Question

Among coelomates, which of these develops by spiral cleavage and the mouth forms before the anus

Answer 1

Answer:

Protosomes

Explanation:

Protosome is a multicellular organism whose mouth grows before the anus from a primary embryonic opening which includesphyla mollusk, arthropod or annelid. Protosomes are developed by  spiral cleavage during embryo development.

Protosome animals have bilateral symmetry and three germ layers. Some of the examples of protostomes are snails and slugs (mollusk), earthworms (annelids), and spiders, lobsters, barnacles (arthropods).

Hence, the correct answer is Protosomes .