{"id":88614,"date":"2021-06-26T12:40:37","date_gmt":"2021-06-26T07:10:37","guid":{"rendered":"https:\/\/kseebsolutions.guru\/?p=88614"},"modified":"2021-07-02T09:23:27","modified_gmt":"2021-07-02T03:53:27","slug":"1st-puc-biology-question-bank-chapter-19","status":"publish","type":"post","link":"https:\/\/kseebsolutions.guru\/1st-puc-biology-question-bank-chapter-19\/","title":{"rendered":"1st PUC Biology Question Bank Chapter 19 Excretory Products and their Elimination"},"content":{"rendered":"

Karnataka 1st PUC Biology Question Bank Chapter 19\u00a0Excretory Products and their Elimination<\/h2>\n

1st PUC Biology Excretory Products and their Elimination One Marks Questions and Answers<\/h3>\n

Question 1.
\nWhich part of the nephron is concerned with selective tubular reabsorption?
\nAnswer:
\nRenal tubule (PCT, Henle\u2019s loop and DCT).<\/p>\n

\"1st<\/p>\n

Question 2.
\nWhat is glomerular nephritis?
\nAnswer:
\nGlomerular nephritis is the inflammation of kidneys caused by the bacterial infection.<\/p>\n

Question 3.
\nWhat is micturition?
\nAnswer:
\nThe process of elimination of urine from the urinary bladder is called micturition.<\/p>\n

Question 4.
\nWhat is dialysis?
\nAnswer:
\nDialysis is an artificial process of removing wastes from the blood to maintain the normal fluid and electrolyte balance.<\/p>\n

\"1st<\/p>\n

Question 5.
\nWhat is uraemia?
\nAnswer:
\nUraemia is a condition, where urea gets accumulated in the blood due to the failure of nephrons in the kidney.<\/p>\n

Question 6.
\nWhat is renal calculus?
\nAnswer:
\nCrystalline solids formed in the kidney due to the deposition of calcium oxalate; magnesium, ammonium phosphate and uric acid.<\/p>\n

Question 7.
\nWhat is renal failure?
\nAnswer:
\nRenal failure is the malfunctioning of uriniferous tubules of the kidney, which are unable to process the urine formation.<\/p>\n

Question 8.
\nDefine Glomerular Filtration Rate (GFR).
\nAnswer:
\nThe amount filtrate that flows out of all the nephrons of both the Kidney\u2019s over a period of one minute is called Glomerular filtration rate (GFR).<\/p>\n

\"1st<\/p>\n

Question 9.
\nWhat is the excretory product from kidneys of reptiles?
\nAnswer:
\nUric acid.<\/p>\n

Question 10.
\nIdentify the glands that perform the excretory function in prawns.
\nAnswer:
\nGreen glands (antennal glands).<\/p>\n

Question 11.
\nWhat is excretory structure or product in Amoeba?
\nAnswer:
\nAmmonia.<\/p>\n

1st PUC Biology Excretory Products and their Elimination Two Marks Questions and Answers<\/h3>\n

Question 1.
\nMention the symptoms for the presense of kidney stones.
\nAnswer:
\nThe symptoms for the presense of kidney stones are:
\na. While passing through ureter, they may cause damage.
\nb. They result in an intense pain in the lower abdomen called \u201cUreteric colic\u201d.
\nc. If the stones are large, they prevent the passage of urine (anuria).
\nd. A large stone causes in tense radiating pain, ulceration of the ureter and bleeding.<\/p>\n

\"1st<\/p>\n

Question 2.
\nMention the significance of dialysis.
\nAnswer:
\nThe significance of dialysis are,
\na. It helps in the removal of metabolic waste from blood by artificial methods.
\nb. Due to dialysis, the blood is purified by maintaining ionic balance.<\/p>\n

Question 3.
\nExplain the role of Henle\u2019s loop.
\nAnswer:
\nThe Henles loop helps in selective reabsorption. It absorbs ions like K+, Na+, HCO3 in preference to water.
\nIt helps in counter current multiplier system. In Henle\u2019s loop urine flows in the opposite direction.<\/p>\n

