\n| Aquatic insects<\/td>\n | Cartilage fishes<\/td>\n | <\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Question 2.
\nIn an informal discussion in your class, your friend made a comment that \u201cMalphigean tubules are the kidneys of a cockroach\u201d. How will you evaluate this statement?\u00a0(MARCH-2010)<\/span>
\nAnswer:
\nThe statement is correct. The kidney is the excretory organ of man and Malpighian tubules are the excretory organ of cockroach.<\/p>\nQuestion 3.
\nObserve the figure.\u00a0(MARCH-2011)<\/span>
\nNo need to redraw the figure.
\n![\"Plus](\"https:\/\/www.aplustopper.com\/wp-content\/uploads\/2019\/05\/Plus-One-Zoology-Chapter-Wise-Previous-Questions-Chapter-8-Excretory-Products-and-their-Elimination-1.png\")
\nLabel A and B and write the function of A and B.
\nAnswer:
\nA – Proximal convoluted Tubule (PCT)
\nB – Collecting duct.
\nFunctions:
\nA- Essential nutrients, 70-80% electrolytes and water are reabsorbed.
\nB- Reabsorption of water and urea to maintain os- molarity or secretion of H+ and K+ Ions.<\/p>\nQuestion 4.
\na) Prepare a flow chart of filtrate flow in the neph- rone using the following terms. (SAY-2011)<\/span>
\nCollecting duct, PCT, DCT, Ascending limb of Henle\u2019s loop, descending limb of Henle\u2019s loop, Bowman\u2019s capsule.
\nb) Counter current system plays an important role in concentrating urine. Name any two regions inside the kidney, where the counter current system is seen.
\nAnswer:
\n![\"Plus](\"https:\/\/www.aplustopper.com\/wp-content\/uploads\/2019\/05\/Plus-One-Zoology-Chapter-Wise-Previous-Questions-Chapter-8-Excretory-Products-and-their-Elimination-2.png\")
\nDescending limb of loop of Henle and ascending limb of loop of Henle.<\/p>\nQuestion 5.
\nComplete each of the following sentences using appropriate words.\u00a0(MARCH-2012)<\/span>
\na) Ascending limb of Henle\u2019s loop is ……….. to water whereas the descending limb is ……… to water.
\nb) An excessive loss of fluid from the body stimulates the hypothalamus to release ……… hormone from the …………
\nAnswer:
\na) Impermeable, Permeable
\nb) Antidiuretic hormone, Pituitary<\/p>\nQuestion 6.
\nIdentify the odd one and write the common feature of other items.\u00a0(SAY-2012)<\/span>
\nNephridia, Malpighian tubule, Spicules, Kidney, Flame cells.
\nAnswer:
\nSpicules – All other excretory organs.<\/p>\nQuestion 7.
\nHow does the countercurrent mechanism help to maintain the concentration gradient in the medullary interstitium?\u00a0(SAY-2012)<\/span>
\nAnswer:
\nMechanism of countercurrent in vasa recta or Henle\u2019s loop makes the difference in osmolarity in glomerular filtrate, blood and interstitium.<\/p>\nQuestion 8.
\nOn a hot day would you expect your level of ADH in blood to be high or low? Explain.\u00a0(SAY-2012)<\/span>
\nAnswer:
\nADH increases. It promotes reabsorption of water.<\/p>\nQuestion 9.
\nIn a Biology class related to excretion in the human body, a student gave an opinion that in every minute about 2% of the total blood volume of the body is converted to GFR whereas only 1% of this GFR is eliminated as urine. Evaluate this opinion and substantiate your answer.\u00a0(MARCH-2013)<\/span>
\nAnswer:
\nIn healthy individual the GFR is approximately 125 ml\/minute ie, 180 Ltrs. per day. It means that out of 5.5 Ltrs. of blood volume 1.5 Ltrs. per day urine is formed. This is due to re-absorption.<\/p>\nQuestion 10.
\nObserve the schematic diagram showing the mechanism for regulating blood volume.\u00a0(SAY-2013)<\/span>
\n![\"Plus](\"https:\/\/www.aplustopper.com\/wp-content\/uploads\/2019\/05\/Plus-One-Zoology-Chapter-Wise-Previous-Questions-Chapter-8-Excretory-Products-and-their-Elimination-3.png\")
\nFill the gap in the diagram.
