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McGraw Hill Financial, Inc. is an American publicly traded corporation headquartered in Rockefeller Center in New York City. Its primary areas of business are financial, publishing, and business services.
An order that includes over 20,000 species of terrestrial insects, including most of the “singing” insects, some of the world's largest insects, and some well-known pests. Most species of Orthoptera (from “orthos,” meaning straight, and “pteron,” meaning wing) have enlarged hind legs adapted for jumping. These include grasshoppers and locusts (in the suborder Caelifera, a mainly diurnal group); and the crickets, katydids (bush-crickets), New Zealand weta, and allied families (suborder Ensifera, which comprises mainly nocturnal species). Orthoptera share with other orthopteroid insects, such as mantids and stick insects (now in separate orders Mantodea and Phasmatodea), gradual metamorphosis, chewing mouthparts, and two pairs of wings, the anterior pair of which is usually thickened and leathery and covers the fanwise folded second pair. Wings are reduced or absent in many species. Characters that define the Orthoptera as a natural group (the inclusive set of all species stemming from a common ancestor) are the jumping hind legs, small and well-separated hind coxae (basal leg segments), a pronotum with large lateral lobes, and important molecular (genetic) characters. Food habits range from omnivorous to strictly carnivorous or herbivorous. Habitats are nearly all terrestrial, including arctic-alpine tundra and tropical areas with aquatic floating plants. Female orthopterans usually lay their eggs into soil or plant material. There are no parasitic species, but a few crickets live as cleptoparasitic “guests” in ant nests.
Industry:Science
An ordered array of DNA probes providing a powerful reagent for analyzing the genome. Recently, the completion of the analysis of the human genome has elucidated its entire sequence. DNA is the blueprint of life and encodes all of the genes that are expressed from the genome in the form of messenger ribonucleic acid (mRNA). The mRNA is translated by cellular machinery into proteins. Determining the sequence of the entire genome allows a comprehensive analysis of all genes, and hence proteins, that make up cells, tissues, and the entire organism. There is now access to the complete genome sequence of hundreds of bacteria and 25 eukaryotes, including yeast (<i>Saccharomyces cerevisiae</i>, 6200 genes encoded in about 12 million base pairs), worm (<i>Caenorhabditis elegans</i>, 18,000 genes encoded in about 80 million base pairs), fruit fly (about 200 million base pairs), and mouse (about 3 billion base pairs). As of 2003, highly accurate sequencing of the human genome (about 3 billion base pairs encoding an estimated 25,000 protein-coding genes) has been available.
Industry:Science
An organ involved with the elimination of water and waste products from the body. In vertebrates the kidneys are paired organs located close to the spine dorsal to the body cavity and are covered ventrally by the coelomic epithelium. They consist of a number of smaller functional units which are called urinary tubules or nephrons. The nephrons open to larger ducts, the collecting ducts, which open into a ureter. The two ureters run backward to open into the cloaca or into a urinary bladder. The shape and the location of the kidneys varies in different animals. In fish, they are extremely elongated and may reach forward almost to the pericardium. In reptiles, the kidneys are smaller and are located in the pelvic region. In mammals, they are bean-shaped and found between the thorax and the pelvis. The number, structure, and function of the nephrons vary with evolution and, in certain significant ways, with the adaptation of the animals to their various habitats.
Industry:Science
An organ located at the base of the oral cavity and found in all vertebrate animals. It is best developed in terrestrial vertebrates, where it takes on the functions of food procurement, food transport, and acquisition of chemosensory signals. The tongue generally is not a significant independent organ in fish, and it is secondarily reduced in organisms that feed aquatically, such as crocodilians and some turtles.
Industry:Science
An organ of the circulatory system present in most vertebrates, lying in the abdominal cavity usually in close proximity to the left border of the stomach. It exhibits wide variation in size, shape, color, and location, depending upon species and age.
Industry:Science
An organ utilized by the male animal for insemination, that is, to deposit spermatozoa directly into the female reproductive tract. Various types of copulatory organs are found among the vertebrates, whereas cloacal apposition occurs in most other vertebrates which lack these structures. Amplexus, or false copulation, is peculiar to amphibians.
Industry:Science
An organelle found in all eukaryotic cells and absent from prokaryotes such as bacteria. The Golgi apparatus is named after the Italian histologist Camillo Golgi, who visualized an “internal reticular apparatus” by light microscopy in 1898. This organelle consists of flattened membrane-bounded compartments known as cisternae. In most cells, the Golgi cisternae are organized into stacks. Different cell types contain from one to several thousand Golgi stacks. The Golgi apparatus sorts newly synthesized proteins for delivery to various destinations, and modifies the oligosaccharide chains found on glycoproteins and glycolipids.
Industry:Science
An organelle located in the cytoplasm of all animal cells and many plants, fungi, and protozoa, that controls the polymerization, position, and polar orientation of many of the cell's microtubules throughout the cell cycle. There is usually one centrosome per cell, located near the cell's center; it doubles during interphase, so there are two when the cell divides. At the onset of mitosis, each centrosome increases the number of microtubules it initiates. These mitotic microtubules are more labile and generally shorter than their interphase counterparts, and as they rapidly grow and shrink they probe the space around the centrosome that initiated them. When the nuclear envelope disperses, the microtubules extend from the centrosome into the former nucleoplasm where the chromosomes have already condensed. Some of these microtubules attach to the chromosomes, while others interact with microtubules produced by the sister centrosome, forming a mitotic spindle that organizes and segregates the chromosomes. During anaphase, sister centrosomes are forced apart as the spindle elongates, allowing each daughter cell to receive one centrosome to organize its microtubules in the next cell generation.
Industry:Science
An organic chemical reaction where one of the species, for example, the substrate, the reagent, or a catalyst, is bound to a cross-linked, and therefore insoluble, polymer support. A major attraction of polymer-supported reactions is that at the end of the reaction period the polymer-supported species can be separated cleanly and easily, usually by filtration, from the soluble species. This easy separation can greatly simplify product isolation procedures, and it may even allow the polymer-supported reactions to be automated. Often it is possible to reuse or recycle polymer-supported reactants. Partly for this reason and partly because they are insoluble, involatile, easily handled, and easily recovered, polymer-supported reactants are also attractive from an environmental point of view.
Industry:Science
An organic cofactor or prosthetic group (nonprotein portion of the enzyme) whose presence is required for the activity of many enzymes. In addition, many enzymes need metal ions, such as copper, manganese, and magnesium, for activation. The prosthetic groups attached to the protein of the enzyme (the apoenzyme) may be regarded as dissociable portions of conjugated proteins. The conenzymes usually contain vitamins as part of their structure. Neither the apoenzyme nor the coenzyme moieties can function singly, since dissociation of the two results in inactivation. In general, the coenzymes function as acceptors of electrons or functional groupings, such as the carboxyl groups in α-keto acids, which are removed from the substrate. Some of the well-known coenzymes are mentioned below.
Industry:Science
