Sycon euplectella spongilla phylum- coelenterata hydra

MZO-05 Vardhman Mahaveer Open University, Kota

MZO-05 Vardhman Mahaveer Open University, Kota

Practical Zoology - I

Convener
SANDEEP HOODA
Department of Zoology
School of Science & Technology
Vardhman Mahaveer Open University, Kota
Members

•Prof. L.R.Gurjar
Director (Academic)
Vardhman Mahaveer Open University, Kota

Director (Regional Centre) MDSU,Ajmer

Vardhman Mahaveer Open

•Dr.M.M.Ranga
Department of Zoology Govt. College, Ajmer

Editing and Course Writing
Editor
Dr. Subhash Chandra, Director (Regional Centre)
Vardhman Mahaveer Open University,
Kota

	Unit		Unit No.
	No.	Dr. Subhash Chandra	2
	1	Dr. Subhash Chandra
Dept. of Zoology ,	1	Director (Regional Centre)

Govt. College, Rajgarh, Alwar

			4
Dept. of Zoology,Govt.		Dept. of Zoology,	4
Dungar College, Bikaner	5	JECRC University Jaipur	6, 7, 8

College, Jaipur

Maharaja Ganga Singh
University, Bikaner

	9		10
		Dept. of Zoology,JNVU
		Jodhpur

Academic and Administrative Management

All Right reserved. No part of this Book may be reproduced in any form by mimeograph or any other means without permission in writing from V.M. Open University, Kota.

Printed and Published on behalf of the Registrar, V.M. Open University, Kota.

	Unit Name	Page No.
Unit -1		72-95 96-107 108-119 120-129 130-142


Unit -3	Study of Prepared Slides (Lower Invertebrates)


Unit -6	Cell Bilogy


Unit -9	Biostatistics Practical

Preface

The present book entitled “Practical Zoology - I” has been designed so as to cover

Structure of the Unit

1.0 Objective
1.1 Introduction
1.2 Study of metazoan nonchordate animal types 1.3 Phylum-Porifera
1.3.1 Leucosolenia
1.3.2. Sycon
1.3.3.Euplectella
1.3.4.Spongilla
1.4 Phylum- Coelenterata
1.4.1 Hydra
1.4. 2 Physalia
1.4. 3 Aurellia
1.4.4 Alcyonium
1.5 Phylum- Platyhelminthes
1.5.1 Fasciola hepatica
1.5.2 Taenia solium
1.6 Phylum- Aschelminthes
1.6.1 Ascaris lumbricoides
1.7 Phylum Annelida
1.7.1 Nereis
1.7.2 Pheretima
1.7.3 Hirudinaria
1.8 Phylum-Mollusca
1.8.1 Chiton

There are large number of animals included in each group/ taxon of the animal kingdom but it is not possible to study all the animals . For each class there is a representative animal which can be best studied by preserving them in formaline /alcohol/stuffing or if such animals is not available due to legal restrictions imposed by the government , being taxonomically significant, it should be studied in a model form or through the diagram for the practical exercises.

1.2 Study of metazoan nonchordate animal types

2. 3.	These are aquatic animals inhabiting all forms of water which remain attached to the substratum or to some objects.

two layers there is cementing mesenchyme.

5. The epidermis is made up of flattened cells –pinacocytes.

asconoid/syconoid/ leuconoid /rhagon types.

9. Skeleton is made up of spicules (calcareous or silicious) and/or spongin

10.

	Reproduce asexually and sexually. Asexual reproduction is by exogenous budding under favourable conditions and by formation of gemmule or reduction bodies under

leuconoid types

2. Class- Hexactinellida-Spicules silicious and six rayed,canal system-

1.3.1. Leucolosenia

Classification :

Order- Homocoela- canal system of asconoid type

Genus- Leucolosenia

attached horizontally at the base which in turn is attached to some rocks.

2. 3.	Skeleton of monoaxon or triaxon calcareous spicules. Choanocytes line the spongocoel.

Habit- Although clustered, they are more independent. Small buds may occasionally apprear at the base of mature specimens.

Characters-
1. Body is vase-like, more or less separate at the base.

	Due to folding of the body covering numerous canals are formed called incurrent canals and radial canals. Canal system of syconoid type stage I. Course of water current is Ostia → incurrent canals → prosopyles → radial canals → apoyles →spongocoel → osculum → outside body. Choanocytes are confined to

	Skeleton of calcareous spicules which are monoaxon, triaxon and tetraxon. Dense spicules almost hide the ostia. Animal is bisexual.

	In sexual reproduction fertilization is internal but cross due to protogynous condition. Development is indirect through amphiblastula larva.

Fig. 1.2 : Sycon – with a portion of body removed to show spongocoel.

1.3.3 Eplectella

Genus- Euplectella.

Habitat- Marine, inhabit deep water at a depth of 500-5000 meter below

2. It is commonly called 'Venus's flower basket'.

5. The osculum is covered by an oscular sieve plate.

6. The canal system of syconoid type, choanocytes are restricted to

7.

Class – Demospongiae – Skeleton of silicious spicules and / or spongin

fibres or absent.

"Fresh water sponge".

5. 6. 7.	Asexual reproduction under unfavourable conditions by gemmule formation.

Fig. 1.4 : Spongilla-colony

1.4 Phylum – Coelenterata (after coelenteron: coel = cavity,

3.	The body is diploblastic, made up of two embryonic germ layers, outer ectodermal-epidermis and inner endodermal - gastrodermis. In between

4.

(=stinging cells) with a structure called nematocyst. These are

characterstic of this phylum only. Due to presence of these structures the

9. There are two stages in the life (i) polyp (ii) medusa.

10. Both the stages show polymorphism. The forms are called zooids.

1. Class – Hydrozoa – Both polyp and medusa are present.

2. Class- Scyphozoa (skyphos = cup. or saucer, zoon = animals) medusa

Phylum – Coelenterata – Presence of coelenteron, tissue grade of

organisation, diploblastic, nematcyst present.

Habitat- Fresh water form, inhabits ponds and lakes.

	The distal end or oral end bears a mouth. Located at this end is a raised

structure called hypostome.

(a)

1-2 ov

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