Mollusca 251 class scaphopoda the appropriately named tusk shells are a distinctive group of molluscs found in association with soft and unconsolidated substrata into which they burrow. Ppt phylum mollusca powerpoint presentation free to. They are selective predators of microinvertebrates living within the sediment. Species representing each of these classes are included in this guide. Of the four most abundant classes of living molluscs, polyplacophora chitons or coatofmail shells, bivalvia bivalves, gastropoda slugs and snails and. A study of the type series of nautilus pompilius linnaeus, 1758 mollusca, cephalopoda, nautilida svetlana v. They are one of the most diverse phyla, second only to.
Biology, earth science, ecology, paleontology, evolutionary science standards. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience. Mollusks block 1 nabinger purpose this lesson is intended to introduce the phylum mollusca and to go over its general physical characteristics. Here is a commonly used classification for molluscs.
There are high and middle school versions of each lab activity. Theyll give your presentations a professional, memorable appearance the kind of sophisticated look that todays audiences expect. Classification can be great fun and not as utterly boring as it sometimes turns out to be. Phylum mollusca is divided into eight classes, all but one of which are extant. Solenogastres small wormlike molluscs that live symbiotically or feed upon cnidarians. Around 85,000 extant species of molluscs are recognized.
Mollusks have a dramatic variety of form, ranging from large predatory squids and octopus, some of which show a high degree of intelligence, to grazing forms with elaborately sculpted and colored shells. Aplacophora, monoplacophora, polyplacophora, bivalvia, gastropoda, cephalopoda, and scaphopoda. Mussels clams bivalvia two hinged lateral shells and a wedged shaped foot. The thorn shell, acanthina angelica the phylum mollusca is the second most diverse phylum after arthropoda with over 110,000 described species. Phylum mollusca mollis, soft over 90,000 living species 70,000 fossil species some are herbivorous grazers some are predaceous carnivores many are filter feeders some are parasites. These advanced marine molluscs are active carnivores. One way to understand the diversity of mollusks through time, is to discuss the major classes that make up most of the fossil record of the phylum. Phylum mollusca class cephalopoda subclass nautiloidea the phylum mollusca includes the familiar classes gastropoda snails, pelecypoda clams, oysters and scallops, and cephalopoda squids, octopuses, and the chambered nautilus. Wormlike marine burrowers class solenogastres250 sp. There are 8 known living classes of molluscs and new species are constantly being discovered.
Phyla mollusca and annelida no prep warm ups, bell ringers, or inserts for interactive notebooks. Aplacophora, monoplacophora, polyplacophora, bivalvia, gastropoda, cephalopoda, and. Worlds best powerpoint templates crystalgraphics offers more powerpoint templates than anyone else in the world, with over 4 million to choose from. These classes are distinguished by, among other criteria, the presence and types of shells they possess. Monoplacophorans are thought to be ancestral to several other molluscan classes.
The smallest bivalves are microscopic and the largest are 4 feet across. Examples clams, oysters, mussels, scallops, snails, slugs, squid, octopus, limpets. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on youtube. Phyla platyhelminthes, nematoda, mollusca and annelida lab procedure and data phylum platyhelminthes the flat worms the animals in this phylum are the first to have bilateral symmetry, therefore they are triploblastic.
Class gastropodaview the video and images of gastropods and aquarium snails and compare the relatives spiraling of the shells of different species. Phylum mollusca characteristics, classification and examples. These are the univalved classes monoplacophora, gastropoda, and cephalopoda, the bivalved class pelecypoda bivalvia, and the pseudobivalved class rostroconchia. Wormlike marine surface dwellers class polyplacophora950 sp. Its fun if you can understand the need for it and how its done. A few molluscs such as unio possess green glands which mimic the liver in vertebrates. Aplacophora the class of mollusks which are worm like primitive forms without shell and nephridia aplacophora foot if present is a fold that lies in pedal groove class with calcarious spicules in the cuticle is aplacophora. It will also be used to setup a comparison between the major classes gastropoda, bivalvia, cephalopoda, and polyplacophora and to introduce discussion about the role of the mollusks in the ecosystem.
The phylum mollusca has about 100,000 described species and potentially 100,000 species yet to be described strong et al. In addi tion to three familiar molluscan classes comprising the clams bivalvia, snails and slugs gastropoda, and squids and octopuses cephalopoda, five. Cephalopoda authors rob leslie1 and marek lipinski2 citation leslie rw and lipinski mr. Class bivalvia clams, mussels, oysters, scallops use gills for respiration and filter feeding shell is modified into a bivalved shell connected by muscles and ligaments no head reduced sensory organs, no radula foot can be modified for digging dorsal umbothe oldest part of the shell ridges show where mantle has laid down shell. There are six classes of which three are more prominent. Mollusks may be primitively segmented, but all but the monoplacophorans characteristically lack segmentation and have bodies that are to some degree spirally twisted e. Refer to the photographs of the three species of littorina in the mitzi image library. Phylum mollusca includes snails and slugs, oysters and clams. Mnemonic classes and subclasses of phylum mollusca in. Only the gastropods have entered the terrestrial habitat, and some families of snails and mussels are commensalistic. Phylum mollusca is a very diverse 85,000 species group of mostly marine species. Mollusca is comprised of approximately 200,000 described living species, making it one of the largest animal phyla, and consists of eight living classes that are predominantly marine, with gastropods and bivalves the only ones to have spread to freshwater. Freshwater molluscs are classified into gastropods snails and freshwater limpets and several groups of.
