NUCLEAR ENERGY AND ENVIRONMENTAL CONSEQUENCES

 NUCLEAR ENERGY -

                            THE NUCLEUS OF A HEAVY ATOM LIKE URANIUM , WHEN BOMBARDED WITH LOW ENERGY NEUTRONS , CAN BE BROKEN UP INTO LIGHTER NUCLEI . WHEN THIS IS DONE , A VERY HIGH AMOUNT OF ENERGY IS PRODUCED IF THE MASS OF THE ORIGINAL NUCLEUS IS JUST A LITTLE MORE THAN THE SOME OF MASSES OF THE INDIVIDUAL PRODUCTS.  FOR EX. THE FISSION ON ATOM IS URANIUM PRODUCES 10 MILLION TIMES THE ENERGY AENCRATED BY THE COMBUSTION OF AN ATOM OF CARBON FROM COAL . IN A NUCLEAR REACTOR DESIGN FOR ELECTRIC POWER GENERATION , THIS TYPE OF NUCLEAR FUEL CAN BE A PART OF SELF STAINING FISSION CHAIN REACTION THAT LIBRATES ENERGY AT A CONTROLLED RATE. THE RELEASED ENERGY CAN BE USED TO GENERATE STEAM AND FURTHER PRODUCE ELECTRICITY . 

THE MAJOR HAZARD OF NUCLEAR POWER PRODUCTION IS THE STORAGE AND DISPOSAL OF USED OR SPENT FUELS - THE URANIUM STILL DECAYING INTO HARMFUL SUBATOMIC PARTICLES .  IMPROPER NUCLEAR WASTE DISPOSAL AND STORAGE RESULT IN ENVIRONMENTAL POLLUTION . FURTHER , THERE IS A RISK OF ACCIDENTAL LEAKAGE OF NUCLEAR RADIATION . THE HIGH COST OF INSTALLATION OF NUCLEAR POWER PLANT , HIGH RISK OF ENVIRONMENTAL AND LIMITED AVAILABILITY OF  URANIUM CREATES LARGE SCALE CONSUMPTION OF NUCLEAR ENERGY PROHIBITIVE . 

NUCLEAR ENERGY WAS USED FOR DESTRUCTIVE PURPOSE BEFORE NUCLEAR POWER STATION  WERE DESIGNED. THE FUNDAMENTAL PHYSICS OF THE FISSION CHAIN REACTION IN A NUCLEAR WEAPON IS SAME AS THE PHYSICS OF A CONTROLLED A NUCLEAR REACTOR , BUT THE TWO TYPE OF INSTRUMENT ARE ENGINEERED QUITE DIFFERENTLY . 

ENVIRONMENTAL CONSEQUENCES - 

                                                  DEPLETION OF ANY SOURCE OF ENERGY DISTURB THE ENVIRONMENT IN SOME WAY OR THE OTHER IN ANY GIVEN SITUATION , THE SOURCE WE WOULD SELECT DEPENDS ON FACTORS LIKE THE EASE OF EXTRACTING ENERGY FROM THE ENERGY SOURCE , THE EFFICIENCY OF THE AVAILABLE TECH. AND THE ENVIRONMENTAL DAMAGE THAT WILL BE CAUSED  BY USING THAT SOURCE .  BURNING FOSSIL FUEL CASES AIR POLLUTION . IN SOME CASES , THE ACTUAL OPERATION OF A DEVICE SUCH AS THE SOLAR CELL MAY BE POLLUTION FREE , BUT THE ASSEMBLY OF THE DEVICE WOULD HAVE RESULTED SOME ENVIRONMENTAL DAMAGE . RESEARCH CONTINUES IN THESE AREAS TO CREATE LONG LASTING DEVICE THAT WILL CAUSE LESS DAMAGE THROUGH OUT THEIR WHOLE LIFE .  

NON CONVENTIONAL SOURCE OF ENERGY

 SOLAR ENERGY-

                              THE SUN HAS BEEN RADIATING A LOT OF ENERGY AT THE PRESENT RATE FOR NEARLY 5 BILLION YEARS AND WILL RADIATE AT THAT RATE FOR ABOUT 5 BILLION YEAR MORE . ONLY A LITTLE PART OF SOLAR ENERGY REACHES THE OUTER OTHER LAYER OF THE EARTH ATMOSPHERE . NEARLY ONE HALF IT IS ABSORBED  WHILE PASSING ACROSS THE  ATMOSPHERE AND THE REST REACHES THE EARTH SURFACE . 

A BLACK SURFACE ABSORBS MAXIMUM HEAT AS COMPARED TO A WHITE OR ANY REFLECTING SURFACE UNDER SIMILAR CONDITION . SOLAR COOKER AND SOLAR WATER HEATER USE THIS PROPERTY IN THEIR FUNCTIONING . SOME SOLAR COOKER ATTAIN A HIGHER TEMP. WITH THE HELP OF MIRRORS TO FOCUS TE RAYS OF THE SUN . SOLAR COOKER ARE COVERED WITH A GLASS PLATE COVERING .

THE PRINCIPAL ADVANTAGES RELATED WITH SOLAR CELLS ARE THAT THEY HAVE NO MOVING PARTS, NEED A LITTLE MAINTENANCE AND WORK QUITE SATISFY  IS THAT THEY CAN BE SET UP IN INACCESSIBLE AND REMOTE HAMLETS OR VERY SPARSELY IN HABITAT AREA IN WHICH LAYING OF POWER TRANSMISSION LINE MAY BE COSTLY AND NOT VIABLE COMMERCIALLY . 

ENERGY FROM THE SEA - 

TIDAL ENERGY -

                                  DUE TO THE GRAVITATIONAL FORCE  OF MAINLY THE MOON ON THE SPINING EARTH , THE WATER LEVEL IN THE SEA RISES AND FALLS .  IF YOU LIVE NEAR THE SEA OR EVER TRAVEL TO SOME PLACE CLOSE TO THE SEA , TRY AND OBSERVE HOW THE SEA - LEVEL CHANGES DURING THE DAY . THIS PHENOMENA IS KNOWN AS HIGH AND LOW TIDES AND THE DIFFERENCE IN SEA LEVEL PROVIDE US TIDAL ENERGY . TIDAL ENERGY IS HARNESSED BY BUILDING A DAM ACROSS IN NARROW OPENING TO THE SEA. A TURBINE FIXED AT THE OPENING OF THE DAM CHANGES TIDAL ENERGY TO ELECTRICITY .  

WAVE ENERGY -     

                          THE KINETIC ENERGY PRESENT IN HUGE WAVES NEAR THE SEA - SHORE CAN BE TRAPPED IN SIMILAR MANNER TO PRODUCE ELECTRICITY . THE WAVES ARE CREATED BY STRONG WIND ACROSS THE SEA . WAVE ENERGY WOULD BE A VIABLE PROPOSITION ONLY WHERE WAVES ARE VERY FAST MOVING OR STRONG . A WIDE VARIETY DEVICES HAS BEEN DEVELOPED TO OBSERVE WAVE ENERGY FOR ROTATION OF TURBINE AND GENERATION OF ELECTRICITY . 

OCEAN THERMAL ENERGY - 

                             THE WATER AT THE SURFACE OF THE OCEAN OR SEA IS HEATED BY THE SUN WHILE THE WATER IN DEEPER SECTION IS RELATIVELY COLD. THIS DIFFERENCE IN TEMPERATURE IS EXPLOITED TO GET ENERGY IN OCEAN THERMAL ENERGY CONVERSION PLANTS. THESE PLANTS CAN WORK IF THE  TEMPERATURE CHANGE BETWEEN THE WATER AT THE SURFACE AND DEPTHS UP TO 2 KM IS 293 K OR MORE . THE WARM SURFACE THE WATER IS USED TO BOIL A VOLATILE LIQUID SUCH AS AMMONIA. THE VAPOURS ARE LIQUID ARE THEN USED THE ROTATE THE TURBINE OF GENERATOR. THE COLD WATER OBTAIN FROM THE DEPTH OF THE OCEAN IS PUMPED UP AND AGAIN CONDENSE VAPOUR INTO LIQUID . 

 THE ENERGY POTENTIAL FROM THE SEA IS LARGE, BUT EFFICIENT COMMERCIAL EXPLOITATION IS DIFFICULT.

 

TECHNOLOGY FOR USING CONVENTIONAL SOURCES OF ENERGY

IMPROVEMENTS OF THE TECHNOLOGY FOR USING CONVENTIONAL SOURCES OF ENERGY  - 

1)  BIO- MASS -

                 WOOD HAS BEEN USED AS FUEL FOR A LONG TIME . WE CAN INSURE THAT SUFFICIENT TREES ARE PLANTED , A CONTINUOUS FIRE WOOD SUPPLY CAN BE ASSURED. YOU MAST ALSO KNOWN ABOUT A USE OF COW DANG CAKES AS A FUELS . GIVEN THE  LARGE LIVE STOCK POPULATION IN INDIA, THIS CAN ALSO ASSURE US A STUDY FUELS SOURCES . THESE FUELS ARE ANIMALS AND PLANTS PRODUCTS , THE SOURCES OF THESE FUELS ARE CALLED BIO MASS. FUELS DOES NOT GENERATE MUCH HEAT OF BURNING AND A LOT OF SMOKE IS PRODUCTS WHEN THEY ARE BURNT . THE TECHNOLOGICAL INPUTS IN IMPROVE THE EFFICIENCY OF THESE FUELS ARE ESSENTIAL . WHEN WOOD IS BURNT IN LIMITED SUPPLY OF OXYGEN, VOLATILE MATERIALS AND WATER PRESENT IN IT GET REMOVED AND CHARCOAL IS LEFT BEHIND AS RESIDUE. CHARCOAL BURNS WITHOUT FLAMES, IS COMPARATIVELY SMOKELESS AND HAS A HIGHER HEAT PRODUCTION EFFICIENCY.

