Displaying articles by tag: Zoology Notes

BS Media in Cell Biology
Monday, 05 June 2017 19:08

BASIC STRUCTURE OF A PROKARYOTIC CELL

The cells which lack true nuclear membrane are called prokaryotic cells. Blue green algae, bacteria are the examples for prokaryotic cells.   Prokaryotic cells lack chloroplasts mitochondria, Golgi complex and endoplasmic reticulum.   Prokaryotic cells are simple and primitive cells.   In blue green algae cell shows a cell wall,…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Cell Biology
  • Structure of Prokaryotic Cell
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BS Media in Cell Biology
Monday, 05 June 2017 18:46

AN INTRODUCTION TO CELL BIOLOGY (BRIEF HISTORY OF CYTOLOGY)

Cell Biology (Gr., kytos-hollow vessel or cell, logos-to discourse) is a biological science which deals with the study of cells. The cell itself can be regarded as the vital unit of organisms. 'Aristotle' and 'Paracelsus' concluded that "all animals and plants, however, complicated are constituted by few elements which are…

  • Cell Biology
  • Introduction to Cell Biology
  • History of Cytology
  • Notes
  • Zoology
  • Zoology Notes
  • Biology Notes
  • Biology
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BS Media in Zoology
Monday, 05 June 2017 17:46

BALANOGLOSSUS: AFFINITIES AND PHYLOGENETIC RELATIONS

Hemichordates show non-chordate and chordate features. These animals show more non-chordate hence Hyman objected its inclusion in the phylum chordata. Bateson included it in the phylum chordata.   Gegenbaen kept Balanoglossus in Enteropneusta group. Sedgewick and Huxley described its chordate nature. 1887 Bateson kept this in pnyl um chordate.  …

  • Zoology
  • Zoology Notes
  • Notes
  • Article
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BS Media in Zoology
Monday, 05 June 2017 17:26

GENERAL CHARACTERS AND CLASSIFICATION OF HEMICHORDATES

Balfour classified urochordata, cephalochordata and vertebrata as phy­lum chordata. But Bateson included Hemichordata in this phylum chordata. These members are considered as primitive chordata.   The body of these animals is long and worm like. These are marine animals. They make burrows in the coastal sandy shores. Their body is…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • General Characters of Hemichordates
  • Classification of Hemichordates
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BS Media in Zoology
Monday, 05 June 2017 17:04

REPRODUCTIVE SYSTEM, AND EMBRYO DEVELOP­MENT IN BALANOGLOSSUS

Balanoglossus performs asexual and sexual reproduction.   Asexual Reproduction: Gilchrist described asexual reproduction in Balanoglossus capsensis. In the summer season its posterior end will divide into a number of bits. Each bit will develop into a new individual.   Sexual Reproduction: Sexes are separate, sexual dimorphism is absent. The gonads…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Embryo Development in Balanoglossus
  • Reproductive System in Balanoglossus
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BS Media in Zoology
Monday, 05 June 2017 16:34

BLOOD VASCULAR SYSTEM IN BALANOGLOSSUS

Balanoglossus will show open type of blood vascularsystem. It shows   Blood Dorsal sinus Heart Afferent vessel Distributing vessels Collecting vessels.   1. Blood: It is in liquid form. It is colourless. It has no haemoglobin. It contains few blood cells.   2. Dorsal sinus: In the proboscis above the…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Blood vascular system in Balanoglossus
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BS Media in Zoology
Monday, 05 June 2017 16:23

RESPIRATION MECHANISM IN BALANOGLOSSUS

Balanoglossus lives in burrows in the intertidal sandy areas. Its body is long cylindrical. In its pharynx 'U' shaped gills are present with increase in its age the number of gills will increase in number. Each gill has two lobes. These two lobes are separated by tongue bar. This tongue…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Respiration in Balanoglossus
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BS Media in Zoology
Monday, 05 June 2017 16:09

DIGESTIVE SYSTEM OF BALANOGLOSSUS

Balanoglossus is a worm like chordate animal. It is cylindrical organism and lives in burrows of the sand. This animal shows a long alimentary canal and associated glands. This is called digestive system. The alimentary canal starts as mouth and ends with anus.   1. Mouth: It is present on…