Phylum mollusca class cephalopoda subclass nautiloidea. Habitat fresh and marine water slugs and snails can be terrestrial. Look inside the bodies of various marine animals molluscs. Introduction to mollusca and the class gastropoda freshwater. Match animals and characteristics to correct molluscan class. Understand the taxonomic relationships and 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.
They are more complex than the pseudocoelomate animals in. Class polyplacophora better known as chitons or coatofmail shells, these. Gastropoda snails means belly foot largest and most successful class of molluscs unlike clams, snails and slugs have a distinct head with brain, sense organs ocelli, tentacles, chemoreceptors and mouth mouth with radulaelongated body with foot below for gliding. Nervous system of phylum mollusca biology discussion. One of the largest of all animal phyla 50 000 110 000 living species depending on who is counting 3 evolution. The name mollusca indicates one of their distinctive character.
Has a mantle that secretes a calcareous shell, covering the visceral mass. This class is represented in the fossil record by members who built a hard outer shell. The head has a radula and there are usually large, sophisticated eyes with an architecture similar to that found in vertebrates. There are currently seven classes of mollusc recognized aplacophora, monoplacophora, polyplacophora, bivalvia, gastropoda, scaphopoda, cephalopoda and nearly all species within these taxa reproduce sexually, a process that requires males to produce spermatozoa. They are one of the most diverse phyla, second only to arthropods insects, crabs, shrimp, and others. Major mollusk classes four major classes of mollusks. Snails slugs gastropoda usually have chambered shells. Molluscs are soft bodied animals, often with hard shells for protection. Phylum mollusca is classified into seven classes class. Of the five classes of mollusks, four listed below are fairly common, and the first three will be studied in the laboratory figure 1.
Mnemonic classes and subclasses of phylum mollusca in taxonomy. Phylum mollusca bigelow laboratory for ocean sciences. Body structure of phylum mollusca, class xi, biology. Class aplacophora includes wormlike animals with no shell and a rudimentary body structure. Gastropoda single shelled cowries, cones etc bivalvia two shelled like clams, mussels etc aplacophora solenogasters monoplacophora segmented limpets polyplacophora or amphineura as it was earlier called chitons scaphopoda tusk. Phylum mollusca is a very diverse 85,000 species group of mostly marine species, with a dramatic variety of form. Page 42 makalah paleontologi phylum mollusca gambar 3. The freshwater gastropoda of the nearctic is divided into two major.
Gastropoda meaning stomach foot and bivalvia referring to two valves or shells. Freshwater gastropods are abundant organisms with dominant roles in lake and stream ecosystems. Molluscs can be divided into ive principal classes, namely gastropoda, bivalvia, scaphopoda, polyplacophora and cephalopoda. Atkinson lj and sink kj eds field guide to the ofshore marine invertebrates of south africa, malachite marketing and media, pretoria, pp. Jan 08, 2018 mollusca taxonomy class caudofoveata150 sp. The number of fossil species is estimated between 60,000 and 100,000 additional species. These warm ups cover the characteristics of each phylum, the classes of each phylum, the mollusk and annelid body plan, the clam, the earthworm, and more.
Compared and contrasted to pseudocoelomate animals a. Zoology mollusks block 1 nabinger purpose this lesson is. Flattened with dorsal segmented shell class monoplacophora25 sp. Phylum mollusca class polyplacophoraview the video on chiton facts on bb.
Snail movement marine snails such as littorina littorea, l. Phylum mollusca mollis, soft over 90,000 living species 70,000 fossil species some are herbivorous grazers some are predaceous carnivores many are filter feeders some are parasites mostly marine but some terrestrial and freshwater. The mollusca is well represented in freshwaters by two. Classification of phylum mollusca biology libretexts. Generally, however, most molluscs have no internal skeleton, no. The phylum mollusca includes snails, slugs, clams, squids, and. Pdf mollusca characteristics feeding and digestion. They use the phylum mollusca to undersand three major macroevolutionary patterns. Flattened with dorsal complete shell class gastropoda35 000 sp. The proportion of undescribed species is very high. Mollusca is the secondlargest phylum of invertebrate animals after the arthropoda. Caudofoveata small wormlike molluscs that live buried head down in the sea floor. They possess osphradia to test the chemical nature of water.
Kelompok a 7, 2016 tanpa nama, tanpa tahun kingdom. Winner of the standing ovation award for best powerpoint templates from presentations magazine. They are like the pseudocoelomate animals in that 1. May21 phylum mollusca worksheet is due on sunday may 24 at the beginning of class. It exhibits gradual coming up of complexities from simple to complex which can be marshalled into one perspectivethe nervous coordination. Some grownups cant see magic ponies but children can explanation.
Cephalopoda are addressed in a separate section due to the large number of species and their importance as a ishery. The foot is modified to form a funnel and tentacles with suckers around the mouth. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Phylum contains the largest invertebrate, architeuthis dux, or the giant squid. Phylum mollusca class polyplacophora class gastropoda class bivalvia class cephalopoda chitons snails sea slugs nudibranchs clams squid octopus cuttlefish nautilus. However, the earliest molluscs probably arose in the precambrian, and nothing is known about what they were like. The mollusca is well represented in freshwaters by two classes of molluscs or mollusks, depending on your preference. Pdf introduction to mollusca and the class gastropoda. Prior to the description of the nervous system in different forms of molluscs a basic plan of the molluscan nervous system is to be. There is debate over separating them into two classes.
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