CBSE Questions for Class 11 Medical Biology Excretory Products And Their Elimination Quiz 1 - MCQExams.com

• The human body loses water by sweating, excretion, and breathing. Sweating, excretion, and breathing are the different excretory mechanisms of the body. 
• The body loses excess electrolytes and ions through sweat. The body loses nitrogenous wastes and excess electrolytes through urine. The body loses carbon dioxide and a little amount of water in the form of vapor through breathing.

Glycosuria is the excretion of glucose into the urine. It is caused due to the inhibition of glucose absorption during the process of tubular reabsorption in the kidneys or the excess of glucose in the blood due to untreated diabetes mellitus. The presence of glucose in the urine increases its osmotic pressure and thus more is absorbed into the urine and results in heavy water loss. It causes dehydration, a process called osmotic diuresis. 

So, the correct answer is option A. 

• The practical unit of the excretory organ is termed as the nephron. It includes a twisted renal tubule and a  shaped structure network of peritubular capillaries.
•  The tube-shaped structure consists of various regions, every with its own vital performance. Hence, the functional unit of the kidney is the Nephron.

• The peripheral region of the kidney is the cortical region and called cortex but the central is called the medulla.
• Malphagian corpuscle, convoluted tubules of a nephron are present in the cortical region.
• Blood in the glomerulus enters through the afferent arteriole and exits from the efferent arteriole.
• The cocave part of the kidney is called the hilus, from this the ureter and the renal vein exits from the kidney and renal artery enters the kidney.
• So, the (C) statement is not correct.

• Urine pH is of diagnostic importance. The kidneys maintain a normal acid-base balance primarily through the reabsorption of sodium and the tubular secretion of hydrogen and ammonium ions.
• Urine becomes increasingly acidic as the amount of sodium and excess acid retained by the body increases. The glomerular filtrate of blood is usually acidified by the kidneys from a pH of approximately 7.4 to a pH of about pH = 6.0 in the urine.
• So, the correct answer is option B.

• In our body DNA is broken down to purines which are further broken down to form uric acid.
• Uric acid is a chemical created when the body breaks down Purines in blood
• A high uric acid level is known as hyperuricemia. This can lead to a disease called gout that causes painful joints that accumulate urate crystals hence the body gets rid of uric acid when you urinate or have a bowel movement.
• Hence Uric acid forms in the body by DNA.
• So, the correct answer is 'DNA'.

$$\textbf{Correct option: }$$A

$$\textbf{ Solution: }$$

$$\textbf{ Option (A): }$$

$$\bullet$$The self regulatory process of the organism which tends to maintain stability and internal body temperature is known as homeostasis. 

$$\bullet$$The higher animals such as mammals tend to maintain a constant internal environment despite of the changes occurring in the external environment.