BIO GAS IS AN EXCELLENT FUEL AS IT HAS UP TO 75% METHANE . IT BURNS  WITHOUT SMOKE AND LEAVES NO REDUCES  SUCH AS ASH IN WOOD , CHARCOAL AND COAL BURNING . ITS HEATING CAPACITY IS VERY HIGH . BIO GAS IS ALSO UTILISED FOR LIGHTNING . THE SLURRY LEFT BEHIND IS REMOVED PERIODICALLY AND CONSUMED AS EXCELLENT MANURE , REACH IN PHOSPHOROUS AND NITROGEN . THE LARGE SCALE UTILISATION OF BIO WASTE AND SEWAGE MATERIAL GIVES US A SAFE AND EFFICIENT METHOD OF WASTE DISPOSAL BESIDES SUPPLYING MANURE AND ENERGY . 

2)  WIND ENERGY -

                         THE KINETIC ENERGY OF THE WIND CAN BE USED TO PERFORM WORK . THIS ENERGY WAS HARNESSED BY WIND MILLS IN THE PAST TO DO ANY MECHANICAL WORK. FOR EX. IN A WATER LIFTING PUMP , THE RATATIONAL MOTION OF WIND MILL IS USED TO LIFT WATER FROM A WELL . TODAY WIND ENERGY IS ALSO PRODUCED ELECTRICITY . THE WIND MILL ESSENTIALLY CONSIST OF A STRUCTURE IDENTICAL TO A LARGE ELECTRIC FAN THAT IS ERECTED AT SOME HEIGHT ON A RIGID OR TOUGH SUPPORT .

TO PRODUCE ELECTRICITY , THE ROTATORY MOTION OF THE WINDMILL IS UTILISED TO TURN THE TURBINE OF THE ELECTRIC GENERATOR OF OUT PUT OF A SINGLE WINDMILL IS QUIT LITTLE CAN NOT BE CONSUMED FROM COMMERCIAL PURPOSES A NUMBER OF WIND MILL ARE ERECTED OVER A LARGE AREA , WHICH IS CALLED WIND ENERGY FARM . THE ENERGY PRODUCTION OF EACH WIND MILL IN A FARM IS COUPLED TOGETHER TO GENERATE ELECTRICITY ON A COMMERCIAL SCALE .

SOURCE OF ENERGY

WHAT IS A  GOOD SOURCE OF ENERGY ?

WE, IN OUR DAILY LIVES , USE ENERGY FROM DIFFERENT SOURCE FOR DURING WORK . WE CONSUME DIESEL TO RUN OUR TRAINS . WE USE ELECTRICITY TO LIGHT OUR STREET- LAMPS . WE USE ENERGY IN OUR MUSCLE FOR RUNNING CYCLE TO SCHOOL .

THE MUSCULAR ENERGY FOR DOING PHYSICAL WORK, ELECTRICAL ENERGY FOR RUNNING DIFFERENT APPLIANCES , CHEMICAL ENERGY FOR COOKING FOOD OR RUNNING A VEHICLE ALL COME FROM SOME SOURCE .

CONVENTIONAL SOURCE OF ENERGY - 

1) FOSSIL FUELS - 

                                 WOOD WAS THE MOST COMMON SOURCES OF HEAT ENERGY. THE ENERGY OF FLOWING WIND AND WATER WAS ALSO USED FOR LIMITED ACTIVITIES. THE EXPLOITATION OF COAL AS A  SOURCE OF ENERGY MADE THE INDUSTRIAL REVOLUTION POSSIBLE . INCREASING INDUSTRIALISATION  HAS RESULTED A BETTER QUALITY OF LIFE IN THE WHOLE WORLD . IT HAS ALSO CAUSED THE GLOBAL DEMAND FOR ENERGY DEVELOP AT A TREMENDOUS  RATE .THE GROWING DEMAND FOR ENERGY WAS LARGELY FULFILLED BY THE FOSSIL FUELS - PETROLEUM AND COAL. OUR TECHNOLOGIES WERE ALSO DEVELOPED FOR USING THESE ENERGY SOURCE . BUT THESE FUEL WERE PRODUCED OUR MILLIONS  OF YEAR AGO AND THERE ARE ONLY SOME LIMITED RESERVES . THE FOSSIL FUELS ARE NON RENEWABLE SOURCE OF ENERGY, SO WE HAVE TO CONSERVE THEM IF WE CONTINUE CONSUMING . THESE SOURCE AT SUCH ALARMING RATES, WE WOULD SOON WITHOUT ENERGY. IN ORDER TO PREVENT THE ALTERNATE SOURCE OF ENERGY WERE EXPLORED . BUT WE CONTINUE TO WE DEPENDENT LARGELY ON FOSSIL FUEL FOR  MOST OF OUR ENERGY NEEDS .

 

BURNING OF FOSSIL FUEL HAS OTHER DISADVANTAGES TOO . THE OXIDES OF CARBON, SULPHUR AND NITROGEN THAT ARE RELEASED ON BURNING FOSSIL FUELS ARE ACIDIC OXIDES. THESE CAUSES ACID RAIN WHICH AFFECT OUR SOIL AND WATER RESOURCES IN ADDITION TO THE AIR POLLUTION ,RECALL THE GREEN HOUSE EFFECT OF GASES SUCH AS CARBON-DIOXIDE  AND METHANE .

2)  THERMAL POWER PLANT -

                                                             LARGE AMOUNT OF FOSSIL FUEL ARE BURNT IN POWER STATIONS EVERY DAY TO HEAT UP WATER TO FORM STEAM WHICH FURTHER RUNS THE TURBINE TO PRODUCE ELECTRICITY. THE TRANSMISSION OF ELECTRICITY IS MORE EFFICIENT THAN TRANSPORTING PETROLEUM OR COAL OUR THE SAME DISTANCE . MANY THERMAL POWER PLANTS ARE SET UP NEAR OIL OR COAL FIELD . THE TERM THERMAL POWER PLANT IS USED SINCE FUEL IS BURNT GENERATE HEAT ENERGY WHICH IS CHANGED INTO ELECTRICAL ENERGY .

 

3) HYDRO POWER PLANT -

                                              HYDRO POWER PLANTS CHANGES THE POTENTIAL ENERGY OF FALLING WATER INTO ELECTRICITY .SINCE THERE ARE FEW WATER FALLS WHICH COULD BE UTILISED AS A SOURCE OF POTENTIAL  ENERGY,HYDRO POWER PLANTS ARE RELATED WITH DAMS .IN THE LAST CENTURY A LARGE NO OF DAMS WERE CONSTRUCTED ALL OVER THE WORLD.IN ORDER TO GENERATE HYDEL ELECTRICITY,HIGH RISE DAMS ARE BUILT ON THE RIVER TO OBSTRUCT THE FLOW OF WATER AND THERE BY COLLECT WATER IN BIG RESERVOIRS . THE WATER LEVEL INCREASES AND THIS PROCESS THE KINETIC ENERGY OF FLOWING WATER GETS CONVERTED INTO POTENTIAL ENERGY .THE WATER FROM THE HIGH LEVEL IN THE DAM IS ALLOWED TO FALL THROUGH PIPES,TO THE TURBINE AT THE BOTTOM OF THE DAM.

DISPERSION OF WHITE LIGHT BY A GLASS PRISM, RAINBOW AND ATMOSPHERIC REFRACTION

 DISPERSION OF WHITE LIGHT BY A GLASS PRISM -

                                                             THE  PRISM HAS SPLIT THE INCIDENT WHITE LIGHT INTO A BEAUTIFUL BEND OF COLOURS . THE COLOURS THAT APPEAR AT TWO ENDS OF THE COLOUR BAND . THE DIFFERENT COLOUR SEEN ARE VIOLET, INDIGO BLUE GREEN YELLOW, ORANGE AND RED. THE BAND OF THE COLOURED COMPONENTS OF A LIGHT BEAM IS KNOWN AS SPECTRUM . SOME THING MAKES IT COLOUR SEPARATE FROM THE OTHER . THE SPLITTING OF THE LIGHT INTO IT SEVEN COLOUR IS KNOWN AS  THE DISPERSION .

 

ISAAC NEWTON WAS THE FIRST  WHO USE A GLASS PRISM TO GET THE SPECTRUM OF WHITE LIGHT . HE TRIED TO SPLIT OF THE COLOUR OF THE  SPECTRUM  SUNLIGHT FURTHER WITH THE HELP OF SIMILAR PRISM . HE COULD NOT GET ANY MORE COLOUR . HE THINK PUT A SECOND SIMILAR PRISM IN AN INVERTED POSITION WITH RESPECT TO THE FIRST PRISM . THIS ALLOWED ALL THE SEVEN COLOURS OF THE SPECTRUM TO PASS THROUGH THE SECOND PRISM . THIS OBSERVATION GIVE NEWTON THE IDEA THAT THE SUNLIGHT IS COMPOSED SEVEN DIFFERENT COLOURS . 

