what is the concentration gradient in the medulla of the urinary system?
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Along the loops of Henle within the kidney, the concentration gradient ranges from 300 - 1200 mosmol.  1200 mosmol occurs at the bottom of the loop.\n\nEverything you ever wanted to know:\nhttp://www.biol.sc.edu/courses/bio102/f99-44.html\n\nGood luck!
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The medulla oblongata is the lower portion of the brainstem, above the spinal cord, below the pons, and anterior to the cerebellum. It controls autonomic functions and relays nerve signals between the brain and spinal cord.
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water volume in your cells and thereby your tissues is at a higher than normal level.  so rather than the excess water leaving your body through urine, you are retaining it.  lack of adh can cause this, so can high salt intake etc.
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Hormone Control of Water and Salt \nWater reabsorption is controlled by the antidiuretic hormone (ADH) in negative feedback. ADH is released from the pituitary gland in the brain. Dropping levels of fluid in the blood signal the hypothalamus to cause the pituitary to release ADH into the blood. ADH acts to increase water absorption in the kidneys. This puts more water back in the blood, increasing the concentration of the urine. When too much fluid is present in the blood, sensors in the heart signal the hypothalamus to cause a reduction of the amounts of ADH in the blood. This increases the amount of water absorbed by the kidneys, producing large quantities of a more dilute urine.\n\nAldosterone, a hormone secreted by the kidneys, regulates the transfer of sodium from the nephron to the blood. When sodium levels in the blood fall, aldosterone is released into the blood, causing more sodium to pass from the nephron to the blood. This causes water to flow into the blood by osmosis. Renin is released into the blood to control aldosterone.
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A. Yes, the use of ATP against the gradient is active\nB. This is diffusion or osmosis\nC. Nope\nD. This is passive transport
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1.heart\nMain component of the circulatory system. It pumps blood to spread oxygen and nutrients to all over the body and to get some of the waste.\n2.Lungs\nTo take oxygen and put it in the blood.\n3Liver\nCleans toxins out of your body.\n4Kidneys\nThis one is my weakest answer - I know it helps filter your urine in some way.\n5.Stomach and intestines\nAbsorb nutrients from food.\n6.Mucles\nTo move.\n7.brain\nTo control the body.\n8.Bladder\nSo you don't piss yourself.
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urine is really excreted.\nThis occurs in the kidneys.\nThe Glomeruli are basically filters which don't let out blood cells or proteins. However the product of this filtration is then regulated by a series of tubules within the kidneys called the proximal and distal convoluted tubules and between them the loop of Henle. These control the resorption of important nutrients like glucose as well as the salt balance of the urine. They ensure the excretion of waste products like urea. This salt egulation is in turn regulated by the renin angiotensin/aldosterone sequence ofhormones that regulate sodium and potassium in the body. This is to ensure HOMEOSTASIS: a balanced blood plasma.\nThe end product, urine is excreted through the kidneys into the bladder and hence out of the body.\nKidneys, therefore do not just excrete urine: they purify plasma.
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Most of the sugar and protein constituents that pass through the glomerulus are absorbed back into the circulatory system.  Check out the following diagram on illustration of how the nephron works:\n\nhttp://www1.shore.net/~straub/labsk_nephron.gif
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Fluid inside the canals actually keeps your equilibrium in check. It is the equal amount of fluid which is sensed by your nervous system that tells your brain you're balanced, you're off balance, you're sideways, you're upside down, and all that jazz. Pretty nifty, huh? Over the years fluid starts to break down, but that my cyber-questioner is whole other question!
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Well absorbed in GIT.\nMostly metabolised, but 20% excreted unchanged in urine.\nRate of elimination increased by acidification of urine, but usually t1/2 = 6h.\nClearance reduced in CHF and liver disease (reduce dose by 25%).\nTarget plasma conc. is 3-6 micrograms/mL.\nHope that helped.
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INSIDE THE KIDNEY\nBowman's capsule--> Proximal convoluted tubule--> Loop of Henle--> Distal convoluted tube-->Collecting duct-->Renal pelvis\nKIDNEY TO ENVIRONMENT\nRenal pelvis-->Ureter-->Bladder-->Urethra* (Yahoo! won't spell out this word)
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Chemoreceptors in the medulla, carotid arteries and aorta, detect the levels of carbon dioxide in the blood. To do this, they monitor the concentration of hydrogen ions in the blood, which decreases the pH of the blood, as a direct consequence of the raised carbon dioxide concentration.\n\nThe response is that the inspiratory centre (in the medulla), sends nervous impulses to the external intercostal muscles and the diaphragm, via the phrenic nerve to increase breathing rate and the volume of the lungs during inhalation.