\"1st<\/p>\n

Question 4.
\nExplain ultra filtration.
\nAnswer:
\nBlood brought by the efferent arteriole is filtered in the glomerular capillaries because of the net effective pressure of 25mm of Hg. Net effective pressure is due to the differences in glomerular hydrostatic pressure, blood colloidal osmotic pressure and capsular hydrostatic pressure.
\nThis can be represented as,
\nGhp – (BCOP + CHP) = NEP
\ni.e., 75mm Hg – (30mm Hg + 20mm Hg) = 25mm Hg.<\/p>\n

During filtration, the blood cells and large organic molecules are retained in the capillaries. The fluid containing dissolved substances is passed into capsular lumen. This is called glomerular Filtrate. It contains a number of useful substances like glucose, aminoacids, mineral, etc., as well as waste products.<\/p>\n

Question 5.
\nDistinguish between acute renal failure and chronic renal failure.
\nAnswer:<\/p>\n\n\n\n\n
Acute renal failure<\/strong><\/td>\nChronic renal failure<\/strong><\/td>\n<\/tr>\n
1. It is the rapid malfunctioning of kidney.
\n2. It is caused due to the sudden Shock, myocardial failure, traumatic delivery, etc.,<\/td>\n		1.\u00a0\u00a0 It is the gradual malfunctioning of the kidney.
\n2.\u00a0\u00a0 It is caused due to nephritis, pyelonephritis uremia, glycosuria etc.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Question 6.
\nTerrestrial animals are generally either ureotelic or uricotelic, not ammonotelic, why?
\nAnswer:
\nTo conserve water.<\/p>\n

Question 7.
\nWhere does the selective reabsorption of glomerular filtrate take place?
\nAnswer:
\nProximal convoluted tubule, ascending limb of loop of Henle and distal convoluted tubule.<\/p>\n

\"1st<\/p>\n

Question 8.
\nWhat is the composition of sweat produced by sweat glands?
\nAnswer:
\nWater – 99.5% others like NaCl, Lactic acid, urea, amino acids and glucose 0.5% together.<\/p>\n

Question 9.
\nWhat is the role of sebaceous glands?
\nAnswer:
\nSebaceous glands produce oil or sebum for
\n(i) Lubrication of hair and skin
\n(ii) Excretion of waxes, sterols, oils and fatty acids.<\/p>\n

Question 10.
\nWhat are the main processes of urine formation?
\nAnswer:
\n(i) Ultrafiltration
\n(ii) Reabsorption
\n(iii) Secretion
\n(iv) Concentration – dilution.<\/p>\n

Question 11.
\nComplete the following:
\n(a) Urinary Excretion = Tubular reabsorption + Tubular secretion –
\n(b) Dialysis Fluid = Plasma –
\nAnswer:
\n(a) Urinary Excretion = Glomerular Filtration – Tubular reabsorption + Tubular secretion
\n(b) Dialysis Fluid = Plasma – Waste products.<\/p>\n

1st PUC Biology Excretory Products and their Elimination Three Marks Questions and Answers<\/h3>\n

Question 1.
\nShow the structure of a renal capsule with the help of a diagram.
\nAnswer:
\n\"1st<\/p>\n

Question 2.
\nLabel the parts in the diagram : Afferent arteriole, Efferent arteriole, Bowman\u2019s capsules, Glomerulus.
\nAnswer:
\n\"1st<\/p>\n

Question 3.
\nName the fallowing:
\n(a) A chordate animal having flame cells as excretory structures.
\n(b) Cortical portions projecting between the medullary pyramids in the human kidney.
\n(c) A loop of capillary running parallel to the Henle\u2019s loop.
\nAnswer:
\n(a) Ampbioxus.
\n(b) Columns of Bert in.
\n(c) Vasa recta.<\/p>\n

1st PUC Biology Excretory Products and their Elimination Five Marks Questions and Answers<\/h3>\n

Question 1.
\nDescribe the process of urine formation.
\nAnswer:
\nPhysiology of Urine formation :
\nThe process of urine formation involves three major steps.
\n1. Ultra filtration or Glomerular filtration.
\n2. Selective tubular re-absorption.
\n3. Tubular secretion or Augmentation.<\/p>\n

\"1st<\/p>\n

Ultra filtration :
\nIt takes place in the Glomerulus. During this process, blood along with waste materials enters into the glomerulus. The water in the plasma develops a pressure called Glomerular hydrostatic pressure (GHP – 60 mm Hg) and forces the plasma and other dissolved blood contents into the Bowman\u2019s capsule through the endothelial pores present on the wall of the afferent blood capillaries of the Glomerulus.<\/p>\n

