Question

The distal convoluted tubule and collecting duct are important sites for?

1) active secretion of ions
2) active secretion of acids and other materials
3) selective reabsorption of sodium ions and water due to hormonal influence
4) secretion of creatinine, drugs and toxins
5) All the above statements are correct

Answer 1

The distal convoluted tubule and collecting duct in the kidney serve important roles in active secretion of ions, selective reabsorption of sodium ions and water, and secretion of creatinine, drugs, and toxins.

Step-by-step explanation:

The distal convoluted tubule and collecting duct in the kidney are important sites for several functions:

1. Active secretion of ions: The distal convoluted tubule and collecting duct can actively secrete ions such as potassium (K+) and hydrogen (H+) ions into the urine to help maintain pH and electrolyte balance in the blood.
2. Selective reabsorption of sodium ions and water due to hormonal influence: Hormones like aldosterone can influence the reabsorption of sodium ions (Na+) and water in the DCT and collecting duct, aiding in the regulation of blood volume and blood pressure.
3. Secretion of creatinine, drugs, and toxins: The DCT and collecting duct can also secrete substances like creatinine (a waste product of muscle metabolism), drugs, and toxins into the urine, contributing to the elimination of these substances from the body.

Therefore, the correct answer is option 5) All of the above statements are correct.