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Diffusion is simply the natural movement of ions and small molecules, usually from one side of a membrane to another, but also throughout a liquid. They always flow from more concentrated to less concentrated. So the concentration gradient between the cell and its environment determines which direction the molecules/ions move.
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Each kidney receives its blood supply from the renal artery, two of which branch from the abdominal aorta. Upon entering the hilum of the kidney, the renal artery divides into smaller interlobar arteries situated between the renal papillae. At the outer medulla, the interlobar arteries branch into arcuate arteries, which course along the border between the renal medulla and cortex, giving off still smaller branches, the cortical radial arteries (sometimes called interlobular arteries). Branching off these cortical arteries are the afferent arterioles supplying the glomerular capillaries, which drain into efferent arterioles. Efferent arterioles divide into peritubular capillaries that provide an extensive blood supply to the cortex. Blood from these capillaries collects in renal venules and leaves the kidney via the renal vein. Efferent arterioles of glomeruli closest to the medulla (those that belong to juxtamedullary nephrons) send branches into the medulla, forming the vasa recta. Blood supply is intimately linked to blood pressure.\n\n\n[edit] Nephron\n \n1. Renal pyramid\n2. Efferent artery\n3. Renal artery\n4. Renal vein\n5. Renal hilum\n6. Renal pelvis\n7. Ureter\n8. Minor calyx\n9. Renal capsule\n10. Inferior renal capsule\n11. Superior renal capsule\n12. Afferent vein\n13. Nephron\n14. Minor calyx\n15. Major calyx\n16. Renal papilla\n17. Renal columnMain article: Nephron\nThe basic functional unit of the kidney is the nephron, of which there are more than a million within the cortex and medulla of each normal adult human kidney. Nephrons regulate water and soluble matter (especially electrolytes) in the body by first filtering the blood under pressure, and then reabsorbing some necessary fluid and molecules back into the blood while secreting other, unneeded molecules. Reabsorption and secretion are accomplished with both cotransport and countertransport mechanisms established in the nephrons and associated collecting ducts.\n\n\n[edit] Collecting duct system\nMain article: Collecting duct system\nThe fluid flows from the nephron into the collecting duct system. This segment of the nephron is crucial to the process of water conservation by the organism. In the presence of antidiuretic hormone (ADH; also called vasopressin), these ducts become permeable to water and facilitate its reabsorption, thus concentrating the urine and reducing its volume. Conversely, when the organism must eliminate excess water, such as after excess fluid drinking, the production of ADH is decreased and the collecting tubule becomes less permeable to water, rendering urine dilute and abundant. Failure of the organism to decrease ADH production appropriately may lead to water retention and dangerous dilution of body fluids, which in turn may cause severe neurological damage. Failure to produce ADH (or inability of the collecting ducts to respond to it) may cause excessive urination, called diabetes insipidus.\n\nAfter being processed along the collecting tubules and ducts, the fluid, now called urine, is drained into the bladder via the ureter, to be finally excluded from the organism\n\nBlood Pressure\n\nSodium ions are controlled in a homeostatic process involving aldosterone which increases sodium ion absorption in the distal convoluted tubules.\n\nWhen blood pressure becomes low, a proteolytic enzyme called Renin is secreted by cells of the juxtaglomerular apparatus (part of the distal convoluted tubule) which are sensitive to pressure. Renin acts on a blood protein, angiotensinogen, converting it to angiotensin I (10 amino acids). Angiotensin I is then converted by the Angiotensin converting enzyme (ACE) in the lung capillaries to Angiotensin II (8 amino acids), which stimulates the secretion of Aldosterone by the adrenal cortex, which then affects the kidney tubules.\n\nAldosterone stimulates an increase in the reabsorption of sodium ions from the kidney tubules which causes an increase in the volume of water that is reabsorbed from the
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well,ureteric is anything that related to the URETER e.g ureteric orifice,here is some information:\n*the ureters are the ducts that carry urine from the kidneys to the urinary bladder,the ureters are muscular tubes that can propel urine along by the motions of peristalsis,in the adult,the ureters are usually 25 to 35cm long,in humans,the ureters enter the bladder posteriorly, running within the wall of the bladder for a few centimetres,there are no valves in the ureters,backflow being prevented by pressure from the filling of the bladder,as well as the tone of the muscle in the bladder wall.
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to maintain the concentration level of the cell
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I think D is incorrect.  The inside of the cell is negative compared to the outside of the cell.  Therefore, the electrical gradient of Na+ would want to move Na+ into the cell.