After reading this article you will learn about the section of different invertebrates. 1. Scypha (= Sycon) sp. (Sponge): A. Longitudinal section: (Fig. 38.1) 1. Presence of ostia, incurrent canals, prosopyles, radial canals, apopyles, ex-current canals, gastric oscula in the wall; spongocoel at the centre, and osculum at the tip. 2. Body wall made up of two layers of cells, [...]
In this article we will discuss about the spot identification of different animals. I. Protozoa: Balantidium sp.: (Fig. 36.1) 1. Unicellular animal. 2. Short cilia cover whole body. 3. Cytopharynx present. 4. Micro- and macronucleus present. 5. Contractile vacuoles two with radiating canals. Systematic position: Subkingdom — Protozoa Phylum — Ciliophora Class — Kinetofragminophorea Subclass — Vestibuliferia Order — Trichostomatida [...]
In this article we will discuss about the collection of plankton. I. Biotic Community: An aquatic microscopic biotic community is constituted by: (a) Pelagic forms suspended in water, localised mostly towards the surface, and (b) Benthonic or bottom dwellers attached to the bottom or submerged in mud. Collection of Plankton: Pelagic forms: A. Hand net: 1. The plankton is collected [...]