Preparing for NEET Biology 2026? Practice Chapter 16 Excretory Products and their Elimination MCQs with answers and detailed explanations based completely on NCERT Biology Class 11. This chapter is very important for NEET because questions are frequently asked from nephron structure, urine formation, osmoregulation, ADH, GFR, and counter-current mechanism.
This chapter-wise NEET MCQ practice set helps students revise:
- Structure of nephron
- Glomerular filtration
- Tubular reabsorption
- Tubular secretion
- Counter-current mechanism
- Hormonal regulation of kidney function
- Hemodialysis
- Excretory organs in animals
Important NEET Questions – Excretory Products and their Elimination
Q1. Which segment of the nephron is responsible for the selective passage of urea into the medullary interstitium?
A. Collecting duct
B. Distal convoluted tubule
C. Bowman’s capsule
D. Proximal convoluted tubule
Answer: A. Collecting duct
Explanation:
The collecting duct helps maintain osmolarity in the kidney medulla by allowing selective passage of urea into the medullary interstitium. This contributes to the counter-current mechanism and helps in concentrating urine.
Q2. Which organ plays a major role in the excretion of urea in ureotelic animals?
A. Heart
B. Liver
C. Kidney
D. Skin
Answer: C. Kidney
Explanation:
Urea is produced in the liver through the urea cycle, but kidneys are mainly responsible for removing it from the body through urine.
Q3. What is the typical pH of human urine?
A. 7
B. 5.5
C. 6
D. 8
Answer: C. 6
Explanation:
Human urine is generally slightly acidic with an average pH close to 6. Diet, hydration, and metabolism can slightly change urine pH.
Q4. Which process in the nephron is responsible for the formation of urine by separating waste from blood?
A. Filtration
B. Diffusion
C. Osmosis
D. Active transport
Answer: A. Filtration
Explanation:
Glomerular filtration is the first step of urine formation. Blood gets filtered in the glomerulus and the filtrate enters Bowman’s capsule.
Q5. The counter-current mechanism helps in:
A. Increasing blood pressure
B. Concentrating urine
C. Reducing GFR
D. Producing glucose
Answer: B. Concentrating urine
Explanation:
The counter-current mechanism creates an osmotic gradient in the kidney medulla, allowing greater water reabsorption and formation of concentrated urine.
Q6. Which hormone increases water reabsorption in collecting ducts?
A. Insulin
B. Thyroxine
C. ADH
D. Glucagon
Answer: C. ADH
Explanation:
Antidiuretic hormone (ADH) increases the permeability of collecting ducts, resulting in more water reabsorption and reduced urine output.
Q7. What is the approximate glomerular filtration rate (GFR) in a healthy human?
A. 50 mL/min
B. 75 mL/min
C. 125 mL/min
D. 200 mL/min
Answer: C. 125 mL/min
Explanation:
A healthy human kidney filters approximately 125 mL of filtrate per minute, which equals nearly 180 litres per day.
Q8. Which part of the nephron is mainly responsible for maximum reabsorption?
A. Loop of Henle
B. Distal convoluted tubule
C. Bowman’s capsule
D. Proximal convoluted tubule
Answer: D. Proximal convoluted tubule
Explanation:
The proximal convoluted tubule (PCT) reabsorbs most of the water, glucose, amino acids, and salts from the filtrate.
Q9. Aldosterone mainly helps in:
A. Increasing glucose levels
B. Sodium reabsorption
C. Protein synthesis
D. Oxygen transport
Answer: B. Sodium reabsorption
Explanation:
Aldosterone increases sodium reabsorption and potassium secretion in distal tubules and collecting ducts, helping regulate electrolyte balance.
Q10. Which structure is involved in ultrafiltration?
A. Ureter
B. Renal pelvis
C. Glomerulus
D. Collecting duct
Answer: C. Glomerulus
Explanation:
Ultrafiltration occurs in the glomerulus where blood pressure filters water and small solutes into Bowman’s capsule.
NEET Important Points from NCERT
- Human kidneys contain nearly one million nephrons.
- Normal GFR in humans is approximately 125 mL/minute.
- ADH increases water reabsorption in collecting ducts.
- Aldosterone regulates sodium and potassium balance.
- Mammals are ureotelic animals.
- The proximal convoluted tubule performs maximum reabsorption.
- Counter-current mechanism helps in concentration of urine.
Why This Chapter is Important for NEET
Questions from Excretory Products and their Elimination are frequently asked in:
- NEET Biology
- NCERT line-based MCQs
- Assertion and Reason questions
- Human Physiology section
Students should especially focus on:
- Nephron diagram
- Urine formation
- Counter-current mechanism
- RAAS system
- Hormonal regulation
Start Full Interactive Chapter Test
The premium full-length chapter test includes:
- 100 NCERT-based MCQs
- Live score tracking
- Timer-based interface
- Negative marking
- Performance analysis
👉 Start Full Interactive Test Here:
https://neet-ncert-mcqs.blogspot.com/2026/02/chapter-16-excretory-products-and-their_02124776162.html
Frequently Asked Questions (FAQs)
Is Chapter 16 important for NEET?
Yes, Excretory Products and their Elimination is an important NCERT chapter with repeated NEET questions every year.
Which topic is most important from this chapter?
Counter-current mechanism, nephron structure, urine formation, and hormonal regulation are highly important for NEET.
Are these MCQs NCERT based?
Yes, these MCQs are prepared mainly from NCERT Biology Class 11.
Does the full test contain negative marking?
Yes, the premium interactive test follows NEET-style negative marking and timer support
