Phylum Mollusca is the second largest invertebrate phylum containing more than 90000 described living species after phylum Arthropoda. Johnston has first coined the name Mollusca in 1650. Although Aristotle was probably the first person to recognize the mollusks. He divided…
In the phylum Arthropoda, there is the most number of animal species. The phylum Arthropoda contains more than 1079290 known species like Apis, Laccifer, Millipede, Palaemon, etc. The name Arthropoda is derived from the Greek words Arthron and podos. ”…
The phylum Annelida is a group of organisms having ring-shaped segments. The term Annelida is derived from the Latin word; ” Annulus = ring “ There are more than 15000 known species of this phylum. This phylum includes several subgroups…
Aschelminthes is considered a superphylum, which includes many phyla. The term Aschelminthes was first introduced by Grobben in 1910. Earlier in 1859, Gegenbour was named Nemathelminthes for this phylum. So, the Phylum Aschelminthes is also known as the phylum Nemathelminthis…
In 1859 the scientist Gegenbaur proposed the name phylum platyhelminthes. Originally the animals of this group were placed in the taxon vermis by Linnaeus in 1735 along with other worms. In 1876 Minot recognized Platyhelminthes as a separate phylum. The…
Phylum Ctenophora and Phylum Cnidaria were in one phylum (phylum Coelenterata) in the early days. Later Coelenterata was divided into two separate phyla one is Cnidaria and the other is Ctenophora. In the phylum Ctenophora, animals are bearing special forms…
Phylum Cnidaria is the group of multicellular animals belonging to the sub-kingdom of Enterozao. According to tissue differentiation, the animals of this group are two types diploblastic and triploblastic. In the early days, cnidarians and ctenophores would be considered the…
The scientist R. Grant used the term phylum-Porifera for the first time in 1836. Phylum-Porifera belongs to the sub-kingdom Parazoa. Although all the animals of Porifera are multicellular, the cells that make up the body do not form tissues and…
In 1822, the scientist Goldfuss first used the term protozoa. Protozoa are referred to as animals whose bodies are made up of a single cell. However, it represents a division of Protista and this division is difficult to be distinguished…
The respiratory gases are taken during normal breathing extend into two regions between the respiratory tract -i.e, the conducting zone and the respiratory zone. The wall of the respiratory transport zone is thick enough and not suitable for gas exchange,…