Lamarck coined the term Molluscus. PHYLUM MOLLUSCA (SOFT BODY) I. CHARACTERISTICS A. Soft body of Molluscs. Bilaterally symmetry, segmented worms. Home Search Pdf Classification > Cells Enzymes ... Phylum Nematodes Nematodes are worms, but unlike annelids their bodies are not divided into segments. Vertebrates share certain physical characteristics: They have backbones, an internal skeleton (endoskeleton) for muscle attachment and growth, and muscles. PDF | On Jan 1, 2016, Richard C. Brusca and others published Phylum Mollusca | Find, read and cite all the research you need on ResearchGate Some also serve as intermediate hosts for parasitic trematodes, and others (e.g., snails) can be major agricultural pests. • There are 8 known living classes of molluscs and new species are constantly being discovered. Estimates of the number of species alive today range from 50,000 to 130,000. Most mollusks have well-developed nervous systems with large brains and sense organs. Body Form: The body of molluscs is un-segmented with a distinct head, muscular foot and visceral hump. Nucleic Acids. Molluscs have soft bodies and this explains the name of the phylum. procrastination.ppt. Contains snails, slugs, octopus, squid, and the "shell fish" (clams, oysters,limpets, and scallops); second largest phylum (greater than 100,000 species) B. Class 11 Notes Download Pdf : 1 : Symmetry: Distribution of body parts around a : 2 : hypothetical axis. Class . The term Mollusca was first applied by Aristotle to cuttle fish. In this article we will discuss about the general characters and classification of Phylum Mollusca. Most mollusks are herbivores, carnivores or filter feeders Protection Run away, hide in shell, release ink, secrete poisonous or distasteful chemicals, sting, camouflage . Three major classes make up the phylum Mollusca. Geothermal. Phylum Mollusca : General Characteristics and Classification (L., mollis=soft) Second largest phylum in number ; first being arthropoda; Malacology : Study of Mollusca ; Conchology : Study of shell of Mollusca ; Most molluscs are marine, some freshwater, some terrestrial. Snails, slugs, sea slugs Snail Conch Slug Whelk Abalone 4. Class . Phylum Mollusca “Soft Body” • _____ Major Classes – _____ -- Tooth, tusk shell – _____ (_____) -- Clams, mussels, oysters Unit 11 - Phylum Mollusca – Guided Notes General Characteristics • Three body parts: o _____Æmuscular foot: _____ May be modified in squid and octopus The diversity of the phylum is shown by at least eight known classes (cover). The body is cylindrical or vase shaped with bristly outer surface. Cell Biology. Phylum Mollusca . Phylum Mollusca. Unregimented and covered with calcareous shell. The phylum Mollusca consists of over 100,000 marine, freshwater, and terrestrial species. Many, however, occur in fresh water and some even in damp soil. Animal Kingdom Classification System Class 11 Notes Download In PDF ☞ Class 12 Solved Question paper 2020 ☞ Class 10 Solved Question paper 2020. Most are familiar to you as food sources: oysters, clams, scallops, and yes, snails, squid and octopods. Vertebrate and Invertebrate Animal Structure Notes (6 ... Vertebrates comprise only one phylum of animals. Phylum Mollusca In: Atkinson LJ and Sink KJ (eds) Field Guide to the Ofshore Marine Invertebrates of South Africa, Malachite Marketing and Media, Pretoria, pp. chitons. They are fresh water bivalves of India. Class- Gastropoda - “stomach foot” Has one shell or none Ex. Phylum Mollusca. Phylum Mollusca. Gastropoda. major features of mollusks • Learn the external and internal anatomy of the clam and squid • Understand the major advantages and limitations of the exoskeletons of mollusks in relation to the hydrostatic skeletons of worms and the endoskeletons of vertebrates, which you will examine later in the semester Section 21.5 Figure 21.15 Key features Mollusks Are Soft and Unsegmented. Nerves & Synapses. True coelomates (schizocoelomates). These are solitary or colonial (usually). Explanation are given for understanding. This phylum can be segregated into seven classes: Aplacophora, Monoplacophora, Polyplacophora, Bivalvia, Gastropoda, Cephalopoda, and … The bodies are generally very soft and are covered by the hard exoskeleton.They can be found in terrestrial regions as well as in the depths of the seas.You will be amazed to know that the size of the molluscans can range from 20 metres to one millimetre, with a few microscopic animals too. • They are one of the most diverse phyla, second only to Arthropods (insects, crabs, shrimp, and others). Animal Kingdom Classification System Class 11 Notes Download Pdf. Lamellidense, commonly known as mussels, belong to phylum-Mollusca, class — Bivalvia, and subclass — Palaeoheterodonta. Class . Phylum Mollusca means “soft body” 100,000 species of mollusks often called “shellfish” basic body plan-have soft body divided into 4 major parts 1. head-contains mouth & sensory organs 2. foot-used for movement 3. visceral mass-contains internal organs 4. mantle-thin layer of tissue that covers visceral mass & protects organs; also, secretes calcium carbonate for shell Most of the shells found on the beaches of the modem world belong to mollusks and mollusks are probably the most abundant invertebrate animals in modern oceans. They are usually white, long and thin. More than 500,000 known species. Phylum Annelida is divided into four main classes, primarly on the basis of setae, parapodia, metameres and other morphological features. Phylum Mollusca . Phylum Mollusca 3 embryonic germ layers true coelom complete gut second largest phylum of animals, around 100,000 species mainly aquatic, but some terrestrial species . Respiration . Animal Kingdom Organ.