Phylum Mollusca- characteristics, classification, examples

Phylum Mollusca

Mollusca (Mollusks) Definition Molluscs (also know as mollusks) are soft-bodied, bilaterally symmetrical, segmented, coelomate animals; usually shelled having a mantle, ventral foot, anterior head, and a dorsal visceral mass. Phylum Mollusca (Mollusks) Characteristics They are essentially aquatic mostly marine, few freshwater and some terrestrial form. They may be found as hidden parasites in the interior … Read more Phylum Mollusca- characteristics, classification, examples

Phylum Nematoda- characteristics, classification, examples

Phylum Nematoda

Nematoda Definition Nematodes (Gr., nema thread+ eidos, form) are commonly referred to as non-segmented roundworm, threadworm or pinworm, as distinct from flatworm and higher segmented annelids. Image Source: Wikipedia Phylum Nematoda Characteristics They are widely distributed, aquatic or terrestrial, parasitic or free-living. Their body is elongated, cylindrical, unsegmented, worm-like, bilaterally symmetrical and tapering at both … Read more Phylum Nematoda- characteristics, classification, examples

Phylum Aschelminthes- characteristics, classification, examples

Phylum Aschelminthes

What are Aschelminthes? Aschelminthes are pseudocoelomate, bilaterally symmetrical, triploblastic, unsegmented, vermiform, organ- system grade of construction with complete digestive tubes. Phylum Aschelminthes characteristics They are mostly aquatic, free-living or parasitic. They are bilaterally symmetrical, unsegmented worms. The body is slender, vermiform and usually worm-like or flattened. They are usually small, even microscopic, while some reach … Read more Phylum Aschelminthes- characteristics, classification, examples

Phylum Platyhelminthes- characteristics, classification, examples

Phylum Platyhelminthes (flatworms)

Platyhelminthes (flatworms) definition Platyhelminthes are triploblastic, bilaterally symmetrical, dorsoventrally flattened, acoelomate flatworms with organ grade of construction without a definite anus, circulatory, skeletal or respiratory system but with Protonephridial excretory system and mesenchyme filling the space between the various organ of the body. Figure: Phylum Platyhelminthes. Source: WebMD and Wikipedia. Phylum Platyhelminthes (flatworms) characteristics They … Read more Phylum Platyhelminthes- characteristics, classification, examples

Phylum Annelida- characteristics, classification, examples

Diagram of Phylum Annelida

Annelida definition Annelids are defined as triploblastic, bilaterally symmetrical, metamerically segmented, a coelomate worm with a thin flexible cuticle around the body. Figure: Diagram of Phylum Annelida. Source: Wikipedia Phylum Annelida Characteristics They are mostly aquatic; marine or freshwater some terrestrial, burrowing or tubicolous, sedentary or free-living, some commensal and parasitic. The body is elongated, … Read more Phylum Annelida- characteristics, classification, examples

Protozoa- Definition, characteristics, classification, examples

General Characters of Phylum Protozoa

Protozoa Definition Protozoa may be defined asĀ  “microscopic acellular animalcules existing singly or in colonies, without tissue and organs, having one or more nuclei”. Some of the characteristics are: There are about 50,000 known species of Phylum Protozoa. Protozoans exhibit mainly two forms of life; free-living (aquatic, freshwater, seawater) and parasitic (ectoparasites or endoparasites). They … Read more Protozoa- Definition, characteristics, classification, examples