FINAL Exam Biology A&P 2 questions and answers well illustrated.

FINAL Exam Biology A&P 2 questions and answers well illustrated. Why are the kidneys said to be retroperitoneal? - correct answers.Their position in the body is posterior to the peritoneum of the abdominal cavity What structures pass through the renal hilus? - correct answers.Ureter, renal artery, renal vein, lymphatic vessels, nerves. What volume of blood enters the renal arteries per minutes? - correct answers.At rest about 20-25% cardiac output flows through the kidneys. This is on the order of 1200ml each minute. What are the basic differences between cortical and juxtamedullary nephrons? - correct answers.Cortical nephrons: most numerous type, renal corpuscles in outer portion of renal cortex, short loops of Henle lying mainly in cortex and penetrate only into outer region of medulla, loop blood supply is from peritubular capillaries juxtamedullary nephrons: least numerous, corpuscles lie deep in cortex close to medulla, long loop of henle extending into deepest region of medulla, loop blood supply from vasa recta Where is the juxtaglomerular apparatus (JGA) located and what is its structure? - correct answers.Location: it is where the DCT makes contact with the afferent arteriole Structure: macula densa cells in the wall of the DCT and juxtaglomerular cells (modified smooth muscle cells) in the afferent arteriole wall. When cells of the renal tubules secrete the drug penicillin, is the drug being added to or removed from the bloodstream? - correct ted penicillin is removed from the blood Which part of the filtration membrane prevents red blood cells from entering the capsular space? - correct rular fenestrations If the urinary excretion rate of a drug such as penicillin is greater than the rate at which it is filtered at the glomerulus, how else is it getting into the urine? - correct secretion What is the major chemical difference between blood plasma and glomerular filtrate? - correct plasma: contains blood cells, platelets, most plasma proteins and nutrients. glomerular filtrate: contains nutrients but no formed elements and very few, if any, of the plasma proteins. Why is there much greater filtration through glomerular capillaries than through capillaries elsewhere in the body? - correct rular capillaries present a large surface area for filtration, are about 50 times leakier than capillaries in most other tissues due to their large fenestrations, and glomerular capillary blood pressure is high. Write the equation for the calculation of net filtration pressure (NFP) and explain the meaning of each term - correct answers.HPgc)-(HPcs+OPgc), outward pressures-inward pressures. What is the function of the tight junction between tubule cells? - correct answers.With its barrier function of epithelial, it has long been suspected that tight junctions may be selectively permeable to some ions, because the perm selectivity of the para cellular pathway is variable in different segments of the renal tubule. How does filtered glucose enter and leave a PCT cell? - correct answers.It enters via Na+ symporters located in the apical membrane and leaves through the basolateral membrane via facilitated diffusion. By what mechanism is water reabsorbed from tubular fluid? - correct answers.The proximal tubule cells are most active in re absorption. Most of the nutrients, 65% of the water and sodium ions, and the bulk of actively transported ions are reabsorbed in the PCT. How does Na+, K+. Cl- ions transported in a thick ascending limb of the loop of Henle? - correct answers.Active NaCl transport in the thick ascending limb is driven by the basolateral Na+-K+-ATPase pump. The activity of this transporter is higher in the thick ascending limb than in other nephron segments, indicating the importance of active Na+ re absorption at this site [1-3]. The Na+-K+-ATPase pump has two major effects on Na+ handling: it actively transports reabsorbed Na+ out of the cell and back into the systemic circulation via the peritubular capillaries; and it maintains a low cell Na+ concentration that allows luminal Na+ to continue to enter the cell down a concentration gradient. Which hormone stimulates re absorption and secretion by principal cells, and how does this hormone exert its effect? - correct answers.Aldosterone-stimulates the principal cells int he collecting ducts to reabsorb more Na+ and Cl- and secrete more K+ with the re absorption of Na+ and Cl-; when more Na+ and Cl- are reabsorbed, more water is reabsorbed resulting in increased blood volume and a return of blood pressure to normal. Besides ADH, which other hormones contribute to the regulation of water re absorption? - correct answers.Angiotensin II and aldosterone Which hormones are responsible for influencing the renal re absorption? - correct answers.Aldosterone and antidiuretic hormone Which portions of the renal tubule and collecting duct reabsorb more solutes than water to produce dilute urine? - correct ding loop of henle and entire collecting duct. Which solutes are the main contributors in the high osmolality of interstitial fluid in the renal medulla? - correct answers.Na+, K+ and urea In which segments of the nephron and collecting duct does secretion occur? - correct answers.Secretion occurs in the proximal convoluted tubule, the loop of henle, the last part of the distal convoluted tubule, and the collecting duct How may kidney function be evaluated? - correct urine test or blood test What chemical substances normally are present in urine? - correct answers.Is a sterile fluid composed mostly of water,nitrogen-containing waste, and electrolytes. Important nitrogenous waste include urea, uric acid, ammonia, and creatinine What is micturition? How does the micturition relax occur? - correct answers.