Kingdom Animalia 3 BFT 1023 Chapter 9 By Dr. Md. Shafiqur RahmanFaculty of Agro Industry and Natural resources UMK
Characteristics of Echinodermata1)Possess 5-rayed symmetry, mostlyradial, sometimes bilateral.2)Body has more than two cell layers, tissuesand organs.3)Body cavity a true coelom.4)Most possesses a through gut with an anus.5)Body shape highly variable, but with no head.6)Nervous system includes a circum-oesophageal ring.7)Has a poorly defined open circulatory system.
EchinodermataEchinoderms are characterized by radial symmetry, several arms (5 or more, mostly grouped 2 left - 1 middle - 2 right) radiating from a central body (= pentamerous). The body actually consists of five equal segments, each containing a duplicate set of various internal organs.
EchinodermataThey have no heart, brain, nor eyes, but some brittle stars seem to have light sensitive parts on their arms. Their mouth is situated on the underside and their anus on top (except feather stars, sea cucumbers and some urchins).
EchinodermataEchinoderms have tentacle-like structures called tube feet with suction pads situated at their extremities. These tube feet are hydraulically controlled by a remarkable vascular system.
EchinodermataThis system supplies water through canals of small muscular tubes to the tube feet. As the tube feet press against a moving object, water is withdrawn from them, resulting in a suction effect. When water returns to the canals, suction is released. The resulting locomotion is generally very slow.
Ecology and range of EchinodermsEchinoderms are exclusively marine. They occur in various habitats from the intertidal zone down to the bottom of the deep sea trenches and from sand to rubble to coral reefs and in cold and tropical seas.
Behavior of EchinodermsSome echinoderms are carnivorous (for example starfish) others are detritus foragers (for example some sea cucumbers) or planktonic feeders (for example basket stars).
Echinodermata8)Possesses a water vascular system, whichhydraulically operates the tube feet or feedingtentacles.9)Without excretory organs.10)Normally possesses a sub epidermal systemof calcareous plates11)Reproduction normally sexual andgonochoristic.12)Feeds on fine particles in the water, detritusor other animals.13)All live marine environments.
EchinodermataThe Echinodermata are Spiny-skinned animals such as Feather Stars, Starfish, Sea Urchins, Brittle Stars, Sea Cucumbers, Sand Dollars and Sea Lilies.
EchinodermataThey are one of the best known and most loved groups of invertebrates. They are popular as symbols because of their unique shapes and beautiful colours. They are also one of the most evolutionarily advanced phyla, yet they are totally unique in many ways.
Class AsteroideaStarfish, or Sea Stars are often a pest of commercial clam and oyster beds, a single Starfish my eat over a dozen oysters or young clams every day. The now infamous Crown- of-Thorns Starfish (Acanthaster planci) has caused serious damage to many coral reefs around the world, e.g. Asterias, Pisaster, Astropecten.
Adult Sea Star
Common Sea Star
Class OphiuroideaBrittle stars, star shaped echinoderms with arms distinct from the central disc; tube feet absent or reduced to censory organs. There are about 2000 species. e.g. Ophioderma (brittle star), Gorgonocephalus (Pacific basket star)
Giant Green Brittle Star
Giant Brittle Star Ophiocomina nigra
Basket StarBasket Star (GorgonocephalusCaputomedusae)
Class EchinoideaSea urchins, heart urchins, and sand dollars. Echinoderms with a rigid test of focused skeletal plates. Body covered with movable spines. Five rows of the tube feet (bearing sucker) around the test. About 950 species.
Heart UrchinThe common heart urchin
Sand dollarA sand dollar digging into the sand on the Playa Novillerobeach at low tide on the pacific coast of Mexico
Class CrinoideaSea Lilies, basket stars. Flower like echinoderms with a central calyx and five (or multiples of five) branching arms. Some species attach to the sea bottom by a stalk. About 625 species. e.g. Cerocrinus (crinoid).