Thus, water, Glucose, vitamins, amino acids, salts and Nitrogenous wastes such a urea are filtered into the Bowmen\u2019s capsule. After the filtration of all these substances, the pure blood flows away from the glomerulus through the efferent arteriole. The amount filtrate that flows out of all the nephrons of both the Kidney\u2019s over a period of one minute is called Glomerular filtration rate (GFR).<\/p>\n

The formed filtrate is called primary urine. It contains both essential and non-essential substances. Effective filtration pressure determines how much of filtration finally occurs.
\n\"1st<\/p>\n

Selective tubular re-absorption :
\nIt takes place in PCT. During this process the useful, and essential components of glomerular filtrate are re-absorbed back into the blood. Re-absorption takes place by both active, and passive transport. The sodium, potassium and glucose are re-absorbed by active transport (active absorption). When the sodium ions are more in the blood, the osmotic concentration of blood is greater than that of filtrate; hence water moves out of the tubule into the blood to re-establish osmotic concentration.<\/p>\n

Thus about 80% of water is re-absorbed by Henle\u2019s loop increasing the permeability of the cells (facultative water re-absorption). DOT also reabsorbs some amount of water from the primary urine. The reabsorption of water by kidney tubules is under the influence of anti-diuretic hormone (ADH).<\/p>\n

Tubular secretion or Augmentation :
\nIt is the final step in the formation of urine. It takes place in DCT. When the glomerular filtrate concentrated with wastes enters the DCT, the cells lining this segment secrete, and add some more wastes like hydrogen ions, ammonium ions, potassium ions, creatine, etc., into the filtrate which is already concentrated with wastes, in this stage, the fluid in DCT is called Urine. To maintain the normal blood pH (7.35 to 7.45) hydrogen, and ammonium ions will be secreted into the urine.
\n\"1st<\/p>\n

\"1st<\/p>\n

Question 2.
\nDescribe the structure of nephron with a neatly labelled diagram.
\nAnswer:
\nNephrons are highly coiled microscopic tubules. They are the structural and functional units of
\nkidney. Each nephroa has two distinct regions viz.
\n1. Bowman\u2019s capsule.
\n2. Tubule.
\n1. Bowman\u2019s Capsule : It is a spherical and double walled cup shaped sac like structure , found in the cortex region of the kidney. It possesses a lumen which is lined by a thin walled squamous epithelium. The capsular lumen is continous with tubular lumen.<\/p>\n

The capsule infolds anteriorly to receive afferent and efferent arterioles. Afferent arteriole gives off fine branches and forms a tuft of capillaries inside the Bowman\u2019s capsule which is called Glomerulus. Bowman\u2019s capsule with glomerulus is called Malphigian body or Malphigian corpuscle.<\/p>\n

\"1st<\/p>\n

2. Tubule : Tubule of a Nephron shows three distinct regions. They are:
\na. Proximal Convoluted Tubule (PCT).
\nb. Henle\u2019s Loop.
\nc. Distal Convoluted Tubule (DCT).
\na. Proximal Convoluted Tfibule: The proximal convoluted tubule is a coiled tube lying next to capsule. It is lined inside by cuboidal epithelium having microvilli. These microvilli form a brush border within a the lumen of PCT.<\/p>\n

b. Henle\u2019s Loop : The Henle\u2019s Loop is \u2018U\u2019 shaped fine tube with descending and ascending limbs. The lumen of the Henle\u2019s loop is lined by flattened epithelium, Henle\u2019s loop is found in the medulla region of the kidney.<\/p>\n

c. Distal Convoluted Tubule : The structure of distal convoluted tubule resembles with that of PCT. It is a also lined by cuboidal epithelium. However the cuboidal epithelium of the DCT shows indistinct brush border. The DCT opens into a collecting tubule which receives a number of nephrons.<\/p>\n

The efferent arteriole divides into a number of capillaries. These capillaries form a network all over the three regions of tubule and this network is called peritubular network.<\/p>\n

Question 3.
\nIndicate whether the following statements are true or false:
\n(a) Micturition is carried out by a reflex action.
\n(b) ADH helps in water elimination, making the urine hypotonic.
\n(c) Protein-free fluid is filtered from blood plasma into the Bowman\u2019s capsule.
\n(d) Henle\u2019s loop plays an important role in concentrating the urine.
\n(e) Glucose is actively reabsorbed in the proximal convoluted tubule.
\nAnswer:
\n(a) True
\n(b) False
\n(c) True
\n(d) True
\n(e) True.<\/p>\n