RAINBOW - 

                    THIS IS NATURAL SPECTRUM. THAT YOU CAN SEE IN SKY AFTER A RAIN SHOWER IT IS DUE TO THE DISPERSION OF SUN LIGHT BY  TINY WATER DROPLETS , PRESENT INTO ATMOSPHERE A RAIN BOW IS ALWAYS APPEARED IN DIRECTION IN OPPOSITE TO THAT OF THE SUN . THE WATER DROPLETS BEHAVE LIKE SMALL PRISM. THEY DISPERSE AND REFRACT THE INCIDENT SUNLIGHT , THAN REFLECT IT INTERNALLY ,AND FINALLY REFRACT IT AGAIN WHEN IT EMERGES OUT OF THE RAINDROP . DUE TO THE INTERNAL REFLECTION AND DISPERSION OF LIGHT ,  DIFFERENT SEVEN COLOUR REACH THE OBSERVE EYE.

 

ATMOSPHERIC REFRACTION -

                                         THE AIR JUST ABOVE THE FIRE BECOMES A HOTTER THAN AIR PRESENT FURTHER  UP . HOTTER AIR IS LIGHTER THAN THE COOLER AIR PRESENT ABOVE IT. THE HOTTER AIR CONTAINS SLIGHTLY LESS REFRACTIVE INDEX THAN THE COOLER AIR THIS RESULT WAVERING OF THINGS THIN THROUGH AIR . SUCH AN OBSERVATION SHOWS AN EFFECT ON REFRACTION OF LIGHT THROUGH THE EARTH ATMOSPHERE  ON A SMALL SCALE IN OUR SURROUNDING . TWINKLING OF STARS IS AN OPTICAL PHENOMENA  IN NATURE.

 

   TWINKLING OF STARS -      

                                    THE TWINKLING OF STARS IS BECAUSE THE ATMOSPHERIC REFRACTION OF STARLIGHT. THE STARLIGHT , AFTER ENTERING THE EARTH ATMOSPHERE UNDERGOES REFRACTION CONTINUOUSLY BEFORE IT COMES TO EARTH . THE ATMOSPHERE REFRACTION TAKE PLACE IN MEDIUM OF GRADUALLY VARYING REFRACTIVE INDEX SINCE THE ATMOSPHERE REFRACTS STARLIGHT TOWARD THE NORMAL, THE APPARENT POSITION OF THE STAR IS SLIGHTLY  DIFFERENT FROM THE REAL POSITION . THE STAR LOOKS SLIGHTLY HIGHER THAN  ITS REAL POSITION WHEN VIEWED NEAR THE HORIZON  THIS APPARENT POSITION OF THE STAR IS NOT STATIONARY BUT KEEP ON  CHANGING SLIGHTLY AND GRADUALLY , SINCE THE PHYSICAL CONDITION OF REFRACTING MEDIUM ARE NOT  STATIONARY . THE APPARENT POSITION OF STAR FLUCTUATES AND THE PATH OF BEAM OF LIGHT COMING FROM THE STAR GOES ON CHANGES SLIGHTLY . 

 ADVANCE SUNRISE AND DELAYED SUNSET -

                                                            THE SUN IS VISIBLE TO US ABOUT TWO MIN. BEFORE THE SUNRISE ABOUT TWO MIN. AFTER THE SUNSET DUE TO THE ATMOSPHERIC REFRACTION . BY SUNRISE WE MEAN THE CROSSING OF THE HORIZON BY SUN. 

THE DIFFERENCE TIME  BETWEEN SUNSET THE APPARENT SUNSET IS ABOUT TWO MIN. THE APPARENT FLATTING OF THE DISC OF THE SUN AT SUNRISE AND SUNSET IS ALSO BECAUSE OF   SAME PHENOMENON  .

SCATTERING OF LIGHT

 AROUND US GIVES RISE TO VARIOUS SCATTERING OF LIGHT - 

                                         THE INTERPLAY OF LIGHT WITH OBJECT PRESENT SPECTACULAR PHENOMENA IN NATURE . THE COLOUR IN DEEP SEA, BLUE COLOUR OF THE SKY, THE REDDENING  OF THE SUNSET AND SUNRISE ARE SOME OF THE WONDERFUL PHENOMENA.

 

1)   TYNDALL EFFECT -

                  THE EARTH ATMOSPHERE IS A HETEROGENEOUS MIXTURE OF SMALL PARTICLES. THESE PARTICLES INCLUDE TINY WATER DROPLETS , SMOKE , SUSPENDED PARTICLE OF DUST . WHEN RAYS OF FALLS ON THESE PARTICLE ,  THE PATH OF THE BEAM BECOMES VISIBLE. THE LIGHT REACHES US, AFTER BEING DIFFUSELY REFLECTED BY THESE TINY PARTICLE . THE PHENOMENA OF SCATTERING OF LIGHT BY THE COLLOIDAL PARTICLE OF LEADS TO TYNDALL EFFECT . WHICH PHENOMENA IS OBSERVED WHEN A FINE BEAM OF SUNLIGHT ENTERS A ROOM FILLED WITH SMOKE THROUGH A SMALL HOLE . THESE PHENOMENA OF SCATTERING OF LIGHT MAKES THE PARTICLE VISIBLE .TYNDALL EFFECT CAN ALSO BE SEEN WHEN SUNLIGHT PASSES THROUGH A CANOPY OF A DENSE FOREST . TINY WATER DROPLETS PRESENT IN THE MIST SCATTER LIGHT.

 

 2)  WHY IS THE COLOUR OF THE CLEAR SKY BLUE ?

                                                                          THE MOLECULES OF AIR AND OTHER FINE PARTICLES IN THE ATMOSPHERE HAVE SIZE SMALLER IN COMPARISON IN WAVELENGTH OF VISIBLE LIGHT . THESE ARE MORE EFFECTIVE IN SCATTERING THE LIGHT HAVING SHORTER WAVELENGTH AT THE BLUE END THAN LIGHT HAVING LONGER WAVELENGTH AT THE RED END . THE RED LIGHT CONTAIN A WAVELENGTH OF ABOUT 1.8 TIMES GREATER  THAN BLUE LIGHT . WHEN SUNLIGHT PASSES THROUGH THE EARTH ATMOSPHERE , THE FINE PARTICLE PRESENT IN AIR SCATTER THE BLUE COLOUR MORE STRONGLY IN COMPARISON TO THE RED . THE SCATTERED BLUE LIGHT FALLS ON OUR EYE . IF THE EARTH HAD NO ATMOSPHERE , THERE WOULD NOT TAKEN PLACE ANY SCATTERING . THAN, THE SKY WOULD HAVE APPEAR DARK. THE SKY LOOKS DARK TO PASSENGERS FLYING AT VERY HIGH ALTITUDES , AS SCATTERING IS NOT PROMINENT AT THESE HEIGHTS . 

3)  COLOUR OF THE SUN AT SUNRISE AND SUNSET -

                                                                             THE SCATTERING OF LIGHT THAT HELP YOU UNDERSTAND SEE THE BLUISH COLOUR OF THE SKY AND THE REDDISH APPEARANCE OF THE SUN AT THE SUNRISE OR THE SUNSET.  LIGHT COMING FOR THE SUN NEAR THE HORIZON PASSES ALONG THE THICKER LAYERS OF AIR AND LARGER VARIOUS DISTANCE IN THE EARTH ATMOSPHERE BEFORE REACHING OUR EYES 

 LIGHT FROM THE SUN OVERHEAD WOULD COMPARATIVELY SHORTER DISTANCE . AT  NOON , THE SUN LOOKS WHITE AS ONLY A LITTLE OF THE VIOLET AND BLUE COLOUR ARE SCATTERED . NEAR THE HORIZON,MOST OF THE BLUE LIGHT AND SHORTER WAVELENGTH ARE SCATTERED AWAY BY THE PARTICLE . THE LIGHT THAT FALLS ON OUR EYE IS LONGER WAVELENGTH . THESE PRODUCES TO THE REDDISH APPEARANCE OF THE SUN . 

THE HUMAN EYE

 THE HUMAN EYE - 

                         IS OF THE MOST IMPORTANT AND SENSITIVE SENSE ORGANS. IT MAKE US SEE THE WONDERFUL WORLD AND THE AROUND US. ALL THE SENSE ORGANS, THE HUMAN EYE IS THE MOST IMPORTANT ONE AS IT MAKES THE AS ABLE TO SEE THE BEAUTIFUL , COLOURFUL WORLD AROUND US. 