Class Crinoidea Sea Lilies
Class Crinoidea Basket star
Class HolothuroideaSea Cucumbers. Non sessile soft bodied animals having a flexible body wall with many tiny, embeded calcareous ossicles; no spines or arms. Body elongated in the oral- aboral axis to a cucumber pickle like form. About 1200 species. e.g. Thyone, cucumaria.
Class Holothuroidea Sea Cucumber
Class Holothuroidea Sea cucumber
BiologyThe body wall of echinoderms consists of three layers. The outer layer, called the epidermis, is only a single layer of cells which covers the entire animal including its various spines. The third layer is also a single layer of cells the main difference being that these cells are ciliated. This layer encloses the the animals coelom separating the animals guts from its skin. It is called the coelomic lining
EchinodermataThe middle layer is much thicker and is called the dermis. It is composed of connective tissue and contains the exoskeleton
Reproduction and life cycleEchinoderms are fairly advanced invertebrates. This is evident in their embryology, which is similar to that of the vertebrates. Most species of echinoderms are diecious, meaning there are separate male and female individuals.
Reproduction and life cycleAlthough reproduction is usually sexual, involving fertilization of eggs by spermatozoa, several species of echinoderms, such as sea stars and sea cucumbers, can also reproduce asexually.
Reproduction and life cycleAsexual reproduction in echinoderms usually involves the division of the body into two or more parts and the reproduction of missing body parts.
Reproduction and life cycleSuccessful fission and regeneration require a body wall that can be torn and an ability to seal resultant wounds. Successful regeneration also requires that certain body parts be present in the lost pieces. For example, many sea stars can regenerate a lost portion only if some part of the central disk is present.
Sexual reproductionSexual reproduction involves the external fertilization of eggs by spermatozoa. The fertilized eggs develop into planktonic larvae. The larvae typically go through two stages, called bipinnaria and brachiolaria.
Sexual reproductionThey are bilaterally symmetrical and have bands of cilia used in swimming and feeding. As the larvae gradually metamorphose into adults, a complex reorganization and degeneration of internal organs occurs.
Sexual reproductionThe left side of the larva becomes the oral surface of the adult, which faces down, and the right side becomes the aboral surface, which faces up. The larvae settle to the sea floor and adopt their distinctive adult radial symmetry.
Classification1) Class: Asteroidea--Starfish or Sea Stars (Six- rayed Starfish--Leptasterias hexactis)--sea stars have fairly developed senses of smell, touch, and taste. They also can respond to the presence of light. They normally eat small prey whole, but they have to extrude their stomachs to digest larger prey outside their bodies.
The common starfish
The common Starfish
(2) Class: Ophiuroidea--Brittle Stars (Daisy Brittle Star--Ophiopholis aculeata) Another picture of a Brittle Star -found in all oceans (but mainly in the tropics). The group includes about 2000 species, varying in color. They eat decaying matter and microscopic organisms that are found on soft muddy bottoms.
(3) Class: Echinoidea- Sea Urchins-they locomote using short to long, movable spines. Between their spines are small, pincerlike organs called pedicellariae which they use to clean and defend themselves. The pedicellariae also contain a powerful toxin.
Phylum ChordataAll chordates have a dorsal hollownerve tube, a notochord, andpharyngeal gill slits. All vertebrates(members of a subphylum of chordata)have a backbone (spinal column) and aclosed circulatory system.
All chordates have the following characteristics at some point in their lives :1. The notochord is an elongate, rod-like, skeletal structure dorsal to the gut tube and ventral to the nerve cord. The notochord should not be confused with the backbone or vertebral column of most adult vertebrates
The notochord appears early in embryogeny and plays an important role in promoting or organizing the embryonic development of nearby structures. In most adult chordates the notochord disappears or becomes highly modified
The nerve cord of chordates develops dorsallyin the body as a hollow tube above thenotochord. In most species it differentiates inembryogeny into the brain anteriorly andspinal cord that runs through the trunk andtail. Together the brain and spinal cord arethe central nervous system to whichperipheral sensory and motor nervesconnect.