-urination -center in PONS -distension of bladder walls initiates spnal reflexes that stim contraction of external urethral sphincters and inhibit the detrusor muscle and internal sphincter. What is the approximate volume of blood plasma in a lean 60-kg male? In a lean 60-kg female? - correct answers.Plasma volume equals body mass x percent of body mass that is body fluid x proportion of body fluid that is ECF x proportion of ECF that is plasma x a conversion factor (1 liter/kg). - For males, blood plasma volume = 60 kg x 0.60 x 1/3 x 0.20 x 1 liter/kg = 2.4 liters. - Female blood plasma volume is 2.2 liters. How does hyperventilation, vomiting, fever, and diuretics affect water loss or gain? - correct increase fluid loss Dehydration can be corrected to homeostasis by what mechanism; negative or positive feedback? - correct answers.Negative feedback is in operation because the result (an increase in fluid intake) is opposite to the initiating stimulus (dehydration). How does hyperaldosteronism (excessive aldosterone secretion) cause edema? - correct answers.An elevated aldosterone level promotes abnormally high renal re absorption of NaCl and water, which expands blood volume and increases blood pressure. Because of the increased blood pressure, more fluid filters out of capillaries and accumulates in the interstitial fluid, causing edema. Why do solutions used for oral re hydration therapy contain a small amount of table salt (NaCl)? - correct answers.If a solution used for oral re hydration therapy contains a small amount of salt, both the salt and water are absorbed in the gastrointestinal tract, blood volume increases without a decrease in osmolarity, and water intoxication does not occur. How does thirst help regulate water intake? - correct ered by decrease in plasma osmolality How do angiotensin II, aldosterone, atrial natriuretic peptide, and antidiuretic hormone regulate the volume and osmolality of body fluids? - correct ne in plasma volume, increase in plasma osmolality What are the major cation and the two major anions in ECF and ICF? - correct answers.In ECF, the major cation is sodium ion, and the major anions are chloride ion and bicarbonate ion .- In ICF, the major cation is potassium ion, and the major anions are proteins and organic phosphates (for example, ATP). What are the functions of electrolytes in the body? - correct mine chemical and physical reactions of fluids Know hypernatremia, hypochloremia, hyperkalemia, hypercalcemia, hyperphosphatemia, hypomagnesemia- cause and symptoms. - correct answers.Hypernatremia: excess sodium- dehydration- thirst, CNS dehydration --> confusion, lethargy Hypochloremia: excess chloride- dehydration, increased retention/intake, metabolic acidosis, hyperparathyroidism- no direct clinical symptoms, generally associated w/ cause, often related to pH abnormalities Hyperkalemia: excess potassium- renal failure, deficit of aldosterone, rapid intravenous infusion of KCl, burns/severe tissue injuries that cause K+ to leave cells- nausea, vomiting, diarrhea, brady cardia, cardiac arrhythmias, depression, skeletal muscle weakness, flaccid paralysis Hypercalcemia: excess calcium- hyperparathyroidism, excessive vitamin D, prolonged immobilization, renal disease, malignancy- decreased neuromuscular excitability leading to cardiac arrhythmias, skeletal muscle weakness, confusion, kidney stones, nausea, vomiting Hyperphosphaemia: excess phosphate- decreased urinary loss due to renal failure, hypoparathyroidism, major tissue trauma, increased intestinal absorption If you hold breath for 30 seconds, what is likely to happen to your blood pH? - correct answers.Holding your breath causes blood pH to decrease slightly as carbon dioxide and hydrogen ions accumulate in the blood. What would be the effects of a drug that blocks the activity of carbonic anhydrase? - correct answers.A carbonic anhydrase inhibitor reduces secretion of hydrogen ions into the urine and reduces reabsorption of sodium ions and bicarbonate ions into the blood. It has a diuretic effect and can cause acidosis (lowered pH of the blood) due to loss of bicarbonate ions in the urine. Mechanisms that maintain pH of body fluids? - correct r systems - bicarbonate - phosphate - protein respiratory and renal systems=- physiological buffering systems Alkalosis and acidosis; common causes and compensation mechanism? - correct osis/alkalemia: abnormally low hydrogen ion concentration in ECF