BSCBO- 202 B. Sc. II YEAR Anatomy, Embryology and Elementary Morphogenesis DEPARTMENT OF BOTANY SCHOOL OF SCIENCES UTTARAKHAND OPEN UNIVERSITY ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 BSCBO-202 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS SCHOOL OF SCIENCES DEPARTMENT OF BOTANY UTTARAKHAND OPEN UNIVERSITY Phone No. 05946-261122, 261123 Toll free No. 18001804025 Fax No. 05946-264232, E. mail [email protected] htpp://uou.ac.in UTTARAKHAND OPEN UNIVERSITY Page 1 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 Expert Committee Prof. J. C. Ghildiyal Prof. G.S. Rajwar Retired Principal Principal Government PG College Government PG College Karnprayag Augustmuni Prof. Lalit Tewari Dr. Hemant Kandpal Department of Botany School of Health Science DSB Campus, Uttarakhand Open University Kumaun University, Nainital Haldwani Dr. Pooja Juyal Department of Botany School of Sciences Uttarakhand Open University, Haldwani Board of Studies Late Prof. S. C. Tewari Prof. Uma Palni Department of Botany Department of Botany HNB Garhwal University, Retired, DSB Campus, Srinagar Kumoun University, Nainital Dr. R.S. Rawal Dr. H.C. Joshi Scientist, GB Pant National Institute of Department of Environmental Science Himalayan Environment & Sustainable School of Sciences Development, Almora Uttarakhand Open University, Haldwani Dr. Pooja Juyal Department of Botany School of Sciences Uttarakhand Open University, Haldwani Programme Coordinator Dr. Pooja Juyal Department of Botany School of Sciences UTTARAKHAND OPEN UNIVERSITY Page 2 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 Uttarakhand Open University, Haldwani Unit Written By: Unit No. 1. Dr. Prem Prakash 1, 2, 3 & 4 Assistant Professor, Department of Botany, Govt. PG College Dwarahat 2. Dr. Sushma Tamta 5, 6 & 7 Assistant Professor, Department of Botany, DSB Campus, Kumaun University, Nainital 3. Dr. Nishesh Sharma 8 & 10 Assistant Prof., Department of Biotechnology, Chinmaya Degree College, BHEL, Haridwar 4. Dr. Ritu V. Singhal 9 Assistant Prof., Department of Botany, Chinmaya Degree College, BHEL, Haridwar Course Editor Prof. Y.P.S Pangtey Retired Professor, Department of Botany DSB Campus, Kumaun University Nainital Title : Anatomy, Embryology and Elementary Morphogenesis ISBN No. : 978-93-90845-31-6 Copyright : Uttarakhand Open University Edition : 2021 Published By: Uttarakhand Open University, Haldwani, Nainital-263139 UTTARAKHAND OPEN UNIVERSITY Page 3 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 CONTENTS BLOCK-1GENERAL ANATOMY PAGE NO. Unit-1-Tools and Techniques in Plant Anatomy 6-21 Unit-2-Types of Tissues and Anatomy of Root, Shoot and Leaf 22-58 Unit-3-Structure of Vascular tissues 59-82 Unit-4-Normal and Anomalous growth 83-110 BLOCK-2 EMBRYOLOGY PAGE NO. Unit-5- Male Gametophytes 112-135 Unit-6- Female Gametophytes 136-161 Unit-7- Fertilization and Post Fertilization 162-194 BLOCK-3 MORPHOGENESIS PAGE NO. Unit-8- Plant Morphogenesis and Morphogenetic factors 196-220 Unit-9- Plant Growth Regulators 221-241 Unit-10-Physiology of Flowering 242-268 UTTARAKHAND OPEN UNIVERSITY Page 4 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 BLOCK-1 GENERAL ANATOMY UTTARAKHAND OPEN UNIVERSITY Page 5 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 UNIT-1 TOOLS AND TECHNIQUES IN PLANT ANATOMY 1.1 Objectives 1.2 Introduction 1.3 Tools in plant anatomy 1.4 Techniques in plant anatomy 1.5 Summary 1.6 Glossary 1.7 Self Assessment Question 1.8 References 1.9 Suggested Readings 1.10 Terminal Questions UTTARAKHAND OPEN UNIVERSITY Page 6 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 1.1 OBJECTIVES After reading this unit students will be able - • to familiar with the history of microscopy and different parts of compound microscopes. • to learn different techniques of anatomy like sectioning and staining. • to know Mounting media and mounting techniques. • to explain the common stains for plant cells 1.2 INTRODUCTION As in all experimental sciences, research in plant anatomy depends on the laboratory methods that can be used to study cell structure and function. Many important advances in understanding cells have directly followed the development of new methods that have opened novel avenues of investigation. An appreciation of the experimental tools available to the cell biologist is thus critical to understanding both the current status and future directions of this rapidly moving area of science. The elements of the plant cell are the membrane and the protoplast. The protoplast includes the cytoplasm, the nucleus, the plastids, the mitochondria, and other organelles. In the past, the chief objects of study in plant anatomy were the vegetative organs (stem, root, and leaf); today, attention is also given to the structure