\"1st<\/p>\n

Question 4.
\nGive a brief account of the counter current mechanism.
\nAnswer:
\nCounter current multiplier system:
\nThe theory of counter current multiplier was proposed by Tirz and Bray. It explains the formation of concentrated urine. The system operates in the loop of Henle. Since the fluid flows in opposite direction of the descending and ascending limbs it is called counter-current. The mechanism is as follows:-<\/p>\n

\u2022 The descending limb is permeable to water and almost impermeable to solutes while the ascending limb is relatively impermeable to water but permeable to solutes.<\/p>\n

\u2022 The osmotic concentration down the renal pyramid increases from 290 milli osmoles per litre to 1400 mosm per litre.<\/p>\n

\u2022 As the intestitium is concentrated water diffuses out from the descending limb into intestitium until the fluids in the descending limb and intestitium are isotonic. This makes the filtrate increasingly hypertonic as it progresses towards the descending limb.<\/p>\n

\u2022 The ascending limb actively transports Na+ ion into the intestitial tissue. Thus the surrounding intestitium becomes concentrated.<\/p>\n

\u2022 The renal fluid gets progressively diluted as it passes up the ascending limb. The dilution is brought about by diffusion of Na+<\/sup> and Cl–<\/sup> ions from the filtrate to the outside. Hence the filtrate becomes hypotonic.<\/p>\n

\u2022 In the collecting duct water diffuses out and the filtrate becomes more concentrated to form urine. The diffusion of water from the collecting duct is controlled by ADH.<\/p>\n

\u2022 The urine then passes into the ureter through the pelvis. It is collected in the urinary bladder and removed from time to time.<\/p>\n

\"1st<\/p>\n

Urine : It is a light yellow coloured or amber coloured liquid. The colour of the urine is due to the presence of a pigment called urochrome, derived from the metabolism of bile Urine is composed of about 95-96% of water ,and 4-5% of solutes.<\/p>\n

Question 5.
\nExplain micturition.
\nAnswer:
\nMicturition
\nIt is the act of emptying of the urinary bladder or urination. As the urine accumulates in the urinary bladder the walls stretch. This is sensed by sensory receptors and transmitted to the brain to initiate the urge of urination.<\/p>\n

Role of other organs in the excretion of waste.<\/p>\n

    \n
  • Apart from kidneys, skin, lungs and liver are also involved in the elimination of waste substances.<\/li>\n
  • Sweat glands in the skin secrete sweat, which contains 99% water and traces of anti-bodies, lactic acid, urea, uric acid and ammonia.<\/li>\n
  • Lungs are involved in the excretion of carbondioxide.<\/li>\n
  • Liver helps in conversion of toxic ammonia into urea and also helps in detoxication of several ingested drugs.<\/li>\n<\/ul>\n

    \"1st<\/p>\n

    1st PUC Biology Excretory Products and their Elimination Text Book Questions and Answers<\/h3>\n

    The process of removal of metabolic nitrogenous waste products such as ammonia, urea and uric acid is known as excretion.<\/p>\n

    Based on the type of excretory product produced, animals are divided into 3 groups :
    \n1. Ammonotelic animals : Animals which excrete ammonia as nitrogenous waste product are called ammonotelic animals. e.g: Aquatic invertebrates and bony fish, larvae of frog (Tadpole).<\/p>\n

    2. Ureotelic animals : Animals which excrete urea are called ureotelic animals. Urea is produced by liver during ornithine cycle. Urea is stored in the urinary bladder in dissolved state called urine.
    \ne.g: Cartilaginous fish (Shark), Mammals and Amphibians.<\/p>\n

    3. Uricotelic animals : Animals which excrete uric acid as the nitrogenous waste product are called uricotelic animals. e.g: Reptiles, birds.<\/p>\n

    Excretory Organs :<\/p>\n

    1. Proto nephridia : It is the simplest tubular system present in platyhelminthes, some annelids and cephalochordates. It consists of a network of close, tubules and their branches. Ultimate branches terminate in flame cells. They are concerned with osmo regulation.<\/p>\n

    2. Nephridia : It is a tubular excretory organ of annelids with a ciliated furred shaped opening in the coelom called nephrostome. It is also responsible for osmo regulation.<\/p>\n

