Zoology paper IInd
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.
:- Respiration occurs through general body surface, in some cases by gills also.
:- Blood vascular system is closed type blood is red due to the presence of haemoglobin or erythrocruorin found dissolved in the plasma.
:- Excretion by segmentally arranged nephridia which is usually communicate the coelom to exterior.
:- Nervous system with a pair of cerebral ganglia the brain and a double nerve cord having segmentally arranged ganglia.
:- The tactile organs,taste buds, statocyst, photoreceptor cells and eyes are the receptor organs.
:- Usually monoecious,i.e., hermaphrodite;dioecious or unisexual forms also present.
:- Development direction monoecious forms but indirect in dioecious forms.
:- A free- swimming trochophore larval stage is characteristic in case of indirect development, while in others this stage is passed during the development.
:- Asexual reproduction Aldo occurs in some forms
It's all about the basic characteristicsGeneral --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.
:- Respiration occurs through general body surface, in some cases by gills also.
:- Blood vascular system is closed type blood is red due to the presence of haemoglobin or erythrocruorin found dissolved in the plasma.
:- Excretion by segmentally arranged nephridia which is usually communicate the coelom to exterior.
:- Nervous system with a pair of cerebral ganglia the brain and a double nerve cord having segmentally arranged ganglia.
:- The tactile organs,taste buds, statocyst, photoreceptor cells and eyes are the receptor organs.
:- Usually monoecious,i.e., hermaphrodite;dioecious or unisexual forms also present.
:- Development direction monoecious forms but indirect in dioecious forms.
:- A free- swimming trochophore larval stage is characteristic in case of indirect development, while in others this stage is passed during the development.
:- Asexual reproduction Aldo occurs in some forms
I'll bring about the classification
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Uncle ji super
ReplyDeleteNice bro...keep it up..😍
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