  • Zoology
  • Zoology Notes
  • Notes
  • Digestive system of Balanoglossus
  • Article
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BS Media in Zoology
Monday, 05 June 2017 15:51

ANATOMY OF BALANOGLOSSUS

INTERNAL STRUCTURES AND BODY WALL OF BALANOGLOSSUS Balanoglossus is a long cylindrical worm like hemichordate animal. It lives in burrows in the sand of intertidal region.   It's body wall is smooth. It is soft, moist and slimy. It is ciliated. This body wall is helpful in locomotion.   The…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Anatomy of Balanoglossus
  • Internal Structure of Balanoglossus
  • Body Wall of Balanoglossus
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BS Media in Zoology
Monday, 05 June 2017 14:40

WATER VASCULAR SYSTEM IN DIFFERENT ECHINO­DERMS

Water vascular system (or) Ambulacral system is a peculiar system which is seen in only Echinoderms. This system is modified in different ways in the members belonging to different classes of phylum echinodermata.   The water vascular system in Asteroidea is considered as typical system.   1. Water vascular system…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Water Vascular System in Echinoderms
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BS Media in Zoology
Monday, 05 June 2017 14:13

ECHINODERMATA GENERAL CHARACTERS AND CLASSIFICATION

Echinodermata means spiny skinned animals. This name was first proposed by Jacob Kelin (1734) for echi-noids. It was Leuckert (1847) who first established Echinodermata as a distinct group of the animal kingdom.   They are exclusively marine. They are free living. Some are pelagic. Some are creeping on the sea…

  • Zoology
  • Notes
  • Article
  • General Characters of Echinodermata
  • Classification of Echinodermata
  • Zoology Notes
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BS Media in Zoology
Monday, 05 June 2017 13:33

FORMS OF ECHINODERMATA LARVA

Echinoderms are unisexual animals. Sexual dimorphism is absent. Fertilisation takes place in water. The development may be direct or indirect. If the development is indirect it includes larva stages. In different classes of echinoderms, different types of larvae complete the development. The larval form is bilaterally symmetrical. It undergoes metamorphosis…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Echinodermata Larva Forms
  • Forms of Echinodermata Larva
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BS Media in Zoology
Monday, 05 June 2017 12:18

FERTILIZATION AND DEVELOPMENT IN STAR FISH

Star fish is unisexual. Male and female animals are separate. Sexual dimorphism is not seen. Only during the breeding season they can be recognized.   Gonads: Rve pairs of gonads are present in star fish. One pair is present at the base of each arm. The gonads of male are…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Fertilization in Star Fish
  • Development in Star Fish
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BS Media in Zoology
Monday, 05 June 2017 11:41

NERVOUS SYSTEM AND SENSE ORGANS OF STAR FISH

In Star fish the nervous system is primitive and diffuse type. It has no ganglia. It is associated with the epidermis. It has nerve fibres.   J. Smith (1937) divided the nervous system into three parts.   1. Oral or ectoneural system: It is called superficial system, as it is…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Nervous System of Star Fish
  • Sense Organs in Star Fish
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BS Media in Zoology
Monday, 05 June 2017 11:25

BLOOD VASCULAR SYSTEM IN STAR FISH

A true blood vascular sys­tem is absent. In star fish, this system circulates digested food to all body parts. It can be studied under two parts.   Perihaemal system. Haemal system.   1. Perihaemal system: It has many tubular coelomic si­nuses called perihaemal system because they enclose channels or Haemal system.…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Blood Vascular System in Star Fish
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BS Media in Zoology
Monday, 05 June 2017 11:09

WATER VASCULAR SYSTEM IN STARFISH

In Echinoderms a peculiar system is met with. It is filled with sea water, it is called water vascular system or Ambulacral system. The entire system is lined with ciliated epithelium. This system is well developed in Asteroidea. It con­tains Madreporite, stone canal, ring canal, 5 radial canals, Tiedemann's bodies,…

  • Zoology
  • Zoology Notes
  • Notes
  • Article
  • Water Vascular System in Star Fish
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