Em? gumw M Spa 596 vag 7 SCIENCE STAN DARD éu u :1 EIGHT féuu 3&6 3:1: 7 ézumi xi: As we present this revised edition of the Science Textbook, we would like to express our deepest gratitude to the learners and the teaching community for their enthusiastic responses. In science some concepts could be subject to change from time to time as new theories and principles are constantly being evolved. We have tried to present facts and concepts of science (both concrete and abstract) in a visually appealing manner without detracting from the content. Activity based learning is now accepted as the basis of science education. These activities should be regarded as a means for openended investigation rather than for verication of principles / content given in the textbook has been designed to facilitate low-cost activities and experiments using locally available materials. With a view to streamlining the activities, we have now segregated them into three groups: I Do - activities to be done by an individual learner. We Do - activities to be done by a group of learners. and We Observe - activities to be demonstrated by the teacher. The third group of activities have a higher degree of difculty or require careful handling as it may involve dealing with chemicals, electricity etc., The More to know snippets in the text represents some unusual and interesting facts or information in which the students need not be examined. The evaluation section is nothing but another space for learning in a different manner. As the focus is on understanding, rote learning is to be discouraged thoroughly. Application of learnt ideas, problem solving skills and critical thinking is to be encouraged. There could be scope for more than one answer to a question, which should be acknowledged always. To facilitate further reference, books and websites have been suggested at the end of each lesson. Suggestions and constructive criticism are most welcome. Valuable suggestions will be duly incorporated. Authors sciencetextbook@mail. 99 com Diversity in Living Organism 1. DIVERSITY I N LIVI NG ORGANISMS Look at some of the plants and animals around you. Do they have the same shape and size? No, they differ in their size, shape and ATIV1-1 WESEE mpoundmicroscope," with5theE structure. Ourworld is filled with many varieties of living organisms. Animals vary in size from the tiny amoeba to the huge blue whale. However, their bodies can adapt to their living condition. 1.1. CELL AS A FUNDAMENTAL UNIT OF LIFE Cell is the structural and functional unit of all living organisms. Cell was discovered by Robert Hooke in 1665. likethenervecellor a1neuron. The Thieodtischwann and Matthias following table shows IJacobiSchileideni postullated. thecell types of cells and their theory in 1e813l9.jfThe1:;itwof important Example: apostullfatlestpf thecellltheorylfarelpz V, I I living jorgafnislms areImalcle , Nervecells I Flamecells the various shape. tar ubular fromthepore-exidstingccellsg. Types ofHuman Cells Related to Function Based on the function, the size and the shape of the cells differ. Generally, cells are round, spherical or elongated. Some cells are long and pointed at both ends. They are spindle shaped. Cells, sometimes, are quite long. Some are branched §Columnar ;MusCleCells 101 . . Diversity in Living Organism Let us learn the functions about of certain the cells cells. 1.2. STRUCTURE and A list is FUNCTIONS OF CELL ORGANELLES provided below : §SquamousLProtective §epithelium shape & give 3 Muscle Cells Contractile & E The cell organelles are present in the cell cytoplasm matrix,which are the living structures of the cytoplasm. They have the properties of growth and multiplication at the time of necessity within the cell. jRetractile 1.2.1.Cell Organelles and their §§5Storing more fat Fat cells Funcons §:droplets §Conduction ofnerve EN The Cell Organelles are ll eweces nmpulses 1. Endoplasmic Reticulum Ci... 2. Ribosome Rods and T .. ; conecells 3. Golgi apparatus Vision& colour 4. Lysosomes §fEar cochlear §Conduction ofsound cells AND 5. Mitochondria fwaves 6. Centrioles Secretory The electron microscopic Porter in 1945 revealed study by a network of membranous system with vacuoles in the endoplasm. This was named as endoplasmic reticulum by Porter loool Cells. in 1952. It is assumed that the endoplasmic reticulum originated by evagination ofthenuclearmembrane. Two types of endoplasmic reticulum have been observed. They are rough ER and smooth ER, based on the presence or absence of ribosome in the ER respectively. 