of flowers, fruits, and seeds. Within the field of plant anatomy there is: (1) Physiological plant anatomy, which is concerned with the links existing between plant structure and internal processes. (2) Ecological plant anatomy, which is the study of environmental effects on plant structure. (3) Pathological plant anatomy, which is the study of the effect of disease-producing agents of a biological, physical, and chemical character on plant structure, and (4) Comparative or systematic plant anatomy, which introduces the comparative study of representatives of the different systematic groups (taxa) - species, genera, families, and so forth for the clarification of their phylogenetic bonds. The basic method used in plant anatomy, or the study of internal plant structure, is the preparation of thin slices which are studied microscopically. From this the science “derives its name (in Greek, anatome means “dissection”). The emergence of the field of plant anatomy is closely related to the invention and perfection of the microscope. The English physicist R. Hooke observed in 1665 the cellular structure of thin slices of cork, elder pith, and wood from various plants, using a microscope of his own improved design. The real founders of plant anatomy, however, are considered to be the Italian biologist M. Malpighi and the English botanist N. Grew, who published the first (1675–79) and the second (1682) works on this subject; in these works the results of a systematic microscopic study of UTTARAKHAND OPEN UNIVERSITY Page 7 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 plant material were presented. Further development came only at the beginning of the 19th century. The German scientist J. Moldenhawer in 1812 and the French researcher R. Dutrochet in 1824 were able to divide plant tissue into its component cells through maceration (soaking). In 1831 the English botanist R. Brown observed the cell nucleus; this achievement, in combination with the studies of the German botanist M. J. Schleiden, played a great role in the founding of cellular theory, whose author was the German biologist T. Schwann (in 1839). Great contributions to the field of plant anatomy were made by the French biologist Edward. van Tieghem and the German biologists Antony de Bary, Carl Von Nageli, K. Sanio, J. Hanstein, and S. Schwendener. 1.3 TOOLS IN PLANT ANATOMY The theoretical knowledge is incomplete without the practical work. Plants are easily available material for the lab studies and their study in the lab adds immense knowledge to the subject. The practical work develops the scientific outlook and makes the rational approach based on facts and figures. For a better observation and defining the anatomical features of the plants in the laboratory we use different tools and techniques. Practical Microscopy: The cells of plants are quite minute and microscopic in size, so cannot be observed by naked eyes. Such objects are visible only under microscopes. Our eye has limited magnification or resolution power so unable to distinguish the objects smaller than 0.1 mm. Moreover the living cells are transparent in ordinary light and cannot be distinguished among various cellular components. The microscopes are the most important tools in the plant anatomy and their magnification power is achieved by lenses of various type. The fascinating world of microorganisms and different anatomical features would have remained unknown had the microscope not been invented. Roger Bacon (1267) described a lens for the first time. However, his observation was not pursued immediately thereafter. In 1590 glass polishers Hans and Zacchrius Jensen constructed a crude type of simple microscope by placing two lenses together, which permitted them to see minute objects. In 1609-1610 Galileo made the first simple microscope with a focusing device and observed the water flea through his microscope. In 1617-1619 the first double lens microscope with a single convex objective and ocular appeared the inventor of which was thought to be the physicist C. Drebbel. This microscope was used to study the cells, plant and animal tissue, and also the minute living organisms. Till then, the name microscope had not been given to this device; the name „microscope‟ was first proposed by Faber in 1625. The credit of developing a compound microscope with multiple lenses goes to Robert Hooke (1665) of England. It was only after 1670 that a cloth merchant of Delft (Holland), Antony van UTTARAKHAND OPEN UNIVERSITY Page 8 ANATOMY, EMBRYOLOGY AND ELEMENTARY MORPHOGENESIS BSCBO-202 Leeuwenhoek (1632-1723), started his hobby of making microscopes. Considerable progress was made in improving the microscope in nineteenth century. Compound Microscope: A compound microscope is the