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Specific Appetite
Specific appetite, also known as specific hunger, is a drive to eat foods with specific flavors or other characteristics. Regulation of homeostasis is essential to the survival of animals. Because the nutritional content of a diet will vary with environmental and other conditions, it is useful for animals to have a mechanism to ensure that their nutritional needs are within the appropriate range. Specific appetite is one such mechanism. Specific appetite has been demonstrated in various species for a number of vitamins and minerals, as well as calories, protein, and water. Unfortunately, specific appetite is very difficult to study experimentally, as there are a number of factors that influence food choice. Very little is known about the specific mechanisms inducing specific appetite, and the genes encoding for specific appetites are mostly speculative. Very few specific appetites for particular nutrients have been identified in humans. The most robustly identified are salt appetit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeostasis
In biology, homeostasis (British English, British also homoeostasis; ) is the state of steady internal physics, physical and chemistry, chemical conditions maintained by organism, living systems. This is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the pH of extracellular fluid, the concentrations of sodium, potassium, and calcium ions, as well as the blood sugar level, and these need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms, which together maintain life. Homeostasis is brought about by a natural resistance to change when already in optimal conditions, and equilibrium is maintained by many regulatory mechanisms; it is thought to be the central motivation for all organic action. All home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sucrose
Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined from either sugarcane or sugar beet. Sugar mills – typically located in tropical regions near where sugarcane is grown – crush the cane and produce raw sugar which is shipped to other factories for refining into pure sucrose. Sugar beet factories are located in temperate climates where the beet is grown, and process the beets directly into refined sugar. The Sugar refinery, sugar-refining process involves washing the raw sugar crystals before dissolving them into a sugar syrup which is filtered and then passed over carbon to remove any residual colour. The sugar syrup is then concentrated by boiling under a vacuum and crystallized as the final purification process to produce crystals of pure sucrose that are clear, odorless, and sweet. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein (nutrient)
Proteins are essential nutrients for the human body. They are one of the constituents of Tissue (biology), body tissue and also serve as a Fuel, fuel source. As fuel, proteins have the same energy density as carbohydrates: 17 Joule, kJ (4 Calories, kcal) per gram. The defining characteristic of protein from a nutritional standpoint is its amino acid composition. Proteins are polymer chains made of amino acids linked by peptide bonds. During human digestion, proteins are broken down in the stomach into smaller polypeptide chains via hydrochloric acid and protease actions. This is crucial for the absorption (small intestine), absorption of the essential amino acids that cannot be biosynthesized by the body. There are nine essential amino acids that humans must obtain from their diet to prevent protein–energy malnutrition, protein-energy malnutrition and resulting death. They are phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Congenital Adrenal Hyperplasia
Congenital adrenal hyperplasia (CAH) is a group of Genetic disorder#Autosomal recessive, autosomal recessive disorders characterized by impaired cortisol synthesis. It results from the deficiency of one of the five enzymes required for the Biosynthesis, synthesis of cortisol in the adrenal cortex. Most of these disorders involve excessive or deficient production of hormones such as glucocorticoids, mineralocorticoids, or sex steroids, and can alter development of primary sex characteristic, primary or secondary sex characteristics in some affected infants, children, or adults. It is one of the most common autosomal recessive disorders in humans. Types CAH can occur in various forms. The clinical presentation of each form is different and depends to a large extent on the underlying enzyme defect, its precursor retention, and deficient products. Classical forms appear in infancy and nonclassical forms appear in late childhood. The presentation in patients with classic CAH can be fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gitelman Syndrome
Gitelman syndrome (GS) is an autosomal recessive kidney tubule disorder characterized by low blood levels of potassium and magnesium, decreased excretion of calcium in the urine, and elevated blood pH. It is the most frequent hereditary salt-losing tubulopathy. Gitelman syndrome is caused by disease-causing variants on both alleles of the ''SLC12A3'' gene''.'' The ''SLC12A3'' gene encodes the thiazide-sensitive sodium-chloride cotransporter (also known as NCC, NCCT, or TSC), which can be found in the distal convoluted tubule of the kidney. Disease-causing variants in ''SLC12A3'' lead to a loss of NCC function, i.e., reduced transport of sodium and chloride via NCC. The effect is an electrolyte imbalance similar to that seen with thiazide diuretic therapy (which causes pharmacological inhibition of NCC activity). Gitelman syndrome was formerly considered a subset of Bartter syndrome until the distinct genetic and molecular bases of these disorders were identified. Signs and s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Health