102 Diversity in Living Organism on. a reticulum endoplasmic reticulu T Smoothendoplasmic g Structure of Endoplasmic reticulum a.The and the other a larger unit. The small sub-units occur on the larger unit and form a cap-like structure. The ribosome also may occur freely in the cytoplasm. endoplasmic reticulum provides anultra structural and skeletal framework to the cell. b.The smooth endoplasmic reticulum helps in the synthesis of lipids and in the breaking down of glycogen. c. During cell division, the endoplasmic reticulum membranes disappear and form a new nuclear envelope after each nuclear division. Many minute spherical known as ribosomes remain structures attached with the membrane of endoplasmic reticulum and form the (granular) rough endoplasmic reticulum. The ribosomes are produced in the nucleolus. Each ribosome is composed of two structural units, one smaller T reeresearchers,whomaaethe crystal}structure:of the1ribosofrnesi lreceivedthe. NobelPrizeforchemistry Ifthetyear~e.i..2oO9eyl.:..venkatramiani Rwhakrishnan;anlndianbornU-3-A lScientist}fThl0maS" Steitzrof U-3-A They are the sites of protein synthesis. electron microscopic observation of Golgi bodies reveals the presence of three membranous components,namely, The i. Disc shaped group of flattened sacs or cisternae ii. Small vesicles Diversity in Living Organism may be seen. The mitochondria are bounded by two membranes made of proteins. The outer membrane a. It produces secretory vesicles like forms a bag like structure around the zymogen granules that may have inner membrane, which gives out many finger like folds on the lumen of enzymes inside. iii. Large vacuoles. the b. It forms certain yolk substances in the developing oocytes. c. It helps formation in retinal in the retinal mitochondria. mitochondrial The folds membrane of inner are known as cristae. pigment cells. d. It helps in the formation acrosome in sperm cells. of Lysosomes are a kind of waste disposal system of the cell. Lysosomes originate either from the Golgi apparatus or directly from the endoplasmic reticulum. Each lysosome is of a rounded structure. It is filled with dense material. a. Lysosomes help to keep the cell clean by digesting any foreign material as well as worn-out cell organelles. b. When the cell gets lysosomes may burst enzymes digest their Therefore lysosomes known as suicidal bags damaged and the own cell. are also of a cell. Mitochondria size like filamentous, structure known rounded or rod- as mitochondria to be the power houses of the cell because they are the seat of cellular respiration. They also synthesize the energy rich compound ATP- Adenosine Tri Phosphate. Centrioles were first described by Henneguy and Leuhossek in 1897. The In the cytoplasm of most cells, large are considered centrioles are micro tubular structures, found in two shapes-rods and granules located near the nucleus of the animal 104 cell. At the time of cell division, the centrioles produce spindle fibres and astral bodies. They also decide the plan of cell division. 1.2.2. Nucleus The nucleus is a highly specialised cell organelle which controls all the activities cell. in a cell. It is round It is the or oval brain in outline of a Diversity in Living Organism which overlap one another and are embedded in the nucleoplasm. At the time of cell division, the chromosomes become clearly visible. and possesses four parts. They are : 1. Nuclear The nucleolus is generall Membrane 2. Nucleoplasm present 3. Chromatin the Reticulum cells. in the nucleus The of most of nucleolus become 4. Nucleolus enlarged during active period of The nuclear membrane is the outer cell division and are less developed delicate covering of the nucleus. It in quiescent stage. It is often called contains pores ofdifferentdimensions. as cell organizer. The nucleoplasm protoplasmic substance nucleus. It is also is of the the known as nuclear sap. Chromatin Reticulum is composed of a network with highly elongated chromatin threads Chromatin a. It controls all metabolic processes and hereditary activities of the cell. b. The nuclear membrane exchange of ions between the nucleoplasm and the cytoplasm. 