What are the steps that one would follow to classify an animal on the basis of the following fundamental features -Symmetry, Coelom, Circulatory system, Metamerism. answer only if u know
Answers
Explanation:
Annelida (L., annellus = little ring or F .anneler = to arrange in rings) are triploblastic, bilaterally symmetrical, coelomate and segmented Metazoa. Body is covered by a thin cuticle having chitinous setae in most. Body wall is covered with glandular epidermis, below which are muscles forming an outer layer of circular muscles and an inner layer of longitudinal muscles.
The body is divided for the first time in the animal series into metamerically arranged segments or metameres arranged in a linear series, but the segments are integrated into a single functional unit. Perivisceral cavity is a schizocoelic coelom between two layers of mesoderm. The coelom contains a coelomic fluid which is incompressible, consequently it acts as a hydraulic skeleton.
There is a single pre-oral segment called prostomium and a similar post-segmental region posteriorly known as a pygidium. The nervous system has a pair of pre-oral ganglia or brain, and paired ventral nerve cords ganglionated in each segment. There is a closed circulatory system.
The digestive tract is more or less straight but differentiated into well-defined regions; digestion is entirely extracellular. Organs of excretion are metameric ectodermal nephridia, besides which there are tubular mesodermal coelomoducts used for passage of reproductive cells. The larva, if present, is a trochosphere.
Answer:
symmetry and coelom dear
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