most populous U.S. state and the List of U.S. states and territories by area, 3rd largest by area. It is also the most populated Administrative division, subnational entity in North America and the 34th most populous in the world. The Greater Los Angeles area and the San Francisco Bay Area are the nation's second and fifth most populous Statistical area (United States), urban regions respectively, with the former having more than 18.7million residents and the latter having over 9.6million. Sacramento, California, Sacramento is the state's capital, while Los Angeles is the List of largest California cities by population, most populous city in the state and the List of United States cities by population, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aleutian Islands
The Aleutian Islands (; ; ale, Unangam Tanangin,”Land of the Aleuts", possibly from Chukchi language, Chukchi ''aliat'', "island"), also called the Aleut Islands or Aleutic Islands and known before 1867 as the Catherine Archipelago, are a chain of 14 large volcanic islands and 55 smaller islands. Most of the Aleutian Islands belong to the U.S. state of Alaska, but some belong to the Russian Federal subjects of Russia, federal subject of Kamchatka Krai. They form part of the Aleutian Arc in the Northern Pacific Ocean, occupying a land area of 6,821 sq mi (17,666 km2) and extending about westward from the Alaska Peninsula toward the Kamchatka Peninsula in Russia, and act as a border between the Bering Sea to the north and the Pacific Ocean to the south. Crossing 180th meridian, longitude 180°, at which point east and west longitude end, the archipelago contains both the westernmost part of the United States by longitude (Amatignak Island) and the easternmost by longitude ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kamchatka Peninsula
The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and western coastlines, respectively. Immediately offshore along the Pacific coast of the peninsula runs the Kuril–Kamchatka Trench. The Kamchatka Peninsula, the Commander Islands, and the Karaginsky Island, constitute the Kamchatka Krai of the Russia, Russian Federation. The vast majority of the 322,079 inhabitants are ethnic Russians, although about 13,000 are Koryaks (2014). More than half of the population lives in Petropavlovsk-Kamchatsky (179,526 in 2010) and nearby Yelizovo (38,980). The Kamchatka peninsula contains the volcanoes of Kamchatka, a World Heritage Site, UNESCO World Heritage Site. Geography Politically, the peninsula forms part of Kamchatka Krai. The southern tip is called Cape Lopatka. (Lopatka is Russian for s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gametogenesis
Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes. Depending on the biological life cycle of the organism, gametogenesis occurs by meiotic division of diploid gametocytes into various gametes, or by mitosis. For example, plants produce gametes through mitosis in gametophytes. The gametophytes grow from haploid spores after sporic meiosis. The existence of a multicellular, haploid phase in the life cycle between meiosis and gametogenesis is also referred to as alternation of generations. It is the biological process of gametogenesis; cells that are haploid or diploid divide to create other cells. matured haploid gametes. It can take place either through mitosis or meiotic division of diploid gametocytes into different depending on an organism's biological life cycle, gametes. For instance, gametophytes in plants undergo mitosis to produce gametes. Both male and female have diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egg (biology)
An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the animal hatches. Most arthropods such as insects, vertebrates (excluding live-bearing mammals), and mollusks lay eggs, although some, such as scorpions, do not. Reptile eggs, bird eggs, and monotreme eggs are laid out of water and are surrounded by a protective shell, either flexible or inflexible. Eggs laid on land or in nests are usually kept within a warm and favorable temperature range while the embryo grows. When the embryo is adequately developed it hatches, i.e., breaks out of the egg's shell. Some embryos have a temporary egg tooth they use to crack, pip, or break the eggshell or covering. The largest recorded egg is from a whale shark and was in size. Whale shark eggs typically hatch within the mother. At and up to , the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamete
A gamete (; , ultimately ) is a haploid cell that fuses with another haploid cell during fertilization in organisms that reproduce sexually. Gametes are an organism's reproductive cells, also referred to as sex cells. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum— and a male produces the smaller type—called a sperm. Sperm cells or spermatozoa are small and motile due to the flagellum, a tail-shaped structure that allows the cell to propel and move. In contrast, each egg cell or ovum is relatively large and non-motile. In short a gamete is an egg cell (female gamete) or a sperm (male gamete). In animals, ova mature in the ovaries of females and sperm develop in the testes of males. During fertilization, a spermatozoon and ovum unite to form a new diploid organism. Gametes carry half the genetic information of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more chromosome sets. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in an organism's life cycle. Half ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioecious
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only about half the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fertilization including, for example, dichogamy, herkogamy, and self-incompatibility. Dioecy is a dimorphic sexual system, alongside gynodioecy and androdioecy. In zoology In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is either male or female, in which case the synonym gonochory is more often used. Most animal species are dioecious (gon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Gametogenesis")
