NCERT Solutions for Class 11 Biology Chapter 19 2025: Download PDF

NCERT Solutions for Class 11 Biology Chapter 19: Excretory Products and Their Elimination – is a valuable resource to help students score well in exams. Experts at Embibe have created these NCERT solutions after extensive research to provide authentic and accurate solutions for Class 11 students. According to the most recent CBSE syllabus 2024-25, the provided solutions will assist students in understanding the concepts in an easy and simple language.

NCERT Solutions for Class 11 Biology Chapter 19 will ensure that students build a strong foundation for topics to score well in various exams as well. A proper understanding of this chapter will help them score better in exams. Continue reading this article to understand the topics of this chapter in detail.

NCERT Solutions for Class 11 Biology Chapter 19: Topics

Finding the right books and solutions usually becomes daunting with the abundance of options available on the Internet. Before getting into the detailed NCERT solutions for 11th Biology chapter 19, let us have a look at the sections and sub-sections of this chapter:

NCERT Solutions for Class 11 Biology Chapter 19: Download PDF

Students can download the NCERT solutions for Class 11 Biology Chapter 19 from here, and students can download it and study it at their convenience:

Q.1. Define Glomerular Filtration Rate (GFR)
Solution: The Glomerular Filtration Rate (GFR) is referred to as the amount of filtrate produced by the kidneys per unit of time. It is measured to identify the efficiency of the kidneys. GFR in a healthy individual is 125 ml per min, which is 180 litres per day.

Q.2. What is the significance of juxta glomerular apparatus (JGA) in kidney function?
Solution: Juxtaglomerular apparatus (JGA) is a specialized structure in the nephron formed by the close association between the distal convoluted tubule (DCT) and afferent renal arteriole. These structures help in maintaining osmolarity in the extracellular fluid of the body.
Whenever extracellular solute concentration (specifically sodium ion) becomes low in the body, this condition is detected by the juxtaglomerular apparatus (JGA). After which juxtaglomerular cells present in afferent arteriole secrete renin, leading to the renin-angiotensin pathway’s activation.
In this pathway, inactive angiotensinogen is converted into angiotensin I and further into angiotensin II, which has the following functions in our body-

• Angiotensin II is a vasoconstrictor which increases the blood pressure in the glomerulus by constricting the blood vessels. This causes increases in the Glomerular filtration rate.
• It also increases the reabsorption of water and sodium ions from the glomerular filtrate into the blood to increase blood volume and reduce blood pressure in the body.
• Increases the synthesis of aldosterone, a hormone secreted from the adrenal gland that helps reabsorption sodium ions from kidneys’ nephrons. This also helps regulate blood pressure and maintain extracellular fluid’s osmolarity.

DOWNLOAD NCERT SOLUTIONS CLASS 11 BIOLOGY CHAPTER 19

NCERT Solutions for Class 11 Biology Chapter 19: Chapter Description

The human excretory system consists of a pair of kidneys, ureters, urinary bladder, and urethra. The functions of all these organs are explained in this chapter. Nitrogen-containing substances, ions, CO₂, water, etc., accumulate in the body and must be eliminated. The nature of nitrogenous wastes formed and their excretion vary among animals depending on the habitat (availability of water).

Protonephridia, nephridia, malpighian tubules, green glands, and the kidneys are the common excretory organs in animals. They not only eliminate nitrogenous wastes but also help in the maintenance of the ionic and acid-base balance of the body. All these topics will be discussed in Class 11 Biology chapter 19 – Excretory Products and their Elimination. This is a low-weightage chapter from which around 1-3 questions are asked every year.

CBSE Class 11 Biology Chapter 19: Important Questions

Some of the important questions from this chapter are as follows:

1 Mark Important Questions From Excretory Products and their Elimination

• In which part of nephron filtration takes place?
• What is the PH of urine?
• Name the three kinds of nitrogen excretion.
• What are podocytes?
• Name the excretory organ of cockroach.

2 Mark Important Questions From Excretory Products and their Elimination

• Differentiate between Rennin and Renin?
• What are the two intrinsic mechanisms that provide autoregulation of glomerular filtrate? Explain any one of these.
• Kidneys do not play a major role in excretion in ammonotelic animals. Justify.
• Define the glomerular filtration rate. What is its value in a healthy human?
• Name two metabolic disorders which can be diagnosed by the analysis of urine.

3 Mark Important Questions From Excretory Products and their Elimination

• Explain briefly how micturation is a reflex process but is also under some voluntary control.
• Describe the urea cycle.
• What is a dialysis machine? When is it needed?
• How does the liver act as both digestive as well as an excretory organ?

5 Mark Important Questions From Excretory Products and their Elimination

• Describe briefly the structure and function of the renal corpuscle.
• Describe the mechanism of urine formation.
• Describe the renal excretory system of man.

FAQs on NCERT Solutions Class 11 Biology Chapter 19 2024-25

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