Chapter 19: Excretory Products and Their Elimination – Case-Based / Source-Based Questions with Answers
CBSE Class 11 Biology Case-Based Questions – Excretory Products and Their Elimination (NCERT)
Course & Examination Details
- Course: CBSE Class 11 Biology
- Prescribed By: Central Board of Secondary Education
- Based On: NCERT
- Unit: Unit V – Human Physiology
- Chapter: Chapter 19 – Excretory Products and Their Elimination
- Question Type: Case-Based / Source-Based Questions
- Exam Relevance: CBSE Class 11 Annual Examination, Unit Tests, Competency-Based Assessments
Section A: Excretory System (Case 1–9)
Case 1
A student learns that accumulation of nitrogenous wastes can be toxic to the body.
Q1. Name the chief nitrogenous waste excreted by humans.
Answer:
Urea is the chief nitrogenous waste excreted by humans.
Q2. Why are humans called ureotelic organisms?
Answer:
Humans are ureotelic because they excrete nitrogenous waste mainly in the form of urea.
Case 2
A diagram of the human excretory system shows kidneys, ureters, urinary bladder, and urethra.
Q3. Name the main excretory organs in humans.
Answer:
Kidneys are the main excretory organs in humans.
Q4. State one function of ureters.
Answer:
Ureters transport urine from kidneys to the urinary bladder.
Case 3
A patient’s right kidney is located slightly lower than the left.
Q5. Give the reason for this position.
Answer:
The right kidney is lower due to the presence of the liver above it.
Case 4
During a dissection, a funnel-shaped structure leading to ureter is observed.
Q6. Name this structure.
Answer:
The structure is called the renal pelvis.
Case 5
Microscopic examination of kidney tissue reveals many small functional units.
Q7. Name the functional unit of kidney.
Answer:
The nephron is the functional unit of the kidney.
Case 6
Two types of nephrons are identified based on length of loop of Henle.
Q8. Which nephron type has long loops of Henle?
Answer:
Juxtamedullary nephrons have long loops of Henle.
Case 7
Blood enters and leaves the glomerulus through two different arterioles.
Q9. Name the arteriole that brings blood into the glomerulus.
Answer:
The afferent arteriole brings blood into the glomerulus.
Section B: Urine Formation (Case 10–18)
Case 8
A large volume of blood plasma is filtered daily by kidneys.
Q10. Name the process responsible for this filtration.
Answer:
Glomerular filtration is responsible for filtration of blood plasma.
Case 9
A student notes that proteins are absent in normal urine.
Q11. Why do proteins not appear in urine normally?
Answer:
Proteins are too large to pass through the glomerular filtration membrane.
Case 10
Maximum reabsorption of glucose and amino acids occurs in one nephron segment.
Q12. Name this segment.
Answer:
The proximal convoluted tubule is the main site of reabsorption.
Case 11
Certain ions are actively transferred from blood into the renal tubule.
Q13. Name this process.
Answer:
This process is called tubular secretion.
Case 12
A nephron segment helps establish an osmotic gradient in the medulla.
Q14. Identify this segment.
Answer:
The loop of Henle establishes the osmotic gradient.
Case 13
Urine becomes highly concentrated during water scarcity.
Q15. Which mechanism helps in urine concentration?
Answer:
The counter current mechanism helps in concentrating urine.
Case 14
Two structures work together as counter current systems.
Q16. Name these two structures.
Answer:
Loop of Henle and vasa recta act as counter current systems.
Case 15
A hormone increases water reabsorption in collecting ducts.
Q17. Name the hormone.
Answer:
Antidiuretic hormone (ADH) increases water reabsorption.
Case 16
A person produces dilute urine due to reduced ADH secretion.
Q18. What is this condition called?
Answer:
This condition is called diuresis.
Section C: Regulation of Kidney Function (Case 19–25)
Case 17
Blood pressure falls below normal in an individual.
Q19. Which kidney structure responds to this change?
Answer:
The juxtaglomerular apparatus responds to low blood pressure.
Case 18
A hormone released by JGA helps regulate blood pressure.
Q20. Name this hormone.
Answer:
Renin is released by the juxtaglomerular apparatus.
Case 19
Another hormone increases sodium reabsorption in kidneys.
Q21. Identify this hormone.
Answer:
Aldosterone increases sodium reabsorption.
Case 20
A hormone released from heart atria reduces blood volume.
Q22. Name this hormone.
Answer:
Atrial natriuretic factor (ANF) reduces blood volume.
Case 21
Urine stored in bladder is expelled by a reflex action.
Q23. Name this process.
Answer:
The process is called micturition.
Case 22
A patient suffers from accumulation of urea in blood.
Q24. Name this condition.
Answer:
The condition is called uremia.
Case 23
Kidneys fail to remove wastes effectively.
Q25. Name one artificial method used to remove wastes.
Answer:
Dialysis is used to remove wastes when kidneys fail.
NCERT & CBSE Compliance Note
✔ Strictly based on NCERT Class 11 Biology
✔ Competency-based and application-oriented
✔ Fully aligned with CBSE assessment pattern
✔ Ideal for board exams and internal assessments