2. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. CORALS – reef builders to the session on welcom e

3. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Beneficial animals  provides agronomic and Ornamentals nutrition and medicines luxurious materials clothing materials milk and meat

4. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. In India Coral reefs occur in Gulf of Cutch on the west coast. Andaman and Nicobar Islands, Lakshadweep Islands, and in south east coast, CORALS – r eef builders Small plants like Zoanthella living in the coral tissues contribute to the yellow, green and brown colors of some reef forming corals

5. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Coral rocks are actually the skeletal remains, primarily calcium carbonate secreted by living coral polyps. Coral organisms belong to the phylum: Coelentrata. All reef building corals living as large colonies. - reef corals are typically shy, nocturnal feeders. - they can grow only in shallow, tropical seas. - they thrive only in crystal clear waters. - they can’t survive below 20  c. CORALS – r eef builders

6. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies.  During the day, the corals appear more or less lifeless by withdrawing their polyps.  At night time coral polyps stretch out their tentacles, probing the waters for food.  The reef looks like field of flowers. Only in warm waters the coral polyps can extract calcium from the sea water and deposit as calcium carbonate in their skeletons. CORALS – r eef builders

7. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. CORALS - reef builders: Formation Coral reefs are the result of the reproductive activities of millions of coral polyps over several thousand years. Corals spread by producing vast of minute ciliated Planulae larvae, through sexual reproduction. Planula larvae spend free swimming life, Later they settle on rocks and starts a new colony of polyps by repeated fission or budding.

8. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Corals - types

9. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Corals - types

10. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Corals - types

11. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Categories and Structure of Coral Reefs Coral reefs form in regions of the world where there are warm currents, mainly between the Tropics of Cancer and Capricorn. There are 4 main reef types: Fringing, Barrier, Atolls, and patch reefs.

12. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Fringing reefs are coral reefs that grow in shallow waters and border the coast closely or are separated from it by a narrow stretch of water. Fringing (or apron) reefs directly border shorelines This type is seen as a chain of well developed reefs starting from Rameswaram island and extending beyond Tuticorin. They are also present in the Gulf of Cutch. Coral Reefs: types

13. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Barrier reefs are similar to fringing reefs except that they are separated from the shoreline by lagoons that are often deep and wide: {They are situated away from the coast and form the off- shore break waters parallel to the coasts or isolated islands } The famous Great Barrier Reef of North Eastern Australia which is 2012 KM. Long, is the largest of its kind. Coral Reefs: types

14. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Atolls are circular-shaped reefs that form on the rim of submerged volcanic islands. Patch reefs are small, isolated formations that are not attached to a major reef structure. Hawain and Carribian Islands are famous for Atolls. Coral Reefs: types

15. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Corals are having Decorative, Ornamental value [Ex.Corallium nobile used in Jewelllery] Medicinal value [organ pipe coral (Tubipora) used in indigenous system] Importance in the building habitat for Human and other animals.

16. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Coral skeletons 1)are rich in calcium carbonate, magnesium contents, 2)used for building construction purposes and metalling the roads 3)serves as raw materials for the preparation of lime mortar & cement

17. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Coral Reefs provide opportunities for the evolution of a number of fishes associated with coral reefs Old coral reefs served as sea bird sanctuaries and have collected huge deposits of bird droppings (Guano) Coral reefs act as natural barriers against sea erosion and cyclonic storms. Provides unique habitat for large and diverse variety of organisms. In several countries coral reefs helping in the tourism industry.

18. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies.

19. Prepared by T. Madhavan, Lecturer in Zoology, Directorate of School Education., Pondicherry. An Illustration for the students who aspire for medical studies. Encarta Encyclopedia standard international Text book of Zoology (Biology) for XI standard. Mann, K. H., Ecology of Coastal Waters - A Systems Approach, Chapter 6: Coral Reefs, 160-182, 1982 References: