Question

Which combination of class and its description is correct?

Options

A
Osteichthyes-A bony endoskeleton and gills covered by operculum
B
Reptilia-Left aortic arch & internal fertilization
C
Nematoda-Triploblastic & acoelomates
D
Cephalopods-Dorsal nerve cord & bilateral symmetry

Explanation

Osteichthyes is the class that contains fish with bony endoskeletons and gill slits covered by an operculum.

Osteichthyes are a group of vertebrates that includes freshwater and marine fish with skeletal skeletons. Each has a bony operculum covering its gills, and its entire body is covered in a thin coating of overlapping bony scales.

Both left and right arches are found in the adult reptiles and amphibians. However, in adult mammals only the left arch is found while in adult birds only the right arch is found.

Most reptiles reproduce sexually and have internal fertilization.

Nematodes are round with a body cavity. They have one way guts with a mouth at one end and an anus at the other. They have a pseudocoelom that is lined on one side with mesoderm and on the other side with endoderm.

Cephalopods are characterized by bilateral symmetry, a protruding head, and a modification of the mollusk foot into a muscular hydrostat which forms arms or tentacles. The class contains two extant subclasses.Cephalopods share a basic central nervous system organization.