  HUMAN EYE IS A LIKE CAMERA. ITS LENS SYSTEM PRODUCED AN IMAGE ON A LIGHT SENSITIVE  SCREEN KNOWN AS THE RETINA. LIGHT ENTERS EYE THROUGH A THIN MEMBRANE KNOWN AS THE CORNEA. IT PRODUCES THE TRANSPARENT BULGE ON THE FRONT SURFACE OF THE EYEBALL. THE EYEBALL IS MAINLY SPHERICAL IN SHAPE WITH A DIAMETER OF ABOUT 2.3 CM MOST OF THE REFRACTION RAYS ENTERING THE EYE TAKES PLACE FOR THE OUTER SURFACE OF THE CORNEA. THE CRYSTALLINE LENS MERELY GIVES THE FINER ADJUSTMENT OF FOCAL LENGTH NEEDED TO FOCUS OBJECTS AT DIFFERENT DISTANCES ON THE RETINA. IRIS IS A DARK MUSCULAR DIAPHRAGM. THE PUPIL CONTROL THE AMOUNT OF LIGHT ENTERING INTO THE EYE. THE EYE LENS PRODUCES THEM  AN INVERTED REAL IMAGE OF THE OBJECT ON THE RETINA. THE RETINA IS DELICATE MEMBRANE CONSISTING ENORMOUS NUMBER OF LIGHT SENSITIVE CELLS. THE LIGHT SENSITIVE CELLS GET ACTIVATED UPON AND PRODUCES ELECTRICAL SIGNALS. THESE SIGNALS ARE TRANSMITTED TO THE BRAIN VIA THE OPTIC NERVES THE BRAINS INTERPRETS THESE SIGNAL AND PROCESSES THE INFORMATION AS THAT PERCEIVE OBJECTS AS THEY ARE.                                                                                                                                                                   POWER OF ACCOMMODATION -                                                                                                                                         THE EYE LENS IS FORMED OF A FIBROUS, JELLY LIKE MATERIAL, LIKE MATERIAL. ITS CURVATURE CAN BE CHANGED TO SOME EXTENT BY THE CILIARY MUSCLE . THE MODIFICATION IN THE CURVATURE OF THE EYE LENS CAN THUS CHANGE ITS FOCAL LENGTH . WHEN THE MUSCLES GET RELAXED, THE LENS BECOME THIN . ITS FOCAL LENGTH INCREASES . THIS MAKES US A UNABLE TO SEE DISTANT CLEARLY. INCREASES THE CURVATURE OF THE EYE LENS. THE EYE THAN BECOMES THICKER . CONSEQUENTLY, THE FOCAL LENGTH OF THE EYE LENS. THEN THE FOCAL LENGTH OF LENS DECREASE . THIS MAKES ABLE TO SEE NEARBY OBJECTS CLEARLY . 

   THE ABILITY OF THE EYE LENS TO ADJUST ITS FOCAL LENGTH IS KNOWN AS ACCOMMODATION. THE FOCAL LENGTH  OF THE EYE LENS CAN NOT BE DECREASE BELOW DEFINITE MINIMUM . THE  IMAGE GET BLURRED OR FEEL STRAIN IN THE EYE. TO SEE AN OBJECT DISTINCTLY AND COMFORTABLY , YOU MUST HOLD IT AT ABOUT  25 CM FROM THE EYE . THE MINIMUM DISTANCE WHICH OBJECT CAN BE SEE MOST DISTINCTLY AND COMFORTABLY WITHOUT STRAIN , LAST DISTANCE OF DISTINCT VISION . IT IS ALSO KNOWN AS THE NEAR POINT OF THE EYE IT IS AT INFINITY  FOR A NORMAL EYE .

THE CRYSTALLINE LENS OF OLD AGE PEOPLE THAT IT BECOMES MILKY. THIS CONDITION IS KNOWN AS CATARACT. THIS CAUSE COMPLETE OR PARTIAL LOSS OF VISION. IT IS POSSIBLE TO RESTORE VISION THROUGH A CATARACT SURGERY.  

         

DEFECTS OF VISION AND THEIR CORRECTION .

 DEFECTS OF VISION AND THEIR CORRECTION -

             THE EYE MAY GRADUALLY LOSE ITS ACCOMMODATION POWER. IN THESE CONDITION THE PERSON CAN NOT SEE THE OBJECT COMFORTABLY. THIS VISION BECOMES BLURRED BECAUSE OF THE  REFRACTIVE DEFECTS OF THE EYE .

 

THREE COMMON REFRACTIVE DEFECTS OF VISION :

    MYOPIA - 

                 IT IS ALSO CALLED A NEAR SIGHTEDNESS  . A PERSON SUFFERING FROM MYOPIA CAN SEE NEARBY OBJECT CLEARLY BUT ARE NOT ABLE TO SEE DISTANT OBJECTS DISTINCTLY. A PERSON SUFFERING FROM DEFECT HAS FAR POINT NEARER THAN INFINITY SUCH A PERSON MAY SEE DISTINCTLY UP TO DISTANCE OF FEW METERS IN A MYOPIC EYE , THE IMAGE OF A DISTANT OBJECT IS PRODUCED IN FRONT OF RETINA AND NOT EXACTLY AT THE RETINA ITSELF.

THIS DEFECT MAY ARISE BECAUSE OF : 

1) EXCESSIVE CURVATURE OF THE EYE LENS 

2) ELONGATION  OF THE EYE BALL 

                  THIS DEFECT CAN BE CORRECTED WITH THE HELP OF CONCAVE LENS OF SUITABLE POWER. 

HYPERMETROPIA -                                                                                                                                                                    IT IS ALSO KNOWN AS FAR SIGHTEDNESS. A PERSON WITH HYPERMETROPIA  CAN SEE DISTANT OBJECT CLEARLY BUT CAN NOT SEE NEARBY  OBJECT CLEARLY . THE NEAR POINT , FOR THE PERSON, IS VERY FAR AWAY FROM THE NORMAL NEAR  POINT ( 25 CM )  THIS IS DUE TO THE LIGHT RAYS FROM A NEAR BY OBJECT FOCUSED AT A POINT BEHIND .

THIS DEFECT ARISES EITHER DUE TO :

1)  THE FOCAL LENGTH OF THE EYE LENS IS TOO LONG . 

2)  THE EYE BALL HAS BECOME TOO SMALL.

                               THIS DEFECT CAN BE CORRECTED WITH THE  HELP OF A CONVEX LENS OF APPROPRIATE POWER . 

PRESBYOPIA - 

           THE POWER OF ACCOMMODATION OF THE EYE GENERALLY DECREASES WITH AGEING. FOR MANY PEOPLE THE NEAR POINT RECEDES AWAY GRAUDALLY . IT IS DIFFICULT TO SEE  CLOSE BY OBJECTS DISTINCTLY WITHOUT CORRECTIVE EYEGLASSES . THIS DEFECT IS KNOWN AS PRESBYOPIA. IT ARISE DUE TO THE DIMINISHING FLEXIBILITY  OF THE EYE LENS AND THE GRADUAL WEAKENING OF THE CILIARY  MUSCLE . A COMMON TYPE OF BI-FOCAL LENSES HAVE BOTH CONCAVE AND CONVEX LENS . THE UPPER HAVE A CONCAVE LENS . IT CORRECTED THE DISTANT VISION . THE LOWER PART IS A CONVEX LENS. IT CORRECTS THE NEAR VISION . 

EVOLUTION AND CLASSIFICATION

1)  EVOLUTION AND CLASSIFICATION -                                              

                                   SOME BASIC CHARACTERISTICS WILL BE SHARED BY VARIOUS ORGANISM. THE CELL IS BASIC STRUCTURAL AND FUNCTIONAL UNIT OF LIFE IN ORGANISM. THE CHARACTERISTICS IN THE NEXT LEVEL OF CLASSIFICATION WOULD BE SHARED BY MOST OF THE ORGANISM BUT NOT BY ALL. A BASIC CHARACTERISTICS OF CELL DESIGN THAT  DIFFERS AMONG VARIOUS ORGANISM IN WHETHER THE CELL CONTAIN A NUCLEUS. BACTERIAL CELL DO NOT , WHILE THE CELL OF MOST OTHER ORGANISM DO. AMONG ORGANISM HAVING NUCLEATED CELLS . THAT PROPERTY MARKS A VERY BASIC DIFFERENCE IN BODY ORGANISATION , BECAUSE OF SPECIALISATION OF CELL TYPE AND TISSUES . IN MULTI CELLULAR ORGANISMS , THEY CAN PERFORM PHOTOSYNTHESIS OR NOT WILL PROVIDE THE NEXT LEVEL OF CLASSIFICATION . AMONG THE MULTI CELLULAR ORGANISM CAN NOT PERFORM PHOTOSYNTHESIS , WHETHER SKELETON PRESENT INSIDE THE BODY OR AROUND THE BODY WILL MARK ANOTHER FUNDAMENTAL DESIGN CHANGE . WE CAN SEE THAT , EVEN IN THESE SOME QUESTION THAT WE HAVE ASKED, A HIERARCHY IS DEVELOPING THAT ALLOWS US TO FORM CLASSIFICATION OF GROUPS. 

 THE MORE CHARACTERISTICS TWO SPECIES WILL PRESENT IN COMMON , THE MORE CLOSELY THEY ARE RELATED. AND THE MORE CLOSELY  THEY ARE CO-RELATED , THE MORE RECENTLY THEY WILL HAVE A SAME ANCESTOR. EXAMPLE, A SISTER AND A BROTHER ARE CLOSELY RELATED. THEY HAD COMMON ANCESTORS IN THE FIRST GENERATION NAMELY, THEIR PARENT BEFORE THEM. A GIRL AND HER FIRST COUSIN ARE ALSO RELATED BUT LESS THAN THE GIRL AND HER BROTHER. THIS IS BECAUSE COUSIN COME FROM A COMMON ANCESTORS, THERE GRANDPARENTS,IN THE SECOND GENERATION BEFORE THEM, NOT IN THE FIRST ONE. NOW WE CAN APPRECIATE THAT CLASSIFICATION OF SPECIES IS A REFLECTION OF THEIR EVOLUTIONARY   RELATIONSHIP.  