    3. Antennal Glands\/ Green Glands: These are the excretory organs in crustaceans and are located at the base of second antennules.<\/p>\n

    4. Malpighian tubules : These are thin, long and tubular excretory organs present in insects. They are present at the junction of midgut and hindgut and open into the alimentary canal. They also take part in osmo regulation.<\/p>\n

    \"1st<\/p>\n

    5. Kidneys : These are the excretory organs present in vertebrates. They are of two types namely, mesonephric and metanephric kidneys (advanced types and bean shaped). They contain structural and functional units called nephrons. They also take part in osmo regulation.<\/p>\n

    Human Excretory System :
    \nKidneys are the chief excretory organs of the human body. They are paired structures situated at the lower part of abdominal cavity attached to the dorsal body wall on either side of the vertebral column. They are bean seed shaped and reddish in colour.<\/p>\n

    For each kidney on their medial border, there is a depression called Hilum. It is the region at which the renal artery enters into the kidney, Renal vein and ureter exit. Each kidney is covered by a tough connective tissue membrane called Renal membrane.<\/p>\n

    The longitudinal section of the kidney reveals an outer cortex and an inner medulla. The cortex appears granular in nature. The medulla consists of triangular shaped structures called renal pyramids. Both cortex and Medulla are filled with a large number of microscopic tubules called Nephrons or Uriniferous tubules.<\/p>\n

    Structure of Nephron :
    \nEach Kidney contains millions of highly coiled tubules called Nephrons or Uriniferous tubules. Nephrons are the structural and functional units of the kidney :
    \nEach nephron consists of parts like malphigian corpuscle, convoluted tubules (PCT and DCT) Henle\u2019s loop and a collecting duct.<\/p>\n

    Malphigian corpuscle :
    \nIt includes Bowman\u2019s capsule and Glomerulus.<\/p>\n

    Bowman\u2019s Capsule :
    \nIt is a cup shaped structure composed of 2 layers. The outer layer is partial, and inner layer is known as visceral. The Bowmen\u2019s capsule is lined by a simple squamous epithelium. The epithelial cells have foot like processes called pedicel and such cells are called Podocytes. In between the podocytes, small pores called slit pores are present through which the glomerular filtrate enters into the proximal convoluted tubule.<\/p>\n

    Glomerulus :
    \nIt is a network of blood capillaries. It has 2 arterioles – Afferent (incoming) and Efferent (outgoing). The Endothelial wall of the blood capillaries are closely in touch with the squamous epithelium of Bowman\u2019s capsule. Glomerular filtration takes place in this region.<\/p>\n

    \"1st<\/p>\n

    Proximal convoluted tubule (PCT) :
    \nIt is highly coiled twisted tube. It is lined by a brush bordered cuboidal epithelial cells. Selective re absorption of essential substances takes place in PCT during urine formation.<\/p>\n

    Henle\u2019s loop :
    \nIt is a U-shaped tube with 3 parts – Descending, transverse, and ascending limbs. It is concerned with absorption of water during urine formation.<\/p>\n

    Distal convoluted tubule (DCT) :
    \nThe ascending limb of the Henle\u2019s loop is continued with DCT. It is lined by cuboidal epithelium. It is less coiled and broader than PCT. Active secretion of certain ions and water from blood takes place at this region. Collecting duct: It is a straight tube lined by columnar epithelium. Several collecting ducts open into the larger tubule which in turn opens into the pelvis of Kidney. It also reabsorbs water and Nations from the urine.<\/p>\n

    Physiology of Urine formation :
    \nThe process of urine formation involves three major steps.
    \n1. Ultra filtration or Glomerular filtration.
    \n2. Selective tubular re-absorption.
    \n3. Tubular secretion or Augmentation.<\/p>\n

    Ultra filtration :
    \nIt takes place in the Glomerulus. During this process, blood along with waste materials enters into the glomerulus. The water in the plasma develops a pressure called Glomerular hydrostatic pressure (GHP – 60 mm Hg) and forces the plasma and other dissolved blood contents into the Bowman\u2019s capsule through the endothelial pores present on the wall of the afferent blood capillaries of the Glomerulus.<\/p>\n

    Thus, water, Glucose, vitamins, amino acids, salts and Nitrogenous wastes such a urea are filtered into the Bowmen\u2019s capsule. After the filtration of all these substances, the pure blood flows away from the glomerulus through the efferent arteriole.<\/p>\n

