PORTAGE LEARNING Study Resource NURS 231 - Detailed Correct Solutions

PORTAGE LEARNING Study Resource NURS 231 - Detailed Correct Solutions The hilus is a concave cleft, and it is at this point where the ureters, blood vessels, and nerves enter the kidney. - answer - Describe the location of the hilus and its significance. The function of the nephron is to control the concentration of water and soluble materials by filtering the blood, reabsorbing needed materials and excreting waste products as urine. The nephron thereby eliminates wastes from the body, regulates blood volume, pH and pressure, and controls the levels of electrolytes. - answer - Describe the functions of the nephron. Each nephron consists of two parts, the glomerular capsule (renal corpuscle) and the renal tubule. These two structures are connected (through the tubule) to the associated collecting ducts. The glomerular capsule (renal corpuscle) filters the blood, while the renal tubule reabsorbs needed materials, and the collecting ducts carry the remaining material away as urine to be excreted. - answer - Name the structures of the nephron and describe their individual functions. The outer cortex houses the glomeruli and convoluted tubules (proximal and distal) of the nephron as well as blood vessels. The inner medulla is comprised of the Loop of Henle of the nephron and cone-shaped masses also known as the renal pyramids. - answer - Compare and contrast the renal cortex and renal medulla. Discuss the structures found in each. Cortical nephrons make up 85% of all nephrons. They originate superficially in the cortex and have shorter loops of Henle that extend only a short distance into the medulla. Juxtamedullary nephrons make up the remaining 15% of all nephrons. They originate deeper in the cortex, and their loops of Henle are thinner and extend into the medulla entirely. - answer - Explain the difference between cortical nephrons and juxtamedullary nephrons. Nephrons receive their blood supply from 2 systems known as the glomerulus and peritubular capillary network. The glomerulus is a unique system in that it is located between 2 arterioles, afferent and efferent. Arterioles are high resistance vessels resulting in an extremely high-pressure system which can easily force fluid and solutes out of the blood into the glomerular capillary along its entire length. The peritubular capillaries are low-pressure vessels better suited for reabsorption as opposed to filtration. These capillaries surround the tubules in their entirety allowing rapid movement of solutes and water. - answer - Explain the differences in the two systems providing the blood supply to the nephron. How does their structure determine their role? Fenestrations and podocytes - answer - Name two specialized structures of the glomerular capillaries that contribute to the filtration of blood. (1) the proximal convoluted tubule (highly coiled) which drains Bowman capsule; (2) the loop of Henle; (3) the distal convoluted tubule; and (4) the collecting tubule which joins with other nephron tubules to collect the filtrate. - answer - List the 4 segments of the nephron tubule. (1) filtration (2) reabsorption and (3) secretion. Filtration takes place in the renal corpuscle; reabsorption and secretion occur in the renal tubules. - answer - What are the 3 processes involved in urine formation? Describe where they occur. A normal glomerular filtration rate (GFR) is 120-125 ml/min or 180 L/day. Maintenance of a relatively constant GFR is important for adequate reabsorption of water and other needed nutrients from the filtrate. - answer - What is the norm value for the GFR? Discuss why maintenance of this value is important. (1) renal autoregulation, (2) nervous system control, and (3) hormonal control. - answer - List the 3 regulatory mechanisms of the GFR. (1) through the renin-angiotensin-aldosterone system (RAA) (2) through the regulation of red blood cell production through the formation of erythropoietin, and (3) through calcium metabolism by the activation of