2)  SEX DETERMINATION -

                                DIFFERENT SPECIES USE VERY SEPARATE STRATEGIES FOR THIS. IN SOME ANIMALS THE TEMPERATURE AT WHICH FERTILISED EGGS ARE PLACED DETERMINED WHETHER THE ANIMALS DEVELOPING IN THE EGGS WILL BE FEMALE OR MALE. IN OTHER ANIMALS SUCH AS SNAILS, INDIVIDUAL CAN CHANGE SEX, SHOWING THAT SEX IS NOT GENETICALLY DETERMINED. IN HUMANS , THE SEX OF THE INDIVIDUAL IS LARGELY  DETERMINED GENETICALLY.  IN OTHER WORDS , THE GENE INHERITED FROM OUR PARENTS DETERMINE WHETHER WE WILL GIRLS OR BOYS. BUT SO FAR, WE HAVE ASSUMED THAT IDENTICAL GENE SETS ARE INHERITED FROM BOTH    PARENTS. THE EXPLANATION LIES IN THE FACT THAT ALL HUMANS CHROMOSOMES ARE NOT PAIRED. MOST HUMAN CHROMOSOMES HAVE A PATERNAL AND MATERNAL COPY, AND WE HAVE 22 SUCH PAIRS.BUT ONE PAIR,KNOWN AS THE CHROMOSOMES,IS ODD IS NOT BEING ALWAYS A PERFECT PAIR.WOMAN HAVE A PERFECT PAIR OF SEX CHROMOSOMES ,BOTH KNOWN AS X. BUT MAN HAVE A MISMATCHED PAIR IN WHICH ONE IS A NORMAL SIZED X WHILE THE OTHER IS SHORT NAMED Y. SO MEN ARE XY , WHILE WOMAN ARE XX. NOW WE CAN WORK OUT THE INHERITANCE PATTERN OF Y AND X WILL BE?

 ALL CHILDREN WILL INHERIT AN X CHROMOSOME FROM THEIR MOTHER REGARDLESS OF WHETHER THEY ARE GIRL AND BOY. THE SEX OF THE CHILDREN WILL BE DECIDED BY WHAT THEY INHERIT FROM THEIR FATHER . A CHILD WHO INHERITS AN Y CHROMOSOMES FROM HIS FATHER WILL BE A BOY , AND ONE WHO INHERITS A X CHROMOSOMES FROM HIM WILL BE A GIRL. C

HEREDITY AND INHERITANCE

 INHERITANCE FROM THE PREVIOUS GENERATION GIVES BOTH A COMMON BASIC BODY ORGANISATION, AS WELL AS SUBTLE CHANGES IN IT, FOR THE NEXT GENERATION. IF ONE BACTERIUM DIVIDES AND THEN THE PRODUCED TWO BACTERIA DIVIDE AGAIN , THE FOUR INDIVIDUAL BACTERIA PRODUCED WOULD VERY IDENTICAL. THERE WOULD BE ONLY VERY MINOR CHANGES BETWEEN  THEM ,GENERATED DUE TO SMALL INACCURACIES IN DNA COPYING. IF REPRODUCTION IS SEXUAL, EVEN GREATER DIVERSITY WILL BE CREATED. 

HEREDITY -

                  THE MOST OBVIOUS RESULT OF THE REPRODUCTIVE PROCESS STILL REMAINS THE GENERATION OF INDIVIDUALS OF SIMILAR DESIGN. THE RULE OF HEREDITY ENSURE THE PROCESS BY WHICH CHARACTERISTICS AND TRAITS ARE RELIABLY INHERITED.

 

RULES FOR THE INHERITANCE OF TRAITS :

   MENDEL CONTRIBUTIONS -

                                                    THE RULES OF THE INHERITANCE OF THESE TRAITS  IN HUMANS ARE RELATED TO THE FACT THAT BOTH THE MOTHER AND FATHER GIVE PRACTICALLY EQUAL AMOUNTS GENETIC MATERIAL TO THE CHILD. THIS SHOW THAT EACH TRAIT CAN BE INFLUENCED BY BOTH MATERNAL AND PATERNAL DNA. THUS FOR EACH TRAIT THERE WILL BE TO DIFFERENT VERSIONS IN EACH CHILD. MENDEL USED VARIOUS CONTRASTING VISIBLE CHARACTERS OF GARDEN PEAS -ROUND SEEDS,SHORT/TALL PLANT AND SO ON. HE TOOK PEA PLANT WITH SEPARATE CHARACTERISTICS , SAY, A TALL PLANT, GENERATED PROGENY FROM THEM, CALCULATED THE PERCENTAGE OF SHORT OR TALL PROGENY.

 

IN THE FIRST PLACE, THERE WAS NO MEDIAN CHARACTERISTICS IN THE FIRST GENERATION, OR F1 ,   PROGENY NO MEDIUM HEIGHT PLANTS. ALL PLANT PRODUCED WERE TALL. THIS INDICATED THAT ONLY ONE OF THE PARENTAL TRAITS WAS OBSERVED, NOT SOME MIXTURE OF THE TWO. PARENTAL TALL PLANT AND THESE F1 TALL PLANT TO REPRODUCE BY SELF POLLINATION. THE PROGENY OF THE PARENTAL TALL PLANTS ARE ALL TALL. THE F2 OR SECOND GENERATION, PROGENY OF THE F1 TALL PLANTS ARE NOT TALL. THIS SHOWS THE BOTH OF SHORTNESS AND TALLNESS TRAITS WERE INHERITED IN THE F1 PLANT, BUT ONLY THE TALLNESS WAS EXPRESSED. 

IN THIS EXPLANATION, BOTH Tt AND TT ARE TALL PLANTS, WHILE ONLY Tt IS A SHORT PLANT TRAIT. IN OTHER WORDS A SINGLE COPY OF 'T'  IS ENOUGH TO PRODUCE THE PLANT TALL, WHILE COPIES NEED TO BE 't' FOR THE PLANT TO BE SHORT. TRAITS LIKE 'T' ARE KNOWN AS DOMINANT TRAITS, WHILE THOSE THAT BEHAVE LIKE 't' ARE KNOWN AS RECESSIVE TRAITS.    

ASEXUAL AND SEXUAL REPRODUCTION

 ASEXUAL REPRODUCTION-   

                                                INVOLVES A SINGLE PARENTS IT RESULT IN OFFSPRING THAT ARE GENETICALLY IDENTICAL TO EACH OTHER AND TO THE PARENT ALL PROKARYOTES AND SOME EUKARYOTES REPRODUCE THIS WAY.THERE ARE SEVERAL DIFFERENT METHODS OF ASEXUAL REPRODUCTION. THEY INCLUDE BINARY FISSION,FRAGMENTATION,BUDDING ETC.

 SEXUAL REPRODUCTION-  

                                            INVOLVES TWO PARENTS. PARENTS PRODUCTIVE REPRODUCTIVE CELL CALLED GAMETES. THAT UNITE TO FORM As offspring .gametes are haploid cells .this means THEY CONTAIN ONLY HALF THE NO OF CHROMOSOMES FOUND IN OTHER CELLS OF THE ORGANISMS. GAMETES ARE PRODUCED BY A TYPE OF CELL DIVISION CALLED MEIOSIS.THE PROCESS IN WHICH TWO GAMETES UNITE IS CALLED FERTILISATION .THE FERTILISED CELL THAT RESULTS IS REFERED TO AS A ZYGOTE. A ZYGOTE IS A DIPLOID CELL,WHICH MEANS THAT IT HAS TWICE THE NO OF CHROMOSOMES A GAMETES.

ASEXUAL VS SEXUAL- 

                                       CELL DIVISION IS HOW ORGANISMS GROW AND REPAIR THEMSELVES .IT IS ALSO HOW MANY ORGANISMS PRODUCE OFFSPRING. FOR MANY SINGLE CELLED ORG. REPRODUCTION IS A SIMILAR PROCESS .THE PARENTS CELL SIMPLY DIVIDES TO FORM TWO DAUGHTER CELLS THAT ARE IDENTICAL TO THE PARENT.IN MANY ORGANISM TWO PARENTS ARE INVOLVED ,AND THE OFFSPRING ARE NOT IDENTICAL TO THE PARENTS .IN FACT,EACH OFFSPRING ARE UNIQUE. THE CHILDREN RESEMBLE THEIR PARENTS BUT THEY ARE NOT IDENTICAL TO THEM .INSTEAD,EACH HAS A UNIQUE COMBINATION OF CHARACTERISTIC INHERITED FROM BOTH PARENTS.

