Practicing Success

Target Exam

CUET

Subject

Biology

Chapter

Excretory Products and their Elimination

Question:

Match column I with column II and select the correct option:

      Column I      Column II
a)  Ammonotelic    (i)  Mammals and many terrestrial amphibians
b)  Ureotelic (ii) Reptiles, birds and land snails
c)  Uricotelic (iii) Bony fishes and aquatic amphibians
Options:

A-(ii), B-(iii), C-(i).

A-(iii), B-(i), C-(ii).

A-(i), B-(iii), C-(ii).

A-(i), B-(ii), C-(iii).

Correct Answer:

A-(iii), B-(i), C-(ii).

Explanation:

The correct answer is Option (2) - A-(iii), B-(i), C-(ii).

The process of excreting ammonia is Ammonotelism. Many bony fishes, aquatic amphibians and aquatic insects are ammonotelic in nature. Ammonia, as it is readily soluble, is generally excreted by diffusion across body surfaces or through gill surfaces (in fish) as ammonium ions. Kidneys do not play any significant role in its removal.

Terrestrial adaptation necessitated the production of lesser toxic nitrogenous wastes like urea and uric acid for conservation of water. Mammals, many terrestrial amphibians and marine fishes mainly excrete urea and are called ureotelic animals. Ammonia produced by metabolism is converted into urea in the liver of these animals and released into the blood which is filtered and excreted out by the kidneys. Some amount of urea may be retained in the kidney matrix of some of these animals to maintain a desired osmolarity.

Reptiles, birds, land snails and insects excrete nitrogenous wastes as uric acid in the form of pellet or paste with a minimum loss of water and are called uricotelic animals.