    The amount filtrate that flows out of all the nephrons of both the Kidney\u2019s over a period of one minute is called Glomerular filtration rate (GFR). The formed filtrate is called primary urine. It contains both essential and non-essential substances. Effective filtration pressure determines how much of filtration finally occurs.
    \n\"1st<\/p>\n

    Selective tubular re-absorption :
    \nIt takes place in PCT. During this process the useful, and essential components of glomerular filtrate are
    \nre-absorbed back into the blood.<\/p>\n

    Re-absorption takes place by both active, and passive transport. The sodium, potassium and glucose are
    \nre-absorbed by active transport (active absorption). When the sodium ions are more in the blood, the osmotic concentration of blood is greater than that of filtrate; hence water moves out of the tubule into the blood to re-establish osmotic concentration. Thus about 80% of water is re-absorbed by Henle\u2019s loop increasing the permeability of the cells (facultative water re-absorption). DOT also reabsorbs some amount of water from the primary urine. The reabsorption of water by kidney tubules is under the influence of anti diuretic hormone (ADH).<\/p>\n

    \"1st<\/p>\n

    Tubular secretion or Augmentation :
    \nIt is the final step in the formation of urine. It takes place in DCT. When the glomerular filtrate concentrated with wastes enters the DCT, the cells lining this segment secrete, and add some more wastes like hydrogen ions, ammonium ions, potassium ions, creatine, etc., into the filtrate which is already concentrated with wastes, in this stage, the fluid in DCT is called Urine. To maintain the normal blood pH (7.35 to 7.45) hydrogen, and ammonium ions will be secreted into the urine.
    \n\"1st
    \nCounter current multiplier system:
    \nThe theory of counter current multiplier was proposed by Tirz and Bray. It explains the formation of concentrated urine. The system operates in the loop of Henle. Since the fluid flows in opposite direction of the descending and ascending limbs it is called counter-current.<\/p>\n

    The mechanism is as follows:-
    \n\u2022 The descending limb is permeable to water and almost impermeable to solutes while the ascending limb is relatively impermeable to water but permeable to solutes.<\/p>\n

    \u2022 The osmotic concentration down the renal pyramid increases from 290 milli osmoles per litre to 1400 mosm per litre.<\/p>\n

    \u2022 As the intestitium is concentrated water diffuses out from the descending limb into intestitium until the fluids in the descending limb and intestitium are isotonic. This makes the filtrate increasingly hypertonic as it progresses towards the descending limb.<\/p>\n

    \u2022 The ascending limb actively transports Na+ ion into the intestitial tissue. Thus the surrounding intestitium becomes concentrated.<\/p>\n

    \u2022 The renal fluid gets progressively diluted as it passes up the ascending limb. The dilution is brought about by diffusion of Na+ and Cl- ions from the filtrate to the outside. Hence the filtrate becomes hypotonic.<\/p>\n

    \u2022 In the collecting duct water diffuses out and the filtrate becomes more concentrated to form urine. The diffusion of water from the collecting duct is controlled by ADH.<\/p>\n

    \"1st<\/p>\n

    \u2022 The urine then passes into the ureter through the pelvis. It is collected in the urinary bladder and removed from time to time.<\/p>\n

    Urine : It is a light yellow coloured or amber coloured liquid. The colour of the urine is due to the presence of a pigment called urochrome, derived from the metabolism of bile Urine is composed of about 95-96% of water ,and 4-5% of solutes.<\/p>\n

    Composition of Urine :
    \nThe values given below are approximate % of urine composition.
    \n\"1st<\/p>\n

    The pH of urine is 6.5. The specific gravity of urine is 1.005 to 1.030.
    \nThe elimination of urine from the body is known is micturition or urination.<\/p>\n

    Functions of Kidney :
    \n1. It removes nitrogenous waste products such as ammonia, urea and uric acid.
    \n2. It regulates the water content in the body.
    \n3. It regulates the electrolytic balance in the body fluids such as sodium, potassium, chloride, etc.,
    \n4. It helps to maintain homeostasis in the tissue fluids.<\/p>\n