\nIllustrate how blood volume is regulated by this system.
\nAnswer:
\na) Renin
\nb) A fall in glomemlar blood flow\/glomerular blood pressure\/GFR can activate the JG cells to release renin which converts angiotensinogen in blood to angiotensin I and further to angiotensin II. Angiotensin II increases the glomerular blood pressure and thereby GFR.<\/p>\nQuestion 11.
\nThe output of urine increases in cold days while de-creases in hot and sunny days. Can you give a rea-son for this phenomenon as realized from the graph given below?\u00a0(MARCH-2014)<\/span>
\n![\"Plus](\"https:\/\/www.aplustopper.com\/wp-content\/uploads\/2019\/05\/Plus-One-Zoology-Chapter-Wise-Previous-Questions-Chapter-8-Excretory-Products-and-their-Elimination-4.png\")
\nAnswer:
\nCold day – The release of low quantity of ADH de-creases tubular re-absorption of water and increases urine output.
\nHot day – The release of high quantity of ADH increases tubular re-absorption of water and decreases urine output.<\/p>\nQuestion 12.
\nA diagrammatic representation of a nephron is given.\u00a0(SAY-2014)<\/span>
\na) Identify the parts labelled as X and Y.
\nb) Which part\/parts of a nephron constitute the malpighian body?
\n![\"Plus](\"https:\/\/www.aplustopper.com\/wp-content\/uploads\/2019\/05\/Plus-One-Zoology-Chapter-Wise-Previous-Questions-Chapter-8-Excretory-Products-and-their-Elimination-5.png\")
\nAnswer:
\na) X-Bowmans capsule Y-collecting duct
\nb) Glomerulus along with Bowman\u2019s capsule is called the malpighian body or renal corpuscle<\/p>\nQuestion 13.
\nTerrestrial animals are either ureotelic or uricotelic not ammonotelic. Evaluate the statement.\u00a0(SAY-2015)<\/span>
\nAnswer:
\nMany terrestrial animals excrete either urea (ureotelic animals) or uric acid in the form of a pellet (urecotelic animals)<\/p>\nQuestion 14.
\n\u201cThe functioning of human kidney is efficiently monitored and regulated by hormonal actions of hypo-thalamus pituitory, JGA and to a certain extent by heart.\u201d\u00a0(MARCH-2016)<\/span>
\na) Do you agree with ,th is statement?
\nb) Justify your answerwith suitable reasons.
\nAnswer:
\na) yes
\nb) ADH It affect the kidney function by constricting effects on blood vessels – helps in water reabsorption
\nJGA is found in the distal convoluted tubule.A fall in GFR can activate the JG cells to release renin which can stimulate the glomerular blood flow.
\nANF – It can cause vasodilation (dilation of blood vessels) and thereby decrease the blood pressure.<\/p>\nQuestion 15.
\nUricotelism is more advantageous than ureotelism and ammonotelism in strictly terrestrial animals on the basis of water conservation in the body. Justify.\u00a0(SAY-2016)<\/span>
\nAnswer:
\nUric acid is the least toxic
\nIt is the terrestrial adaptation and minimum water loss occurs<\/p>\nQuestion 16.
\nPrepare two matching pairs from the given list of animals and excretory organs.\u00a0(MARCH-2017)<\/span><\/p>\n\n\n\nAnimals<\/strong><\/td>\nExcretory organs<\/strong><\/td>\n<\/tr>\n\n| a)\u00a0\u00a0\u00a0 Prawn<\/p>\n b)\u00a0\u00a0\u00a0 Cockroach<\/p>\n c)\u00a0\u00a0\u00a0 Earthworm<\/td>\n | i)\u00a0\u00a0\u00a0\u00a0 Nephridia<\/p>\n ii)\u00a0\u00a0\u00a0 Antennal gland<\/p>\n iii)\u00a0\u00a0\u00a0 Flame cells<\/p>\n iv)\u00a0\u00a0 Kidneys<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Answer:
\nPrawn – antennal gland
\nEarthworm – nephridia<\/p>\n | | | |