Question

Select the total number of correct matching. (1) JGA \(\rightarrow\) Juxtaglomerular Apparatus (2) GFR \(\rightarrow\) Glomerular Filtration Rate (3) \(\mathrm{PCT} \rightarrow\) Proximal Conducting Tube (4) DCT \(\rightarrow\) Distal Convoluted Tubule (5) \(\mathrm{CD} \rightarrow\) Conducting Duct (6) \(\mathrm{ADH} \rightarrow\) Antidiuretic Hormone (a) 6 (b) 5 (c) 4 (d) 2

Short answer

The total number of correct matches is four, therefore the answer is (c) 4

Step-by-step solution

Identifying Correct Matches

Firstly, go through each of the provided pairs and see if the acronym matches correctly with its full form. If necessary, conduct a quick research to validate. (1) JGA \(\rightarrow\) Juxtaglomerular Apparatus: Correct. (2) GFR \(\rightarrow\) Glomerular Filtration Rate: Correct. (3) \(\mathrm{PCT} \rightarrow\) Proximal Conducting Tube: Incorrect, it should be Proximal Convoluted Tubule. (4) DCT \(\rightarrow\) Distal Convoluted Tubule: Correct. (5) \(\mathrm{CD} \rightarrow\) Conducting Duct: Incorrect, it should be Collecting Duct. (6) \(\mathrm{ADH} \rightarrow\) Antidiuretic Hormone: Correct.

Counting Correct Matches

Secondly, count the number of correct matches from the list. The correct matches are: (1) JGA, (2) GFR, (4) DCT, and (6) ADH. So we have 4 correct matches.

Selecting the Correct Option

Finally, check the options and select the one that matches the total number of correct matches. In this case, the total number of correct matches is 4. So, the correct option is (c) 4.

Key concepts

Juxtaglomerular Apparatus

The juxtaglomerular apparatus (JGA) is a crucial part of the nephron, playing a key role in regulating blood pressure and the filtration rate of the glomerulus. It is located where the distal convoluted tubule comes into contact with the afferent arteriole of the glomerulus.
The primary function of the JGA is to monitor blood pressure and sodium concentration.

• Renin Secretion: When blood pressure is low, the JGA releases renin, an enzyme that helps increase blood pressure through the renin-angiotensin system.
• Feedback Mechanism: It helps adjust the glomerular filtration rate by sending signals that influence the constriction of arterioles.

This apparatus ensures that the nephron can adapt to changing physiological conditions.

Glomerular Filtration Rate

Glomerular filtration rate (GFR) measures how well your kidneys filter blood.
It's essential for understanding kidney health and function. Normal GFR varies by age, gender, and body size, but for most adults, a typical range is 90-120 mL/min/1.73 m².

• Filtration Process: Blood enters the glomerulus, where it's filtered to remove waste, excess substances, and fluids.
• Indicators of Kidney Health: GFR is used to identify potential kidney problems like chronic kidney disease.
• Factors Influencing GFR: Blood pressure, blood volume, and osmotic pressure are some factors affecting GFR.

Maintaining a proper GFR is vital for efficient kidney function.

Proximal Convoluted Tubule

The proximal convoluted tubule (PCT) is the first segment of the renal tubule and plays a major role in reabsorbing nutrients into the blood.
It is lined with cells rich in mitochondria, which provide energy for active transport processes.

• Reabsorption: Approximately 65% of filtered water and electrolytes are absorbed here, along with glucose, amino acids, and other nutrients.
• Secretion: Hydrogen ions and waste products are secreted into the tubular fluid.
• Selectivity: The PCT has specialized transporters for sodium, chloride, and other ions.

This tubule helps the nephron efficiently reclaim vital substances from the filtrate.

Distal Convoluted Tubule

The distal convoluted tubule (DCT) is the segment of the nephron after the loop of Henle, involved in the selective reabsorption and secretion processes.
It is under hormonal influence, particularly by aldosterone and ADH, which modulate its activity.

• Reabsorption: Sodium, calcium, and water are reabsorbed here, with the latter being influenced by ADH.
• Secretion: Potassium and hydrogen ions are secreted into the tubule.
• Acid-Base Balance: Plays a role in maintaining the pH balance in the blood.

The DCT is essential for fine-tuning the chemical composition of urine.

Antidiuretic Hormone

Antidiuretic hormone (ADH), also known as vasopressin, is a peptide hormone that helps regulate water balance in the body by acting on the kidneys.
It is produced in the hypothalamus and stored in the pituitary gland.

• Function: ADH increases the permeability of the nephron's collecting ducts, allowing more water to be reabsorbed into the bloodstream.
• Response to Dehydration: When the body is dehydrated, ADH levels rise, promoting water reabsorption and reducing urine output.
• Regulatory Role: Helps maintain blood pressure and volume by conserving water.

ADH is crucial for preventing water loss and managing fluid balance in the body.