1.3. ORGANIZATION Reticulum allows -- TISSUES ORGAN -- CELLS -- ORGANS - SYSTEM Inmulticellularanimals,cells multiply by the process of cell division and specialise themselves in performing a particular function. For example, the muscle cells perform contraction and relaxation of organs that help in locomotion and conduction. 1.3.1. Tissues A group of cells having common origin, structure and function is referred Diversity in Living Organism Vascular Tissue ~ Epitelial Adipse Tissues A Tissues Muscular Tissues a. Squamous b. Columnar c. Cuboidal a.non T d. Ciliated e. Sensory f. Glandular g. Germinal striated classify animal tissues into five broad categories. Epithelial tissues cover most organs and cavities within the body. Since the cells are closely packed, there is very little space between them.The absence of intercellular space is the characteristic of epithelial tissues. The cells to in this the tissue basement remain membrane that Based on the shape, arrangement of cells and the functions, Epithelia are classified into seven types. Epithetirsm Tissue V attached separates it from the other tissues. A. Squamous iSupportive muscle a.cafHage striated b.bone ob. c. areolar Diversity in Living Organism Nucleus Columnar Epithelium Ciliated Epithelium Secretion of enzymes in the stomach and absorption of digested food in the intestine. C. Ctiboidai They remove the dust particles by the vibration of the cilia. E. Senecry pithelium pitheiium The cells of this epithelium are cube shaped. The walls of the ducts and the glands are examples of this type of epithelium. Some of the epithelial cells are modified to respond to stimuli and they form the sense organs. This is a liquid tissue adapted for the transportation of the nutritive materials, respiratory gases, excretory materials and others. It consists of 55% plasma and 45% Nucleus blood cells. There are three kinds of blood cells. Cuboidal Epithelium They are, This tissue helps in secretion and reabsorption of water in kidney tubules. Q. Citiated Epithelium Its structure is like the columnar epithelium. In addition it contains a number of fine protoplasmic projections called cilia. The wind pipe on the trachea is internally lined by ciliated epithelium. 107 i) Red Blood Cells (Erythrocytes) RBC ii) White Blood Cells (Leucocytes) iii) Blood Platelets (Thrombocytes) WBC it Erythrocytes: The Red Blood Cells are present in vast majority. Each red cell is a circular without a nucleus. or biconcave These disc are formed in the bone marrow. Their life span Diversity in Living Organism is between 100 and 120 days. They contain haemoglobin, a respiratory pigment that chiefly carries oxygen from the lungs to the other parts of the body. 3%) Leucocytes: The nucleated white blood cells are irregular and contain no pigment. They are produced in the bone marrow and in the lymph glands. The life span of WBC is two to three ATlVlY .2 different compoundmicroscope~ if i) Cartilage tissue iii) Thrornbccytes: The blood platelets are the smallest ii) Bone tissue of the blood iii) Areolar tissue i) Gartitaga Tissuezw It has widely spaced cells. The solid matrix is composed of proteins and sugars. The cartilage smoothens the bone surface at the joints and is also present in the nose, ear, trachea and larynx. ii) Eons fissuezm It forms the framework that supports the body. cells. They are responsible for the clotting when blood vessels are damaged. The cells of connective tissues are loosely spaced and embedded in an inter cellular matrix. The matrix may be a jelly like fluid, or rigid. They are of two They are Bonecellsarecomposedofcalcium and phosphorous compounds. Two dense types. bones B) Supportive tissue 3:5; Areoiar A) Adipose Tissuww This is modified for storing fat. The inter cellular is more or less absent. between It is found chiefly below the skin and in between the internal organs. 