REPRODUCTION IN HUMAN BEING

        IN THIS CHAPTER WE READ ABOUT THE MOST INTRESTED SPECIES,NAMELY HUMAN.  HUMAN BEING ARE USE A SEXUAL MODE OF REPRODUCTION .AND WE KNOW THAT AS WE BECOME OLDER OUR BODIES CHANGE.OUR HEIGHT OR OUR WEIGHT AND WE ACQUIRE TEETH WE EVEN LOSS OLD SO CALLED MILK TEETH AND ACQUIRE NEW ONES.ALL OF THESE ARE VARIATION THAT CAN BE GROUPED UNDER THE NORMAL PROCESS OF GROWTH,IN WHICH THE BODY BECOMES LARGER. BUT IN EARLY TEENAGE YEARS ,A WHOLE NEW SET OF CHANGES TAKES PLACE THAT CAN NOT BE DISCRIBED SIMPLY AS BODY  ENLARGEMENT INSTEAD THE BODY APPEARENCE CHANGES .NEW FUTURES APPEAR PROPORTION CHANGE AND DO NEW SENSATION.

      ON OTHER VIEW THERE ARE ALSO CHANGES OCCURING THAT ARE DIFFERENT BETWEEN GIRLS AND BOYS .IN GIRLS ,BREAST SIZE START TO INCREASE,WITH DARKENING OF THE SKIN OF THE NIPPLES AT THE TIPS OF BREASTS. ALSO GIRLS START TO MENSTRUATE AT AROUND THIS TIME.BOYS START TO HAVE NEW THICK HAIR GROWTH ON THE FACEAND THEIR VOICE START TO CRACK. AND THE PENIS OCCASIONALY START TO BECOME ENLARGED AND ERECT EITHER AT NIGHT OR IN DAYDREAMALL OF THESE CHANGES OCCUR SLOWLY OVER A PERIOD OF MONTH AND YEARS.

            HOWEVER ,WHILE THE BODY OF INDIVIDUALORG ARE TO ITS ADULT SIZE.THE RESOURCE OF THE BODY ARE MAINLY DIRECTED FOR GETTING THIS GROWTH.WHILE THAT IS OCCURING THE MATURATION OF THE REPRODUCTIVE TISSUE STARTS TO MATURE,THIS PERIOD DURING ADOLESCENCE IS KNOWN AS PUBERTY.

  THE MALE REPRODUCTIVE SYSTEM-

                         IS CONSIST OF PORTION WHICH PRODUCE THE GERM CELL AND OTHER PORTION THAT TRANSFERRED .THE GERM CELL TO THE SITE OF FERTILISATION .THE FORMATION OF GERM CELLS OR SPERMS OCCUR IN THE TESTES .THESE ARE PRESENT OUTSIDE THE ABDOMINAL CAVITY IN SCORTUM BECAUSE SPERM PRODUCTION REQUIRE A LOWER TEMP THAN THE NORMAL BODY TEMP. IN ADDITION TO REGULATING THE PRODUCTION OF SPERMS ,TESTOSTERONE BRINGS ABOUT CHANGES IN APPEARENCE OF OBSERVED IN BOYS AT THE TIME OF PUBERTY. THE SPERM PRODUCED ARE DELIVERED THROUGH THE VAS DEFRENSE WHICH JOINS A TUBE COMING FROM THE URINARY BLADDER .THE URETHRA THUS FORMS A COMMAN PASSAGE FOR BOTH THE URINE AND SPERMS .THE SPERMS ARE TINY BODIES CONTAINING MAINLY GENETIC MATERIAL AND A LONG TAIL THAT SPORTS IT TO MOVE TOWARDS THE FEMALE GERM CELL.

 THE FEMALE REPRODUCTIVE SYSTEM -

                              THE EGGS OR FEMALE GERMS CELL ARE MADE IN THE OVARIES .THEY ARE ALSO RESPONSIBLE FOR THE GENERATION OF SOME HORMONES .WHEN A GIRL BABY IS BORN,THE OVARIES ALREADY HAVE THOUSAND OF IMMATURE EGG IN THEM .ON REACHING PUBERTY SOME OF THESE BEGIN TO MATURE. ONE EGG IS FORMED EVERY MONTH BY ONE OF THE OVARIES. THE EGG IS CARRIED FROM THE OVARIES TO THE WOMB ACROSS A THIN OVIDUCT OR FALLOPIAN TUBE .THE TWO OVIDUCTS UNITE INTO ELASTIC BACK LIKE STRUCTURE CALLED UTERUS.THE UTERUS OPEN INTO THE VAGINA BY THE CERVIX .THE SPERMS ENTER THROUGH THE VAGINAL PASSAGE DURING SEXUAL INTERCOURSE .THEY MOVE UPWARDS THE OVIDUCTS .WHERE THEY MAY ENCOUNTER THE EGG THE FERTILISED EGG KNOWN AS ZYGOTE. GETS IMPLANTED IN THE LINING OF THE UTERUS AND START DIVIDING.

                                              HENCE THE THE UTERUS PREPARE ITSELF EVERY MONTH TO RECEIVE AND NURTURE THE GROWING CHILD .THE LINING THICKENS AND IS RICHLY SUPPLIED WITH BLOOD VESSELS TO NOURISH THE GROWING EMBRYO.

                

HOW DO ORGANISM REPRODUCE(SEXUAL METHOD IN FLOWERING PLANT)

SEXUAL REPRODUCTION- 

                        SEXUAL REPRODUCTION IS A NATURAL WAY OF REPRODUCTION AND TAKES PLACE IN ALL MULTI-CELLULAR ORGANISM. THIS PROCESS INVOLVE THE TWO INDIVIDUAL TO PRODUCE OFFSPRING. IN THIS THE MALE AND THE FEMALE GAMETES FUSE TOGETHER AND GIVE RISE TO A NEW CELL.

 WHY THE SEXUAL MODE OF REPRODUCTION ?

                                                        THE PRODUCTION OF TWO NEW CELL FROM INVOLVE COPYING OF THE DNA AS WELL AS OF THE CELLULAR APPARATUS. THE DNA COPYING MECHANISM , AS WE HAVE OBSERVED , CAN NOT BE COMPLETELY ACCURATE AND THE RESULTANT ERRORS ARE A SOURCE OF CHANGES IN POPULATIONS OF ORGANISMS. EVERY INDIVIDUAL ORGANISMS CAN NOT BE SAVED BY VARIATIONS, BUT IN A POPULATION, VARIATIONS ARE IMPORTANT FOR ENSURING THE SURVIVAL OF  THE SPECIES, IT WOULD HENCE MAKE SENSE IF ORGANISMS COME UP WITH REPRODUCTIVE MODES THAT PERMITTED MORE AND MORE VARIATIONS TO BE CREATED.  THUS, TO VARIOUS INDIVIDUAL IN A POPULATION WOULD HAVE QUITE DIFFERENT PATTERNS OF ACCUMULATED VARIATIONS.

                 THE SEXUAL MODE OF REPRODUCTION INCORPORATES SUCH A PROCESS OF COMBINING DNA FROM TWO VARIOUS INDIVIDUALS DURING REPRODUCTION . 

SEXUAL REPRODUCTION OF FLOWERING PLANT -  

                                                      IN ANGIOSPERMS, THE REPRODUCTIVE PART LOCATED IN THE FLOWER. DIFFERENT PART OF FLOWER , PETALS,SEPALS, CARPELS AND STAMENS .CARPELS AND STAMENS ARE THE REPRODUCTIVE PART OF THE FLOWER WHICH CONTAINS THE GERM - CELLS.THE FLOWER MAY BE ASEXUAL ( PAPAYA , WATERMELON) WHEN IT HAVE EITHER CARPELS OR STAMENS OR BISEXUAL(HIBISCUS ,MUSTARD ) WHEN IT CONTAINS BOTH CARPELS AND  STAMENS STAMEN IS THE MALE REPRODUCTIVE PART AND ITS GIVES POLLEN GRAINS THAT ARE YELLOWISH IN COLOUR . 

                      CARPEL IS LOCATED IN THE CENTRE OF THE FLOWER AND IS THE FEMALE REPRODUCTIVE PART. IT IS MADE OF THREE PARTS.THE SWOLLEN BOTTOM PART IS CALLED OVARY.MIDDLE ELONGATED PART IS CALLED STYLE AND THE TERMINAL PART WHICH MAY BE STICKY IS THE STIGMA. THE OVARY HAVE THE OVULE AND EACH OVULE  CONTAINS AN EGG CELL. THE MALE GERM CELL PRODUCED BY POLLEN GRAINS FUSES WITH THE FEMALE GAMETE PRESENT IN THE OVULE . THIS FERTILISATION OR FUSION OF GERM CELL GIVES US THE ZYGOTE WHICH IS ABLE OF GROWING  INTO A NEW PLANT. THUS THERE IS A NEED TO BE TRANSFERRED THE POLLEN FROM THE STAMEN TO THE STIGMA . ON IF THIS TRANSFER OF POLLEN HAPPENS IN THE SAME FLOWERS , IT IS REFERRED TO AS SELF POLLINATION . ON THE OTHER HAND , IF THE POLLEN IS TRANSFERRED FROM ONE FLOWER TO ANOTHER , IT IS CALLED A CROSS-POLLINATION . THIS TRANSFER OF  POLLEN FROM ONE FLOWER TO ANOTHER IS OCCURED BY AGENTS SUCH AS WIND, WATER AND ANIMALS. 

             AFTER THE POLLEN TRANSFERRED TO A SUITABLE STIGMA , IT HAS TO REACH THE FEMALE GERM-CELLS WHICH ARE PRESENT IN THE OVARY . FOR THIS, A TUBE GROWS OUT OF THE POLLEN GRAINS AND TRAVEL ACROSS THE STYLE TO REACH THE OVARY . 

