Shashank Mishra gonda

Class lllrd Hirudinea Hirudiy=a leech ) * >Mostly ectoparasitic and freshwater forms, while few are marine feeding upon fishes and other animals. >Body is elongated usually flattened dorsoventrally or cylindrical. >Body consist of definite number of segments each segment breaks up into 2 to 4 rings or annuli. >Parapodia and setae are absent. >Body is provided with an anterior and a posterior sucker, both situated ventrally . >Mouth opens on the ventral surface in the anterior sucker, while anus opens dorsal to the posterior sucker. >Hermaphrodite. >Asexual reproduction is not known. >Eggs are usually laid in cocoons* >Development is direct without free swimming larval stage. Class Hirudinea include three orders:- Order i.Acanthobdelid :- e.g. Acanthobdeilida Order ii.Rhynchobdellida:- e.g. pontobdella,Glossiphonia,Branchellion,piscicola. Order iii. Gnathobdellida:- Hirudo,Haemopis,Hirudinaria,Herpobdella.* *जोंक * Repr...

Class llnd. Oligochaeta Oligos=few,Chaeta=setae > Mostly terrestrial or some or some freshwater forms. >Body with conspicuous external and internal segmentation. >Distinct* head eyes and tentacles are absent. >Parapodia are absent*. >Setae are usually arranged segmentally. >Clitellum is usually present. >Phayrynx is not eversible without jaws*. >Hermaphrodite. >Development is directe and takes place within cocoons secreted by clitellum. Class Oligochaeta include two orders Order i.Archioligochaeta:-e.g. Tubifex,Aelosoma Order ii.Neo-oligochaeta:-e.g.Pheritima*,Eutypheus,Megaaacolex,Lumbricus. *Clear *Most important thing *झाबा *केंचुआ This all about the class llnd thanks for visiting my blog  if you want give me any suggestions please message me on my email or comments please And i am just comming with my new blog within some moments

-:Classification :- Phylum Annelida includes  four classes :- 1.Polychaeta 2.Oligocheta 3.Herudinea 4.Archiannelida Class lst:- Polychaeta:-. Poly- many   chaeta-bristles. >Polychaeta are marine and carnivorous -(मांसाहारी). > Body is elongated and segmented. >Head consists of prostomium and peristomium and bears eyes, tentacles,cirri and palps,etc. >Setae are numerous -(असंख्य)and are borne up on lateral* prominences* of the body wall known as Parapodia >Clitellum absent. >Cirri or branchia or both may be present forrespiration. >Coelom is spacious usually divided by inter-segmental septa. >Excretory organs are segmentally paired nephridia >Sexes are separate, fertilisation external,free swimming larval stage trochophore. > Asexual reproduction by lateral budding Class polychaeta include two orders:- Order i.:- Errantia: - e.g. Neris, Aphrodite,Glycera,Polynoe,Syllis. Order ii.:- Sedentaria:- e.g. Chaetopteru...

Zoology paper IInd  Phylum-- Annelida The name Annelida was first of all used by Lamarck in 1809 for the higher segmented worms(केंचुआ). General --characteristic Body Triploblastic , Bilaterally symmetrical , Elongated and Vermiform. :- Body metamericaly segmented ; externally by transverse grooves and internally by septa into a number of divisions; each division is called a segment metamere or somite Organ-system  grade of body organisation. :- Outer covering of the body is cuticle secreted by the underlying epidermis. :- Body wall is contractile consisting of an outer epidermis circular and longitudinal muscles . :- Appendages when present are un-jointed : - Locomotory organs are segmentally arranged paired setae or Chaetae in most of the case. :- Presence of a true schizocoelous coelom usually divided into a large number of compartments by inner-segmental septa. :- Alimentary canal is tube like complete extending from mouth to anus . :- Res...