3) Supportive gives support can be connected to each other by the ligament. This tissue is very elastic and the ligaments contain very little matrix. A) Adipose tissue material atulres. : The supportive tissues are of three types. They are : weeks. blood types off lelepithetlsilall ylytissuessty uinderjja1 They are the police force of the body and protect it from disease producing organisms. of the E BSERV t"issm2:~ This tissue to the entire body. 108 Tissuezm It is found the skin and the muscles around the blood vessels, nerves and in the bone marrow. It fills the space inside the organs. It supports the internal organs and helps in repairing the tissues. Diversity in Living Organism The nerve nervous cells called tissue is neurons formed and It consists of elongated cells, also of called nerve fibres. It has highly developed powers of irritability and conductivity.The brain, spinal cord and nerves are all composed of nervous tissues. Neurons: It is a structural unit muscle fibres. This tissue is responsible for movement in our body. Muscular tissue contains proteins called Qontractiie Preteins. There are three types of muscular tissues: of the nervous system. It has a cell body Striated Muscle 8.) Striated lviuscle: Since these muscles are attached to the skeleton, they are also called Skeletal Muscles. Each muscle fibre is a long parallel Neuron 1 T structure with cross in this muscle sided cylindrical striations and are hence named striped muscles. There are a number of nuclei placed near the periphery. They are covered by a membrane called Sarcolemma. called cyton which assumes different shapes in the different regions of the nervous system, and a long tail called Since their contraction is under axon. Neurons may be either rounded conscious control they are also or oval shaped. The protoplasm of called voluntary muscles. the cyton has a number of small dark granules referred to as Nissils bl Nonairiated muscles bodies. The cyton gives out numerous The cells are arranged to form a branches called dendrons. These in sheet of muscular tissue commonly turn, divide into finer branches called found in the wall of the digestive tract, dendrites. 109 Diversity in Living Organism functions. For example, the eye, has epithelial tissue, connective tissue, nervous tissue and muscular tissue. We have many such organs in our body like eyes, ears, lungs, etc. Now let us study in detail structure of the eyes. Diagram :Nonstriated Muscles urinary bladder and other internal organs. They are not under the control of our willpower. So, they are called involuntary muscles. the The sense organ eye is concerned with vision. The eye which is spherical in shape is kept in the orbit of the skull. cl Cardiac muscle: In structure it is between the striped and unstriped muscles fibres. These are found only The eye is made up of three coats. 1. the outersclerotic in the heart. 2. the middle coat choroid coat They are multi nucleated but the 3. the inner coat (Retina) nuclei are centrally located. Dark and Light bands are present. The f. eiemtio seat muscle of the heart show rhythmic The outer sclerotic coat is white in contraction and relaxation throughout colour except in the front where it forms life. These involuntary muscles are the transparent cornea. called cardiac muscles. 2. The Middle Shdroid seat It is highly vascularised and deeply pigmented. In front of the eye the Nucleus choroid coat forms the iris and lens. An opening called the pupil is present in the centre Cardiac of the Iris. Bhe inner mat {Retina} Retina is the sensitive part of an eye. It contains two types of receptor Muscle cells 1.3.2. ORGANS the rods and cones. Rods are sensitive to different shades of light Two or more kinds of tissues but not to colour. Cones are sensitive associate together to form an organ. to colour. The fovea or yellow spots An organ is a specialized part of of the retina are densely packed with the body performing some specific 110 Diversity in Living Organism Vitreous humor Lens Pupil Sclera system consists of two kidneys, an ureter and an urinary Choroid bladder. Retina F°Vea Thereis a pairof kidneys Ins located inside the abdomen on eitherside of the vertebral 1 column in the lumbar region and against the posterior abdominal wall. The right kidney is slightly on the lower side due to the presence of CrossSection of the eye the liver. The outer surface is convex cones. It is the part, that is used when and the inner surface is concave. The one concentrates on something. concave side is called hilus. e.g. when reading, sewing etc. The lens Avertical section of the kidney shows is transparent, elastic and biconvex in shape. It is attached by ligaments to an outer dark portion called the cortex the ring shaped ciiiary muscles. The and an inner pale region called medulla. aqueous humor is a clear, watery liquid The medulla has a number of cone like between the cornea and the lens. The vitreous humor is a viscous liquid which fill the space