    \"1st<\/p>\n

    Regulation of kidney function:
    \nThere are three mechanisms to maintain normal functioning of kidneys. They are:
    \n1. Renal auto regulation – Renal auto regulation is the ability of the kidneys to maintain constant glomerular filtration rate in spite of changes in systemic arterial pressure.
    \n2. Hormonal regulation – Three hormones; angiotensil, atrial natriuretic peptide (ANP) and anti diuretic hormone (ADH) help in the regulation of the kidney function.
    \n3. Neural regulation – Autonomic nervous system controls the functions of kidney.<\/p>\n

    Micturition
    \nIt is the act of emptying of the urinary bladder or urination. As the urine accumulates in the urinary bladder the walls stretch. This is sensed by sensory receptors and transmitted to the brain to initiate the urge of urination.<\/p>\n

    Role of other organs in the excretion of waste.<\/p>\n

      \n
    • Apart from kidneys, skin, lungs and liver are also involved in the elimination of waste substances.<\/li>\n
    • Sweat glands in the skin secrete sweat, which contains 99% water and traces of anti-bodies, lactic acid, urea, uric acid and ammonia.<\/li>\n
    • Lungs are involved in the excretion of carbondioxide.<\/li>\n
    • Liver helps in conversion of toxic ammonia into urea and also helps in detoxication of several ingested drugs.<\/li>\n<\/ul>\n

      Disorders of Kidney :
      \n1. Kidney stones (Renal calculi)
      \nThe accumulation of salts and glycoproteins in the urinary tract (Kidney tubules) is known is Kidney stones. Kidney stones contain calcium oxalate salts.<\/p>\n

      \"1st<\/p>\n

      Causes :
      \n1. High level of calcium in the blood.
      \n2. Infection of the urinary tract.
      \n3. Tumors in the kidney.
      \n4. Less intake of water.
      \n5. Intake of more milk (when milk proteins are not adequately utilized by body cells and when it enters to Kidney tubules).
      \n6. Consumption of food which increases the alkalinity of the urine.<\/p>\n

      Effects :
      \n1. Severe pain it abdomen, pelvis and legs.
      \n2. Pain during Urination.
      \n3. Frequent urination with blood.
      \n4. Nausea and vomiting
      \n5. Severe pain in the Kidney region.<\/p>\n

      Treatment :
      \n1. It can be treated by passing LASER beam shock waves to pulverize the stones. This technique is called extra Corporeal Shock Wave Lithotripsy (ESWL).
      \n2. Endoscopic removal of stones.
      \n3. Surgical removal of stones.<\/p>\n

      2. Kidney Failure (Renal Failure):
      \nThe failure of Kidneys to perform ultra filtration, tubular re-absorption and tubular secretion is known is Kidney failure. There are 3 types of Kidney failures.
      \n(a) Acute Renal failure
      \n(b) Chronic Renal failure
      \n(c) End stage Renal failure.
      \nAcute Renal Failure (ARF) :
      \nIt is a sudden drastic loss of the function of both the Kidneys.<\/p>\n

      Causes :
      \n1. Physiological shock due to injury, excessive bleeding, hypotension, heart attack etc.
      \n2. Reduced blood supply to the Kidneys.
      \n3. Formation of renal calculi.
      \n4. Glomerule nephritis (infection to the Glomerulus by bacteria).
      \n5. Toxic chemicals.
      \n6. Drugs and alcohol.<\/p>\n

      \"1st<\/p>\n

      Symptoms :
      \n1. Uremia – Increased concentration of urea level in the blood.
      \n2. Oligouria Urine output is less than 250 ml per day.
      \n3. Aneuria – No urine output.
      \n4. Nausea and vomiting.
      \n5. Back Pain.
      \n6. Drowsiness and Headache.<\/p>\n

      Treatment :
      \n1. Drugs as prescribed by Urologist (Nephrologists).
      \n2. Dialysis<\/p>\n

      Chronic Renal Failure (CRF) :
      \nIt is a gradual, progressive and irreversible damage to the Kidney\u2019s resulting in decreased glomerular filtration rate (GFR).<\/p>\n

      Causes :
      \n1. Gtomerulo nephritis.
      \n2. Hypertension.
      \n3. Diabetes mellitus.
      \n4. Polycystic Kidney disease.
      \n5. Sickle cell anaemia.<\/p>\n

      \"1st<\/p>\n

      Symptoms :
      \n1. Decreased glomerular filtration rate.
      \n2. Weakness and loss of appetite.
      \n3. Frequent urination.
      \n4. Shortness in breathing.
      \n5. Nausea and vomiting.<\/p>\n

      Treatment :<\/p>\n