Health has a variety of definitions, which have been used for different purposes over time. In general, it refers to physical and emotional well-being, especially that associated with normal functioning of the human body, absent of disease, pain (including mental pain), or injury. Health can be promoted by encouraging healthful activities, such as regular physical exercise and adequate sleep, and by reducing or avoiding unhealthful activities or situations, such as smoking or excessive stress. Some factors affecting health are due to individual choices, such as whether to engage in a high-risk behavior, while others are due to structural causes, such as whether the society is arranged in a way that makes it easier or harder for people to get necessary healthcare services. Still, other factors are beyond both individual and group choices, such as genetic disorders. History The meaning of health has evolved over time. In keeping with the biomedical perspective, earl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidney Dialysis
Kidney dialysis is the process of removing excess water, solutes, and toxins from the blood in people whose kidneys can no longer perform these functions naturally. Along with kidney transplantation, it is a type of renal replacement therapy. Dialysis may need to be initiated when there is a sudden rapid loss of kidney function, known as acute kidney injury (previously called acute renal failure), or when a gradual decline in kidney function, chronic kidney failure, reaches stage 5. Stage 5 chronic renal failure is reached when the glomerular filtration rate is less than 15% of the normal, creatinine clearance is less than 10 mL per minute, and uremia is present. Dialysis is used as a temporary measure in either acute kidney injury or in those awaiting kidney transplant and as a permanent measure in those for whom a transplant is not Indication (medicine), indicated or not possible.Pendse S, Singh A, Zawada E. "Initiation of Dialysis". In: ''Handbook of Dialysis''. 4th ed. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angiotensin
Angiotensin is a peptide hormone that causes vasoconstriction and an increase in blood pressure. It is part of the renin–angiotensin system, which regulates blood pressure. Angiotensin also stimulates the release of aldosterone from the adrenal cortex to promote sodium retention by the kidneys. An oligopeptide, angiotensin is a hormone and a dipsogen. It is derived from the precursor molecule angiotensinogen, a serum globulin produced in the liver. Angiotensin was isolated in the late 1930s (first named "angiotonin" or "hypertensin", later renamed "angiotensin" as a consensus by the 2 groups that independently discovered it) and subsequently characterized and synthesized by groups at the Cleveland Clinic and Ciba laboratories. Precursor and types Angiotensinogen Angiotensinogen is an α-2-globulin synthesized in the liver and is a precursor for angiotensin, but has also been indicated as having many other roles not related to angiotensin peptides. It is a member ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and used this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. Modern zoology has its origins during the Renaissance and early modern period, with Carl Linnaeus, Antonie van Leeuwenhoek, Robert Hooke, Charles Darwin, Gregor Mendel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Domesticated Animals
This page gives a list of domesticated animals, also including a list of domestication of animals, animals which are or may be currently undergoing the process of domestication and animals that have an extensive relationship with humans beyond simple predation. This includes species which are semi-domesticated, undomesticated but Captive breeding, captive-bred on a commercial scale, or commonly wild-caught, at least occasionally captive-bred, and Tame animal, tameable. In order to be considered fully domesticated, most species have undergone significant Heredity, genetic, Behavior, behavioural and Morphology (biology), morphological changes from their wild ancestors, while others have changed very little from their wild ancestors despite hundreds or thousands of years of potential selective breeding. A number of factors determine how quickly any changes may occur in a species, but there is not always a desire to improve a species from its wild form. Domestication is a gradual process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lipid Peroxidation
Lipid peroxidation, or lipid oxidation, is a complex chemical process that leads to oxidative degradation of lipids, resulting in the formation of peroxide and hydroperoxide derivatives.{{Cite journal , last1=Ayala , first1=Antonio , last2=Muñoz , first2=Mario F. , last3=Argüelles , first3=Sandro , date=2014 , title=Lipid Peroxidation: Production, Metabolism, and Signaling Mechanisms of Malondialdehyde and 4-Hydroxy-2-Nonenal , journal=Oxidative Medicine and Cellular Longevity , language=en , volume=2014 , pages=1–31 , doi=10.1155/2014/360438 , doi-access=free , issn=1942-0900 , pmc=4066722 , pmid=24999379 It occurs when free radicals, specifically reactive oxygen species (ROS), interact with lipids within cell membranes, typically polyunsaturated fatty acids (PUFAs) as they have carbon–carbon double bonds. This reaction leads to the formation of lipid radicals, collectively referred to as lipid peroxides or lipid oxidation products (LOPs), which in turn react with other ox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