between the lens and the retina. Vitreous humor helps in image formation and in maintaining the spherical shape of the eye. 1.3.3. Organ System Several organs of the body together perform a common function. They constitute an organ system. Now let us discuss the excretory system and their functions. Vertical section ofthekidney structures called pyramids. The pelvis projects in between the pyramids as cup like spaces called calyces. Excretion is the elimination of metabolic The kidney contains many minute waste products from the body. The major nephrons.These are the function of the excretory system is the tubular structural and functional units of the elimination of nitrogenous waste products from the body. The mammalian urinary kidney. Diversity in Living Organism Fer exempts Bowmancap I Glomerulus Proximal convoluted tubule The control of blood glucose level is a good example of homeostasis and «---I---«-- Distal convoluted tubule] it involves the secretion of atleast six hormones. A rise in the blood glucose level stimulates insulin secretion whereas a fall in the blood glucose Loop of Henle level Collecting duct inhibits insulin secretion and stimulates the secretion of glucagon ! Diagram: Structure ofnephron and other harmones which raise blood glucose levels. 0 The kidney not only removes the waste product from the blood but also maintains 1.5. CELLULAR Respiration is the process by which chemical energy in organic molecules is released by oxidation. This energy is then made availabe to living cells in a constant composition of blood. o It maintains the p o The kidney regulates the loss of excess water from the body °'V' -3 RESPIRATION the form of ATP. The BRV occurs biochemical within process cells is which called cell respiration. oweobservethe preservedorgans andmodelsoisomeorganswith If it uses oxygen, it is called as aerobic respiration. If the process takes place in the absence of oxygen, it is termed as anaerobic respiration. 1.4. HoMEos'rAsis Homeostasis of a constant is the maintenance internal environment It of the body. It was first pointed out by the French physiologist Claude Bernard in 1857. All mammals involves the utilisation of free oxygen and results in complete oxidation of glucose into carbondioxide and water. are capable of maintaining a constant body temperature despite changes in the external temperature. Behavioural and physiological responses are two important regulating mechanisms that maintain the stability of Homeostasis. 112 Here oxygen is not utilized for respiration. So, it is called anaerobic respiration. It is often referred to as fermentation. Diversity in Living Organism Glucose > CO2,Water and heat A variety of micro organisms use anaerobic respiration as their major source of ATP E.g. bacteria, yeast. Protein from word The metabolism the Greek word has catabolism its root Metabole which means change. The sum total of the biochemical reactions involved in the release and utilization of energy or energy exchange within the organism is termed as metabolism. Such a chemical reaction in the metabolic process can be divided into two categories. The simple from the substances food are obtained converted into and other from the food are are broken catabolism. The following are examples homeostatic Because of the metabolic process, the ionic balance is being maintained in the body. The metabolic process is responsible for movement, growth, development, maintenance and repair of the cells, tissues and the human body. OF THE BODY - ETS BEAUTY AND -- STRUCTURE FUNCTKDN -- SOME EXAMPLES. structures suit their function and the movements they make. down to produce energy for the purpose of physiological functions of the cells. This process is called as catabolism. and metabolic Likewise, there are various animals that range from unicellular to multicellular organisms whose body steroids. which in the Our body structure suits its function. The human foot, which was originally a climbing structure, has been readapted for bipedal walking and running. Amino acids > Enzymes, hormones, proteins substances anabolism reactions 1.7.. DESlGN Glucose > Glycogen and other sugars Fatty acids > Cholesterol repeated This metabolic process occurs in different organs of living species. For example, obtained acid process maintain the condition of the body. cellular substance. This process is called Anabolism. During this process energy is not involved or utilized. Organic amino Fats > Glycerol, fatty acid, etc. 1.6. METABOLISM The > for Some animal movements are very beautiful. For example, an insect walking on the reverse of a leaf, the soaring of eagles and the running of Jaguar and other animals. 