 AFTER FERTILISATION, THE ZYGOTE DIVIDES SEVERAL TIMES TO PRODUCE AN EMBRYO WITHIN THE OVULE . THE OVULE DEVELOPS A TOUGH COVERING AND IS GRADUALLY CHANGED INTO A SEED . THE SEED CONTAINS A EMBRYO OR FUTURE PLANT WHICH DEVELOPS INTO A SEEDLING UNDER APPROPRIATE CONDITIONS. THIS PROCESS IS CALLED GERMINATION .

 

   THE OVARY GROWS RAPIDLY TO PRODUCE A FRUIT,MEANWHILE, THE SEPALS,PETALS, STAMENS,STIGMA AND STYLE MAY SHRIVEL AND FALL OFF. 

                           

HOW DO ORGANISM REPRODUCE (ASEXUAL METHOD)

   REPRODUCTION    THAT INVOLVES  GENERATION OF A DNA COPY AND ADDITIONAL CELLULAR APPARATUS BY THE CELL INVOLVED IN THE PROCESS. DIFFERENT ORGANISMS USE VARIOUS MODES OF REPRODUCTION DEPENDING ON THEIR BODY DESIGN OR ORGANISATION. 

ASEXUAL REPRODUCTION - 

                           IS A TYPE OF REPRODUCTION WHICH DOES NOT INVOLVE  FUSION OF GAMETES OR CHANGE IN THE NUMBER OF CHROMOSOMES THE OFFSPRING THAT ARISE BY ASEXUAL REPRODUCTION BY SINGLE CELL OR  A MULTI-CELLULAR ORGANISM INHERIT GENE OF THAT PARENTS. 

TYPE OF ASEXUAL REPRODUCTION -

1 ) FISSION-

                FOR UNICELLULAR ORGANISMS, FISSION OR CELL DIVISION, RESULT IN THE CREATION  OF NEW INDIVIDUALS. VARIOUS PATTERNS OF FISSION HAVE BEEN OBSERVED. MANY PROTOZOA AND BACTERIA SIMPLY SPLIT INTO TWO EQUAL HALVES DURING CELL DIVISION.  IN ORGANISMS LIKE AMOEBA , THE SPLITTING OF THE TWO CELLS IN DIVISION CAN OCCUR IN ANY PLANE.

              LEISHMANIA (WHICH CAUSE KALA-AZAR), WHICH CONTAIN A WHIP-LIKE STRUCTURE AT ONE END OF THE CELL IN THESE ORGANISMS, BINARY FISSION TAKES PLACE IN A DEFINITE ORIENTATION IN RELATION TO THESE STRUCTURES. OTHER UNICELLULAR ORGANISMS, LIKE THE MALARIAL PARASITE, PLASMODIUM, DIVIDE INTO MANY DAUGHTER CELLS BY MULTIPLE FISSION.

  

2) FRAGMENTATION -

                         IN MULTI-CELLULAR ORGANISMS HAVING RELATIVELY SIMPLE BODY DESIGN, SIMPLE REPRODUCTIVE  METHODS CAN STILL WORK. FOR EXAMPLE, SPIROGYRA, SIMPLY SPLIT INTO SMALLER PIECES UPON MATURATION. THE FRAGMENTS OR PIECES GROW INTO NEW INDIVIDUALS. MANY MULTI- CELLULAR ORGANISMS ARE NOT SIMPLY A RANDOM COLLECTION OF CELLS SPECIALISED CELLS ARE ORGANISED AS TISSUES AND TISSUES ARE ORGANISED INTO ORGANS, WHICH THEN HAVE TO BE KEPT AT DEFINITE OR DIFFERENT POSITIONS IN THE BODY . CELL-BY CELL DIVISION WOULD BE IMPRACTICAL.

3)  REGENERATION -

                             MANY FULLY  DIFFERENTIATED ORGANISMS HAVE THE ABILITY TO PRODUCE NEW INDIVIDUAL ORGANISMS FROM THEIR OWN BODY PARTS. IF THE INDIVIDUAL IS SOMEHOW BROKEN UP OR CUT INTO DIFFERENT PIECES, MANY OF THESE PIECES GROW INTO SEPARATE INDIVIDUALS. FOR EXAMPLE, SIMPLE ANIMALS LIKE PLANARIA AND HYDRA CAN BE BROKEN INTO A NUMBER OF PIECES AND EACH PIECES GROWS INTO A COMPLETE  ORGANISMS.THIS IS CALLED AS REGENERATION. REGENERATION AND PRODUCE A LARGE NUMBER OF CELLS. FROM THESE CELLS, DIFFERENT CELLS UNDERGO VARIATIONS TO BECOME VARIOUS CELL TYPE AND TISSUES. THESE CHANGES OCCUR AND IN AN ORGANISED SEQUENCE REFERRED TO AS DEVELOPMENT.

4)  BUDDING -

                      ORGANISM LIKE HYDRA USE REGENERATIVE CELLS FOR REPRODUCTION IN BUDDING PROCESS. IN HYDRA, A BUD DEVELOPS AS AN OUTGROWTH BECAUSE REPEATED CELL DIVISION AT ONE SPECIFIC SITE. THESE BUDS DEVELOP INTO TINY INDIVIDUAL AND WHEN BECOME FULLY MATURE , DETACH FROM THE PARENT BODY AND PRODUCE NEW INDEPENDENT INDIVIDUAL. 

5) VEGETATIVE PROPAGATION -

                                      THESE ARE VARIOUS PLANT IN WHICH PARTS SUCH AS THE ROOTS, STEM AND LEAVES DEVELOP INTO NEW PLANT UNDER SOME SPECIFIC CONDITIONS. PLANTS , UNLIKE IS MOST ANIMALS, CAN INDEED USE SUCH A MODE OF REPRODUCTION. THIS PROPERTY OF VEGETATIVE PROPAGATION IS USED IN METHOD LIKE LAYERING OR GRAFTING TO PRODUCE MANY PLANT LIKE ROSES, SUGAR CANE OR GRAPES FOR AGRICULTURAL PURPOSES. PLANTS REPRODUCE BY VEGETATIVE PROPAGATION CAN BEAR FLOWER AND FRUITS COMPARATIVELY EARLIER THEN THOSE PRODUCED FROM  SEEDS . SUCH METHOD ALSO MAKE THE PROPAGATION OF PLANT POSSIBLE SUCH AS BANANA , ORANGE , JASMINE AND ROSE THAT HAVE LOST THE CAPACITY TO PRODUCE SEEDS . ANOTHER ADVANTAGE OF VEGETATIVE PROPAGATION IS THAT ALL PLANTS RAISED ARE GENETICALLY SIMILAR ENOUGH TO THE PARENT PLANT TO CONTAIN ALL ITS  CHARACTERISTICS . 

6) SPORE FORMATION - EVEN IN VARIOUS SIMPLE MULTI-CELLULAR ORGANISM SPECIFIC REPRODUCTIVE ORGAN CAN BE IDENTIFIED . THE THREAD LIKE STRUCTURES THAT PRODUCED ON THE BREAD ARE THE HYPHAE OF THE BREAD MOULD (RHIZOPUS) . THEY ARE NOT REPRODUCTIVE PART . THE TINY BLOB-ON-A-STICK STRUCTURES ARE ALSO TAKE PART IN REPRODUCTION . THE BLOBS ARE SPORANGIA , WHICH HAVE CELLS OR SPORES , THAT CAN EVENTUALLY GROW AND DEVELOP INTO NEW RHIZOPUS INDIVIDUALS. 

EXPLANATION OF DNA AND IMPORTANCE OF INHERITANCE

                          WE HAVE STUDIES THAT THE CHROMOSOMES PRESENT INTO THE NUCLEUS OF A CELL HAVE INFORMATION FOR INHERITANCE OF FUTURE FROM THE PARENTS TO NEXT GENERATION IN THE FORM OF DNA MOLECULE. THE DNA PRESENT INTO THE CELL NUCLEUS IS THE INFORMATION SOURCE FOR PRODUCING PROTEINS .

DNA  (DEOXYRIBO NUCLEIC ACID)

                                 DNA IS THE MOLECULE THAT CONTAINS THE GENETIC CODE OF ORGANISM .THIS INCLUDE ANIMALS ,PLANTS,PROTISTS,BACTERIA AND ARCHEA.

DNA IS IN EACH CELL IN THE ORGANISM AND TELLS CELLS WHAT PROTEIN TO MAKE. MOSTLY THESE PROTEINS ARE ENZYMES .DNA IS INHERITATED BY CHILDREN FROM THEIR PARENTS .THIS IS WHY CHILDREN SHARE TRAITS WITH THE PARENTS SUCH AS SKIN,HAIR AND EYE COLOUR.

STRUCTURE OF DNA- 

                        DNA HAS A DOUBLE HELIX SHAPE WHICH IS LIKE A LADDER TWIST INTO A SPIRAL .EACH STEP OF THE LADDER IS THE PAIR OF NUCLEOTIDES.

