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Thirteen-lined Ground Squirrel
The thirteen-lined ground squirrel (''Ictidomys tridecemlineatus''), also known as the striped gopher, leopard ground squirrel, and squinny (formerly known as the leopard-spermophile in the age of John James Audubon, Audubon), is a species of hibernating ground squirrel that is widely distributed over grasslands and prairies of North America. Description It is brownish, with 13 alternating brown and whitish longitudinal lines (sometimes partially broken into spots) on its back and sides, creating rows of whitish spots within dark lines. Taxonomy This species has usually been placed in the genus ''Spermophilus'' with about 40 other species. As this large genus is paraphyly, paraphyletic to prairie dogs, marmots, and antelope squirrels, Kris Helgen, Kristofer Helgen and colleagues have split it into eight genera, placing the thirteen-lined ground squirrel in ''Ictidomys'' with two other species. Behavior The thirteen-lined ground squirrel is strictly Diurnal animal, diurn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel Latham Mitchill
Samuel Latham Mitchill (August 20, 1764September 7, 1831) was an American physician, naturalist, and politician who lived in Plandome, New York. Early life Samuel Mitchill was born in Hempstead in the Province of New York, the son of Robert Mitchill and his wife, Mary Latham, both Quakers. He was sent to Scotland and graduated in 1786 from the University of Edinburgh Medical School with an M.D., his education being paid for by a wealthy uncle. Returning to the United States after medical school, Mitchill also completed law school. As a lawyer, he oversaw the purchase of lands in western New York from the Iroquois Indians in 1788. Career Mitchill taught chemistry, botany, and natural history at Columbia College from 1792 to 1801 and was a founding editor of '' The Medical Repository'', the first medical journal in the United States. In 1793, he was elected a Foreign Fellow of the Royal Society of Edinburgh. His proposers were James Gregory, Dugald Stewart, and John Rother ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cricket (insect)
Crickets are orthopteran insects which are related to Tettigoniidae, bush crickets and more distantly, to grasshoppers. In older literature, such as Augustus Daniel Imms, Imms,Imms AD, rev. Richards OW & Davies RG (1970) ''A General Textbook of Entomology'' 9th Ed. Methuen 886 pp. "crickets" were placed at the family level (''i.e.'' Gryllidae), but contemporary authorities including Dan Otte, Otte now place them in the superfamily Grylloidea. The word has been used in combination to describe more distantly related taxa in the suborder Ensifera, such as Stenopelmatoidea, king crickets and mole crickets. Crickets have mainly cylindrically shaped bodies, round heads, and long antenna (biology), antennae. Behind the head is a smooth, robust pronotum. The abdomen ends in a pair of long Cercus, cerci; females have a long, cylindrical ovipositor. Diagnostic features include legs with 3-segmented Arthropod leg#Tarsus, tarsi; as with many Orthoptera, the hind legs have enlarged femora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fauna Of The Plains-Midwest (United States)
Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and ''funga'', respectively. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Modern Greek equivalent of fauna (πανίς or rather πανίδα). ''Fauna'' is also the word for a book ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodents Of The United States
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are native to all major land masses except for Antarctica, and several oceanic islands, though they have subsequently been introduced to most of these land masses by human activity. Rodents are extremely diverse in their ecology and lifestyles and can be found in almost every terrestrial habitat, including human-made environments. Species can be arboreal, fossorial (burrowing), saltatorial/ricochetal (leaping on their hind legs), or semiaquatic. However, all rodents share several morphological features, including having only a single upper and lower pair of ever-growing incisors. Well-known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters. Once included with rodents, rabbits, hares, and pikas, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ensembl
Ensembl genome database project is a scientific project at the European Bioinformatics Institute, which provides a centralized resource for geneticists, molecular biologists and other researchers studying the genomes of our own species and other vertebrates and model organisms. Ensembl is one of several well known genome browsers for the retrieval of genomic information. Similar databases and browsers are found at National Center for Biotechnology Information, NCBI and UCSC Genome Browser, the University of California, Santa Cruz (UCSC). History The human genome consists of three billion base pairs, which code for approximately 20,000–25,000 genes. However the genome alone is of little use, unless the locations and relationships of individual genes can be identified. One option is manual annotation, whereby a team of scientists tries to locate genes using experimental data from scientific journals and public databases. However this is a slow, painstaking task. The alternative, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chipmunk
Chipmunks are small, striped rodents of subtribe Tamiina. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia. Taxonomy and systematics Chipmunks are classified as four genera: ''Tamias'', of which the eastern chipmunk (''T. striatus'') is the only living member; ''Eutamias'', of which the Siberian chipmunk (''E. sibiricus'') is the only living member; ''Nototamias'', which consists of three extinct species, and ''Neotamias'', which includes the 23 remaining, mostly western North American, species. These classifications were treated as subgenera due to the chipmunks' morphological similarities. As a result, most taxonomies over the twentieth century have placed the chipmunks into a single genus. Joseph C. Moore reclassified chipmunks to form a subtribe Tamiina in a 1959 study, and this classification has been supported by studies of mitochondrial DNA. The common name originally may have been spelled "chitmunk", fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden-mantled Ground Squirrel