113 Diversity in Living Organism The nature of the flight of an aeroplane differs from that of birds, animals and insects. Planes have fixed wings that create lift when air flows past. They move forward by pushing air through a jet engine or around a propeller very swiftly. The wings of animals do both these jobs at once. When the wings flap downwards, the body of a bird or a bat or an insect is pushed forward and it is Contour is nothing but the shape of kept aloft and stable in its flight. the body. Observe a race horse. Its body has been beautifully designed by nature. The body is spindle-shaped, its streamlined contour offering minimum Soaring of eagle m0. resistance in air. LZ. Bat Bats are the only mammals that truly fly, by flapping their wings. The wing of bat is a fold of skin called patagium supported by all digits of the hand except the first. Now Racehorse The body of fish is also streamlined so that it can freely swim in the water. let us learn about the various shapes of beaks. They have been beautifully designed by nature to suit their feeding habs. figscoopjup}inTtlhe{ Fish Fiohu (Belongs to Kendai) Diversity in Living Organism A sparrow eats seeds it finds on the ground. Its bill helps it to pick up things easily. Aheron gets its food found in water. It lifts fish out of water, and swallows them. Pelicans When a bird eats insects, worms or berries, its bill or beak helps it to get the food it wants. For most birds, bill is a special tool that has the right shape. In fact, the bills of many birds work just like the tools you may have at home. Heron an Find outing type or beaksi iispiarrow, parrot,eagle,duc"k,.pelicjan, . 5etc.,.they.Ca4nichoose:anylf5 aneifhals arldidiraw,'thes'ebeakscithey can-geta cinformation. fronjjbooksyy or{internet.; A S2 rn Z O m Diversity in Living Organism 2. Choose the correct answer : 1. Muscle fibres are branched in B 2. Bone and cartilage are types of B 3. Ciliated epithelium is found in 3. Choose the correct answer (cardiac/ skeletal) muscle. (nerves/ connective) tissues. ................... (trachea / oesophagus) : i) Assertion :The image falls on Fovea ii) Reasoning : Because of refraction of light by vitreous humors a. A is correct B is wrong b B is correct A is wrong c. B explains A d A explains B. ..-.-.7 .iff7ii.§iifiif :7t..t7ft7:iihtiiitf[tiff : .ff 3) Q.il.i§l§.$l. 5. i) Identify part A and part B. ii) How does part A differ from part B ? 6. Our kidneys help our body to lead a healthy life How? 7. Can you name and describe the muscle which is present only in our heart and works throughout our life? 116 Diversity in Living Organism 8. identify the odd item from column A and write it under column B. Write the common features of the other two items in column. 1. Cristae, Matrix,Ribosome 2. Nerve, Muscle, Golgi apparatus 4Aiiihio$iiL;n MA, M3MtermsMVare giveniofi beluga 1 remains odd. Identify the odd item and write it under Column B. Write the common features of the other two under Column C. 9. Copy the diagram of the human eye. Label the following parts: a. the transparent part of the sclera. b. the spot on the retina where cones are most abundant. ;,c__) TTI ._Z l r yaBiology eP.S,Vermayand V.K.Agarvval yChaynd an,clCompany l_td., . TW C Ceill,Biology y:N.ArumuVgaym::iSiaraslPublyioation Tiwebsitesti ymi VC Clwww.users.ron.com/jkiimball.ma,ultranet/b Lj ~ C WWw.eYeidesignbook.com/chib/aieche-ahtrnl 117 Conservation 2. Conservation of Plants and of Plants and Animals Animals 2.1. CONSERVATION OF FOREST AND WILD LIFE timber, fuel wood, gums and leaves. Forest Ranger: Hello Sheelan, Good Morning. Welcome to Topslip. This is one ofthe forest areas in the state, which is rich in biodiversity.This is the Annamalai Tiger Reserve. Fsrest Ranger: You know that they also support living organisms like animals, birds, insects and also many micro organisms. Sheelan : Thank you sir. I was told to meet you and get all information regarding forest and wildlife. Fsrest Ranger: Finel I would be glad to share interesting facts about forests and wildlife with you. Trees, what do they mean to you? Sheelan: