Classification of Non-Chordates
ION OF
CLASSIFICATION OF NON-CHORDATES UPTO CLASSES
WITH SALIENT FEATURES Vanramliana Pachhunga University College Aizawl, Mizoram
1. Phylum Porifera: From the Latin porus for pore and Ferre to bear, hence an animal with with pores. ~5000 species.
Characteristic features:- a) Multicellular; no true tissue; asymmetric; sessile b) spongin- protein fibers for structure; spicules for skeleton c) filter feeders using collar cells (choanocytes) & amoebocytes d) Water enters pores and exits osculum e) asexual reproduction - fragmentation f) sexual reproduction - hermaphroditic g) External fertilization – shed gametes in water
Classification
Phylum Porifera can be divided into four classes: a) Class Calcarea: They are characterized by the presence of spicules made of calcium carbonate. e.g. Sycon, Leucosolenia. b) Class Hexactinellida: They are characterized by the presence of spicules six-rayed spicules are made silica. Eg. Euplectella . c) Class Demospongiae: They are characterized by the presence of siliceous spicules , in some species by spongin fibres, and others have a mixture of spongin and spicules. Eg: Hippospongia communis and Spongia officinalis, d) Class Sclerospongiae: They are characterized by the presence of spicules constructed from calcium carbonate, silica and spongin. e.g. Sclerospongia sp.
2. PHYLUM COELENTERATA(Cnidaria):~ 9000 species
Characteristics features: a) Radial symmetry; true tissues; sessile and/or motile b) Cnidocytes - stinging barbs to capture prey c) Tentacles to bring prey into gastrovascular cavity d) Nervous system in the form of a nerve net e) Two body forms –Polyp – sessile with mouth dorsal –Medusa – motile with mouth ventral f) Asexual reproduction - budding g) Sexual reproduction - external fertilization
Classification
a) Class Hydrozoa: They may be solitary or colonial form. Cnidocytes present in
CLASSIFICATION OF NON-CHORDATES UPTO CLASSES
WITH SALIENT FEATURES Vanramliana Pachhunga University College Aizawl, Mizoram
1. Phylum Porifera: From the Latin porus for pore and Ferre to bear, hence an animal with with pores. ~5000 species.
Characteristic features:- a) Multicellular; no true tissue; asymmetric; sessile b) spongin- protein fibers for structure; spicules for skeleton c) filter feeders using collar cells (choanocytes) & amoebocytes d) Water enters pores and exits osculum e) asexual reproduction - fragmentation f) sexual reproduction - hermaphroditic g) External fertilization – shed gametes in water
Classification
Phylum Porifera can be divided into four classes: a) Class Calcarea: They are characterized by the presence of spicules made of calcium carbonate. e.g. Sycon, Leucosolenia. b) Class Hexactinellida: They are characterized by the presence of spicules six-rayed spicules are made silica. Eg. Euplectella . c) Class Demospongiae: They are characterized by the presence of siliceous spicules , in some species by spongin fibres, and others have a mixture of spongin and spicules. Eg: Hippospongia communis and Spongia officinalis, d) Class Sclerospongiae: They are characterized by the presence of spicules constructed from calcium carbonate, silica and spongin. e.g. Sclerospongia sp.
2. PHYLUM COELENTERATA(Cnidaria):~ 9000 species
Characteristics features: a) Radial symmetry; true tissues; sessile and/or motile b) Cnidocytes - stinging barbs to capture prey c) Tentacles to bring prey into gastrovascular cavity d) Nervous system in the form of a nerve net e) Two body forms –Polyp – sessile with mouth dorsal –Medusa – motile with mouth ventral f) Asexual reproduction - budding g) Sexual reproduction - external fertilization
Classification
a) Class Hydrozoa: They may be solitary or colonial form. Cnidocytes present in