Question

What is coelenteron otherwise called as?
(a)Body cavity
(b)Coelom
(c)Gastrovascular cavity
(d)Spongocoel

Answer 1

Hint: Coelenteron is the primary cavity that performs the function of the intestine related to digestion and circulation. The inward and outward movement is carried out from the same pore i.e. having a single opening.

Complete answer:
Coelenteron is the gastrovascular cavity present in the Cnidarians having a single opening called the mouth. Due to the presence of coelenteron, cnidarians are also called coelenterate. The coelenteron is considered as a gastrovascular cavity because it is where both digestion and gas exchange between the organism's cells and water in the cavity takes place.

Additional Information: The cavity can be either one large chamber, several smaller chambers, or a branched network of canals. The single (mouth) opening is surrounded by tentacles. Cnidarians are carnivores. They use cnidocytes on the surface of their tentacles to release nematocysts for attacking and capturing their prey. The inactive prey can then be brought into the coelenteron by the mouth. In contrast, Medusae also have oral arms that help in capturing and ingesting prey. The mode of digestion is extracellular within the coelenteron. The endodermal lining of the coelenteron is called the gastrodermis that absorbs nutrients derived from the digestive process.
The large, central cavity of sponges is called spongocoel. It is the characteristic of Phylum Porifera. It aids in water transport.
So, the correct answer is ‘Gastrovascular cavity’.

Note: - Coelenteron is commonly known as a blind gut or blind sac.
- Coelenterates are acoelomate.
- Coelenterates have a special type of cells called cnidoblast cells for capturing food.