Well, trees provide a number of economically valuable commodities, the most important being =.93.. bamboo, resins, Sheelan: Sir, it is said that forests are signs of prosperity. Forest Ranger: You know that they have the capacity to support many lives like animals, birds, insects and fungi. Sheelan: Sir, it is said that forests are signs of prosperity. Forest Ranger: Yes, Forests are of immense economic importance as they are a source of livelihood for many different human settlements as well as governments. They also provide timber and timber products which are a source of income for many people. They are habitats to diverse animal and plant species, they prevent soil erosion and help in maintaining the water cycle. Hence it is important that we should conserve the existing forests covering the Himalayas, the Western 119 Conservation and of Plants and Animals Eastern and start Ghats, establishing more National Parks and sanctuaries and maintaining properly the existing ones. Let us wander into the forest and explore its wonders. India being a subtropical country, the temperature in most parts of the country is conducive to plant growth. Based on this, the forests can be divided into five major types. 1. o Wildlife is an asset to be protected and preserved because of its aesthetic, ecological, educational, historical and scientific . Deciduous values. Peninsular .Tropical Evergreen forests Western Ghats, hilly areas in North Eastern India, The Sub Himalayan belt balance. o Wildlife is a big boost to tourism. o The innumerable plants could yield products of immense . Hilly (mountainous) forests Himalayas, Southern India value. o Wildlife is an important source of genetic material used in genetic engineering I forests region o Wildlife is essential for ecological medicinal Desert (Dry forests) Rajasthan, Southern parts of Punjab & Haryana The . Tidal forest Estuaries of Ganges & Mahanadi. Pratorshadetheidifferent typesofforeists'in;l.ndiar.i 4- DESERTVEGETATIQN ; .- TRoPlcALbEc FOREST.7tiV P..r VTROVPIVCLAL EVEPRGREENL TL 120 r lvlouNTA:N FOREST l.%*rlbAL FOREST Conservation 2.2. DEFORESTATION AND and the common anti-social have been destroying wealth. Deforestation is natural one such dangerousact harming the ecological balance in the hilly areas. The illeffects of deforestation trees is called are afforestation.This is generally done in deserts and open grounds to check the velocity of wind. How can people involve themselves in planting new trees? Afforestation is aimed at two occasions and celebrations. ~CUWTQ =0fd0W 1f0f9$tSfifnGfe.3$eS1. t;h_eT /amount.3of} .c[érb.on r,,d.ioxi.de* 1 theatmospheere, , whichcan ;affect: cl,imatejandf destroy" .h.ontesjtrof;many_ .a.niimajlesVr_7and.l .plants. oerorestatson leadsrto1_soil;,;erosion,4 irregul[ar raiinfallf arfdgilobal.warm.ing'.: :3f*f>4 ' 1 2.3.FLORA ANDi=AuNA India has a large variety of plants, about 45,000 species in number.Of these In India, the Social Forestry Project was started in 1976. Its aim the to rear animals. kinds of forestry programmes such as social forestry and agro forestry. In a locality, Tree lovers Club can be started, and more people can be invited to join these clubs. Tree saplings can be planted on the road side. Sapling can be gifted to friends on special so as to meet Planting of trees in and around agricultural boundaries and on marginal, private lands, in combination with agricultural crops is known as agro-forestry. The land can be used to raise agricultural crops and trees and reduced rainfall, change in climatic conditions. soil erosion and (global warming). The process of planting new man by growing demand for timber, fuel wood, fodder etc. thereby reducing the pressure on the traditional forest area. elements our and Animals also aims at raising plantations AFFORESTATION Selfish of Plants is to promote natural forests and create forests on unused lands. Social forestry o 0 Flowering plants 15,000 Algae 1,676 o 0 Lichens - 1,940 Fungi - 12,480 0 Gymnosperms-64 DEFORESTATION AFFCJRESTAMN 121 Conservation of Plants and Animals _ _c ACTIVTY 2. Lion tailed monkey w DO , Bryophytes _2,843 0 Weidentify thedifferent plants . Pteridophytes _1,012 in ourschool campus andlabel India canbedivided intoeightdistinct them_WC°° amesam floristic regions. botamcal ameS' Indiahasa greatvarietyof fauna ' Wegmwmedi°ia"Vimportam numbering 81,251species,which P'atS _