A)

(i) Sketch the excretory unit of a human kidney and label the following: Bowman’s capsule, Glomerulus, Collecting duct, and Renal artery.

(ii) Mention the important role of the structural and functional unit of the kidney.

(iii) Give any one function of an artificial kidney. 

 

                                                                       OR

B)

(a) What is excretion? 

(b) Which is the basic filtration unit present in the kidney? 

(c) Label the following organs of the excretory system which perform the following functions by drawing a labelled diagram of the excretory system in the human body. 

1.  Form urine. 
2.  is a long tube which collects urine from the kidney.  
3. Store urine until it is passed out.  

A)

(i)

(ii)“The structural and functional unit of the kidney is the nephron”. The important function of the nephron is filtration, reabsorption, secretion and urine formation. 

(iii) Artificial kidney helps in detoxification and removes extra salts and water, controlling blood pressure. The main function of an artificial kidney is to purify the blood. It also maintains the balance of sodium and potassium salts in a patient whose kidneys have failed.

                                                                       OR

B)

1. Excretion is the process through which animals get rid themselves of waste products and of the harmful nitrogenous by-products of metabolism. 
2. The simplest filtration unit present in the kidney is known as the nephron. Each kidney is made up of millions of filtering units called nephrons. The important function of the nephron is filtration, reabsorption, secretion and urine formation. 
3. Diagram of Human Excretory System.  

1.  Kidney: One of the functions of the kidney is to purify the blood and the filtrate obtained is the urine. 
2.  Ureter: The main work of ureters is to carry urine from the kidneys to the urinary bladder. 
3. Urinary Bladder: Urinary bladder is a temporary reservoir of urine. Urine is stored in the urinary bladder until it passes out through the ureter. 

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