Question

Sponges are
A. Ammonotelic
B. Ureotelic
C. Uricotelic
D. Both B and C

Answer 1

Sponges are a type of aquatic organism with a porous exoskeleton. They have pores in their skeletons that aid in the exchange of materials between the organism's body and its surroundings.
Sponges are multicellular animals belonging to the Porifera phylum. They also have an osculum, which is a single big orifice. Osculum aids in the elimination of excretory waste. Ostia refers to the little pores. Nitrogenous wastes are formed as a consequence of protein metabolism in sponges.

Complete answer:
Option A: Ammonotelic organisms excrete ammonia, which is a nitrogenous waste product.
Ureotelic organisms excrete urea, which is a nitrogenous waste product.
Uricotelic organisms release uric acid, which is a nitrogenous waste product.
In sponges, excretion is primarily accomplished through diffusion across the body surface. Sponge excretion is primarily ammonia, making them ammonotelic.
So, option A is correct.
Option B: Ureotelic animals are those that excrete urea in the form of excrement. Urea is less toxic than ammonia, and its excretion requires less water.
So, option B is not correct.
Option C: Uricotelic organisms are animals that excrete uric acid in the form of faeces. In comparison to ammonia and urea, uric acid is the least toxic and the least water soluble.
So, option C is not correct.
Option D: Ammonia is a nitrogenous waste product excreted by ammonotelic organisms.
Urea, a nitrogenous waste product, is excreted by ureotelic organisms.
Uricotelic organisms produce uric acid, a nitrogen-based waste product.
Diffusion through the body surface is the primary mode of excretion in sponges. Sponge excrement is mostly ammonia; hence they're called ammonotelic.
So, option D is not correct.

So, option A is the correct answer.

Note:
The osculum is an excretory organ in sponges. After flowing through the spongocoel, water leaves via this hole to the outside. The excretory waste diffuses into the spongocoel's water and is sucked out from the osculum, eliminating the waste from the sponge's body. It's a wide hole that aids in the absorption and release of water. It's a critical part of the water-current system.