The Human Male Reproductive System: Introduction: In mammals, including humans, the male reproductive system is respons…

Class Amphibia: Class Amphibia is a group of cold-blooded vertebrates or chordates that includes frogs, toads, salam…

Phylum Nematoda: Nematodes (Gr. nematos, thread) or roundworm are among the most common animals on on the earth-some …

Phylum Porefera: Porefera (Latin, porus=pore + fera=to bear), also known as sponges, is a diverse group of aquatic anim…

Protozoa Phylum Protozoa  (Gr. proto=first + zoa=animals) group of single-celled, eukaryotic microorganisms that are n…

Phylum Nemertia: Nemertia , also known as  nemertines , is a phylum of soft-bodied, invertebrate animals commonly found…

Platyhelminthes: Platyhelminthes , commonly known as flatworms , is a phylum of parasitic or free-living organisms tha…