The visceral (also called pharyngeal or gill) clefts and arches are located in the pharyngeal part of the digestive tract behind the oral cavity and anterior to the esophagus. The ventral wall of the pharynx which produces mucus to gather food particles.
Chordates are well represented in marine, freshwater and terrestrial habitats from the Equator to the high northern and southern latitudes. The oldest fossil chordates are of Cambrian age
The smallest chordates (e.g. some of the tunicates and gobioid fishes) are mature at a length of about 1 cm, whereas the largest animals that have ever existed are chordates: some sauropod dinosaurs reached more than 20 m and living blue whales grow to about 30 m.
• Classification:• Kingdom: Animalia• Phylum: Chordata The Phylum Chordata contains the following subgroups: – Subphylum: Tunicata (tunicates) – Subphylum: Cephalochordata (lancelets) – Subphylum: Vertebrata (vertebrates)
ClassificationSubphylum Tunicata (Tunicates or Sea squirts)Animals with a well developed notochord and dorsal nerve cord in the free- swimming larva; specializes adults; sessile or planktonic, and lacking a notochord and dorsal nerve cord.e.g. Molgula (sea grape)
Sea Squirt (Polycarpa), Tunicates
Sea Squirts (Tunicates)
Sub phylum Cephalochordata (Lancelets)Elongate, fishlike chordates with a persistent notochord and dorsal nerve cord.e.g. Branchio-stoma (Amphioxus).
Class Agnatha: Members of the class Agnatha are jawless fish. Examples include lampreys and hagMembers of the Class Chondrichthyes have skeletons made of cartilage, placoid scales, and lack gill covers. Examples include sharks and rays. fish.
Classification of vertebrates VertebratesFish Amphibians Reptiles Birds Mammals Next
Fish (Live in water) • Lay eggs in water • Cold - blooded FinStreamlinedbody GillBack Slimy scales ! More...
Characteristic of fishFish are aquatic vertebrates that havevertebral column called spine. A classic fishis a torpedo shaped. The fish contains headcontaining a brain and sensory organs, atrunk with a muscular wall surrounding acavity with the internal organs and amuscular post-anal tail. The following arethe general characteristic that all the fishspecies posses:
Amphibians (Live both on land and in water) Breathe Wet, slimy skins with and no scales lung • Lay eggs in water • Cold - blooded Four limbsBack
Amphibians are cold-blooded animals,meaning they do not have a constantbody temperature but instead take onthe temperature of their environment.They have moist, scaleless skin thatabsorbs water and oxygen, but thatalso makes them vulnerable todehydration (loss of bodily fluids).
Reptiles Breathe with lung • Lay eggs on land • Cold - blooded Hard dry scalesBack
Reptiles are cold-blooded animals withscales covering their skin. Most of themare tetrapods, with four legs or leg-likeappendages. It is believed that reptilesstarted evolving around 330 million yearsago and developed many abilities. Theyare considered as the first animals onland with the ability to live and multiplyon land.
Birds Breathe with lung Beak • Lay eggs on land • Warm - blooded Feathers WingsBack ! More...
Birds are vertebrates, which meansthat they are among those animalsthat posess a backbone. They rangein size from the minute Cuban BeeHummingbird (Calypte helena)(length 8cm/3.5inch) to the grandOstrich (Struthio camelus) lengthupto 9 ft.2inch. Birds areendothermic
Mammals Hair Breathe with lung • Embryo is developed inside mother’s body ( viviparous) • Warm - blooded Mammary glandsBack ! More...
BAT DUCK TOAD TURTLE SHARK
Mammal CharacteristicsAll mammals are warm blooded.Most young are born alive.They have hair or fur on their bodies.Every mammal is a vertebrate.All mammals have lungs to breatheair.Mammals feed milk to their babies.
Bat, duck, toad, turtle & shark With wings Without wingsWith Without With scale Without scalefeathers feather Amphibians Birds Mammals With fins Without fin fish reptiles Back End