The golden-mantled ground squirrel (''Callospermophilus lateralis'') is a ground squirrel native to western North America. It is distributed in the Rocky Mountains of British Columbia and Alberta, and through much of the western United States. Description This ground squirrel is generally about in length. The weight range for adults is between 120 and 394 grams (0.26 to 0.86 lbs.) It has whitish or yellow-gray underparts. The tail is brown to black with buff edges and a yellowish to reddish underside. It has pale rings around the eyes. The "mantle" across the shoulders is tawny to reddish, with males having a deeper reddish tinge. This species is distinguished from similar ground squirrels by a black-bordered white stripe down each side of the back and is distinguished from similar looking chipmunks by its lack of facial stripes.Bartels, M. A. and D. P. Thompson''Spermophilus lateralis''. ''In'': Wilson, D. E. & D. M. Reeder (Eds). 2005. ''Mammal Species of the World. A Taxonomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycogen
Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. It is the main storage form of glucose in the human body. Glycogen functions as one of three regularly used forms of energy reserves, creatine phosphate being for very short-term, glycogen being for short-term and the triglyceride stores in adipose tissue (i.e., body fat) being for long-term storage. Protein, broken down into amino acids, is seldom used as a main energy source except during starvation and glycolytic crisis ''(see bioenergetic systems)''. In humans, glycogen is made and stored primarily in the cells of the liver and skeletal muscle. In the liver, glycogen can make up 5–6% of the organ's fresh weight: the liver of an adult, weighing 1.5 kg, can store roughly 100–120 grams of glycogen. In skeletal muscle, glycogen is found in a low concentration (1–2% of the muscle mass): the skeletal muscle of an adult weighing 70 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidative Damage
Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of cells can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA. Oxidative stress from oxidative metabolism causes base damage, as well as strand breaks in DNA. Base damage is mostly indirect and caused by the reactive oxygen species generated, e.g., (superoxide radical), OH (hydroxyl radical) and (hydrogen peroxide). Further, some reactive oxidative species act as cellular messengers in redox signaling. Thus, oxidative stress can cause disruptions in normal mechanisms of cellular signaling. In humans, oxidative stress is thought to be involved in the development of attention deficit hyperactivity disorder, cancer, Parkinson's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antioxidant
Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants are frequently added to industrial products, such as polymers, fuels, and lubricants, to extend their usable lifetimes. Foods are also treated with antioxidants to prevent Food spoilage, spoilage, in particular the rancidification of Vegetable oil, oils and fats. In Cell (biology), cells, antioxidants such as glutathione, mycothiol, or bacillithiol, and enzyme systems like superoxide dismutase, inhibit damage from oxidative stress. Known diet (nutrition), dietary antioxidants are vitamins vitamin A, A, vitamin C, C, and vitamin E, E, but the term has also been applied to various compounds that exhibit antioxidant properties in vitro, having little evidence for antioxidant properties in vivo. Dietary supplements marketed as antioxidants hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skeletal Muscle
Skeletal muscle (commonly referred to as muscle) is one of the three types of vertebrate muscle tissue, the others being cardiac muscle and smooth muscle. They are part of the somatic nervous system, voluntary muscular system and typically are attached by tendons to bones of a skeleton. The skeletal muscle cells are much longer than in the other types of muscle tissue, and are also known as ''muscle fibers''. The tissue of a skeletal muscle is striated muscle tissue, striated – having a striped appearance due to the arrangement of the sarcomeres. A skeletal muscle contains multiple muscle fascicle, fascicles – bundles of muscle fibers. Each individual fiber and each muscle is surrounded by a type of connective tissue layer of fascia. Muscle fibers are formed from the cell fusion, fusion of developmental myoblasts in a process known as myogenesis resulting in long multinucleated cells. In these cells, the cell nucleus, nuclei, termed ''myonuclei'', are located along the inside ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antidiuretic Hormone
Mammalian vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, is a hormone synthesized from the ''AVP'' gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then travels down the axon terminating in the posterior pituitary, and is released from vesicles into the circulation in response to extracellular fluid hypertonicity ( hyperosmolality). AVP has two primary functions. First, it increases the amount of solute-free water reabsorbed back into the circulation from the filtrate in the kidney tubules of the nephrons. Second, AVP constricts arterioles, which increases peripheral vascular resistance and raises arterial blood pressure. A third function is possible. Some AVP may be released directly into the brain from the hypothalamus, and may play an important role in social behavior, sexual motivation and pair bonding, and maternal responses to stress. Vasopressin induces differentiation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
