NCERT Class 11-Biology: Chapter –19 Excretory Products and Their Elimination Part 3

Get top class preparation for ISAT Class-5 right from your home: Get full length tests using official NTA interface: all topics with exact weightage, real exam experience, detailed analytics, comparison and rankings, & questions with full solutions.

Very Short Answer Type Questions

Question 1:

Where does the selective reabsorption of Glomerular filtrate take place?


The selective re-absorption of glomerular filtrate takes place in the distal convolute tubule (DCT) .It is a portion of the functional unit of kidney called nephron which lies between the loop of Henle and the collecting tubule. Once the filtrate passes through the ascending limb of Henle, it then enters the distal convoluted tubule (duct of the renal tubule present in the cortex of kidney) that selectively reabsorbs minerals like calcium, sodium, and chloride thus regulating the pH of urine by secreting H+ ions and absorbing bicarbonate ions.

Question 2:

What is the excretory product from kidneys of reptiles?


The excretory product from kidneys of reptiles is uric acid. Uric acid is a breakdown product of nitrogen, formed when protein is metabolized in the body. Uricotelic organisms excrete uric acid as a waste product.

Question 3:

What is the composition of sweat produced by sweat glands?


The composition of sweat produced by sweat glands is lactic acid, salt, minerals and urea. The minerals may contain sodium, potassium, calcium, magnesium, etc.

Sweat glands are small tubular structures that produce sweat.

Question 4:

Identify the glands that perform the excretory function in prawns.


The glands that perform the excretory function in prawns is the antennal glands or the green glands. It is a pair of large glands present in some crustaceans like prawns which have an excretory function and would usually open at bases of the large antennae.

Question 5:

What is the excretory structure in amoeba?


The excretory structure in amoeba is contractile vacuole. The function of the contractile vacuole is osmoregulation i.e. it regulates the water content of the cell. It excretes wastes out of the cell through the cell membrane via the process of diffusion.

Question 6:

The following abbreviations are used in the context of excretory functions, what do they stand for?

a. ANF

b. ADH

c. GFR

d. DCT


(a) Atrial Natriuretic Factor

(b) Anti Diuretic Hormone

(c) Glomerular Filtration Rate

(d) Distal Convoluted Tubule

Question 7:

Differentiate Glycosuria from Ketonuria.


The differences between glycosuria and Ketonuria are:

The differences between glycosuria and Ketonuria



(i) Presence of glucose in urine is called glycosuria.

(i) Presence of ketone bodies in urine is called Ketonuria

(ii) This situation occurs when the person suffers from diabetes mellitus

(ii) This situation occurs at the time of long-time fasting

Question 8:

What is the role of sebaceous glands?


Sebaceous glands secrete sebum which makes the skin and hair waterproof.

Question 9:

Name two actively transported substances in Glomerular filtrate.


Glucose, Amino acid

Question 10:

Mention any two metabolic disorders, which can be diagnosed by analysis of urine.


Diabetes, Jaundice

Question 11:

What are the main processes of urine formation?


The main processes of urine formation are as follows:

(a) Glomerular filtration

(b) Reabsorption

(c) Secretion