NUCLEOTIDE-  THIS IS MADE UP OF

 DEOXYRIBOSE (A KIND OF SUGAR WITH 5 CARBON ATOM)

A PHOSPHATE (MADE UP OF PHOSPHOROUS AND OXYGEN)

AND NITROGENUS BASE

DNA MADE UP OF 4 TYPE OF NUCLEOTIDE-

1)ADENINE                                  2)THYMINE

3)CYTOSINE                                4)GUANINE

PROTEIN SYNTHESIS- 

                   A SECTION OF DNA THAT CONTAINS INSTRUCTION TO MAKE A PROTEIN IS CALLED A GENE.EACH GENE HAS THE SEQUENCE FOR AT LEAST ONE POLYPEPTIDE.PROTEINS FORMS STRUCTURE AND ALSO FORM ENZYMES .THE ENZYMES DO MOST OF THE WORK IN CELLS.THE PROTEINS ARE MADE OUT OF SMALLER POLYPEPTIDES WHICH ARE FORMED OF AMINO ACID .

           GENES ENCODED IN DNA ARE TRANSCRIBED INTO MESSENGER RNA (mRNA) BY PROTEINS SUCH AS RNA POLYMERASE. MATURE mRNA IS THEN USED AS A TEMPLATE FOR PROTEIN SYNTHESIS BY THE RIBOSOMES . RIBOSOMES READ CODON ,WORDS MADE OF THREE BASE PAIRS THAT TELL THE RIBOSOME. WHICH AMINO ACID TO ADD .THE RIBOSOME SCANS ALONG AN mRNA ,READING THE CODE WHILE IT MAKES PROTEIN. ANOTHER RNA CALLED tRNA HELPS MATCH THE RIGHT AMINO ACID TO EACH CODON. 

THE IMPORTANCE OF INHERITANCE-

                             THE PROCESS OF INHERITANCE IS HUGELY IMPORTANT FOR UNDERSTANDING THE COMPLEXITY OF LIFE ON EARTH, IN PARTICULAR FOR ITS ROLE IN SEXUAL REPRODUCTION AND EVOLUTION . FOR THIS MADEL CONTRIBUTIONS TO SCIENCE, BIOLOGY AND GENETICS ARE STILL WIDELY RECOGNISED AND APPLAUDED WITHIN THE SCIENTIFIC COMMUNITY.

 

                      POPULATION OF LIVING BEINGS FILL WELL-DEFINED PLACES , OR NICHES , IN THE ECOSYSTEM , USING THEIR ABILITY TO REPRODUCE. DURING REPRODUCTION THE CONSISTENCY OF DNA COPYING IS ESSENTIAL FOR THE MAINTENANCE OF BODY DESIGN FEATURES THAT PERMIT THE ORGANISMS TO USE THAT PARTICULAR NICHE. REPRODUCTION IS THEREFORE RELATED TO THE STABILITY OF POPULATIONS  OF   SPECIES. 

TRANSPORTATION IN HUMAN BEING NCERT

              WE HAVE STUDIED THAT BLOOD IS A FLUID CONNECTIVE TISSUE.BLOOD HAVE OF FLUID MEDIUM CALLED PLASMA IN WHICH THE CELLS ARE SUSPENDED.PLASMA TRANSPORT FOOD ,NITROGENEOUS WASTE AND CO2 IS DISSOLVED FORM ,OXYGEN IS TRANSPORTED BY THE R.B.C. MANY OTHER SUBSTANCES LIKE SALT ALSO CARRIED BY THE BLOOD .HENCE WE NEED A PUMPING ORGAN TO PUSH BLOOD AROUND THE WHOLE BODY AND NETWORK OF TUBES TO REACH ALL THE TISSUE AND A SYSTEM IN PLACE TO ENSURE THAT THIS NETWORK IS NOT HARMED.

HEART- HEART IS A MUSCULAR ORGAN THAT PUMPS BLOOD BY CIRCULATORY SYSTEM BECAUSE BOTH OXYGEN AND CARBON DIOXIDE HAVE TO BE TRANSPORTED BY HEART,THE HEART HAS DIFFERENT CHAMBERS TO PREVENT THE OXYGEN .SUCH BLOOD FROM MIXING WITH THE BLOOD CONTAINING CO2. THE CO2 SUCH BLOOD HAS TO REACH THE LUNGS FOR THE CO2 TO BE REMOVED.AND THE OXYGENATED BLOOD FROM THE LUNGS HAS TO BE BROUGHT BACK TO THE HEART.THIS O2 RICH BLOOD IS THEN PUMPED TO THE REST OF THE BODY.

               OXYGEN RICH BLOOD FROM THE LUNGS COME TO THE THIN WALLED .UPPER CHAMBER OF THE HEART ON THE LEFT ,THE LEFT ARTIUM RELAXES WHEN IT IS COLLECTED THUS BLOOD .IF THEN CONTRACTS WHILE THE NEXT CHAMBER THE LEFT VENTRICLE EXPENSE SO GET THE BLOOD IS TRANSVERED IT.WHEN THE MUSCULAR LEFT VENTRICLE CONTRACT IN ITS TURNS..THE BLOOD IS PUMPED OUT TO THE BODY THE DEOXYGENATED UPPER CHAMBER ON THE RIGHT ARTIUM AS IT EXPENDS.

                     AS THE RIGHT ARTIUM CONTRACTS THE CORRESPONDING LOWER CHAMBER .THE RIGHT VENTRICLE DILATES .THIS TRANSFER BLOOD TO THE RIGHT VENTRICLES.WHICH IS TURN PUMPS IT TO THE LUNGS FOR OXYGENATION.SINCE VENTRICALS HAVE TWO PUMP BLOOD INTO VARIOUS ORGAN .THEY HAVE THICKERS MUSCLES HOLES THEN THE ATRIA DO VALVES ENSURE THAT BLOOD DOES NOT FLOW BACKWARDS. WHEN THEARTRIA AND VENTRICAL CONTRACTS.

BLOOD VESSELS- ARTERIS ARE THE VESSELS WHICH TRANSFER BLOOD AWAY FROM THE HEART TO DIFFERNT ORGAN OF THE BODY.  ON REACHING A TISSUE OR ORGAN THE ARTRY DIVIDES INTO SMALLER AND SMALLER VESSEL TO CARRY THE BLOOD TO ALL THE INDIVIDUAL CELLS.THE SMALLEST VESSELS CONTAINS WALLS WHICH ARE ONE CELL THICK AND ARE KNOWN AS CAPALLERIES. EXCHANGE OF MATERIAL BETWEEN THE BLOOD AND THE SURROUNDING CELLS OCCUR ACROSS THIS THIN WALL. THE CAPALLERIES THAN JOIN TOGETHER TO MAKE VEINS THAT TRANSPORT THE BLOOD AWAY FROM THE TISSUE OR ORGAN.

MAINTAINANCE BY PLATELETS- IN THE SITUATIONS WHEN WE ARE INJURED AND START BLEEDING NATURALLY THE LOSS OF BLOOD FROM THE SYSTEM HAS TO BE REDUCED.IN ADDITION LEAKAGE WOULD CAUSE LOSS OF PRESSURE WHICH WOU;LD MINIMIZE THE EFFICIENCY OF THE PUMPING SYSTEM.THE BLOOD HAS PLATELET CELLS TO AVOID THIS WHICH CIRCULATE AROUND THE BODY AND PLUG THESE LEAKS BY HELPING TO CLOT THE BLOOD AT INJURY.

MODE OF NUTRITION IN HUMAN BRIEF NOTE

THE ALIMENTARY CANAL IS COILED,MUSCULAR TUBE EXTENDING FROM THE MOUTH TO THE ANUS.IT IS ABOUT 6-9 M LONG AND CONSIST OF MANY SPECIALISED SECTION .THESE ARE MOUTH ,ORAL CAVITY,PHARYNX,OESOPHAGUS,STOMACH,SMALL INTESTINE,LARGE INTESTINE,RECTUM AND ANUS.ALSO SOME ACCESARY DISESTIVE ORGAN LIKE SALIVERY GLANDS,PANCREAS,LIVER,AND GALL BLADDER.ARE CONNECTED TO THE MAIN SYSTEM BY THE SERIES OF DUCTS.

           THE MOUTH IS AN OPENING AND IS PROTECTED BY UPPER AND LOWER LIPS.IT LEADS INTO THE ORAL CAVITY THAT HAS TWO LATERAL WALLS,AN ANTERIOR ROOF ,A POSTERIOR ROOF AND A PAIR OF JAWS.

THE ORAL CAVITY LEADS THROUGH THE PHARYNX INTO THE TUBE LIKE OESOPHAGUS WHICH RUNS DOWNWARDS THROAT AND THORAX .AND THE STOMACH IS A LARGE MUSCULAR C SHAPED SAC AND LOCATED ON LEFT SIDE IN UPPER PORTION OF THE ABDOMINAL CAVITY. IT HAS THREE REGIONS -FUNDUS ,BODY AND PYLORUS. PYLORUS IS GUARDED BY SPHINCTER MUSCLES AND OPENS INTO THE FIRST SECTION OF THE SMALL INTESTINE CALLED DUODENUM WHICH IS U SHAPED.THE COMMON BILE DUCT OPENS INTO THE DUODENUM AND DRAINS INTO ITS JUICES FROM PANCREAS AND LIVER.THE DUDENUM LEADS INTO JEJUNUM .WHICH IS ALSOA BITCOILED AND LONGER.THE LAST PART OF THE SMALL INTESTINE THE ILEUM IS MUCH LONGER AND MORE COILED.IT OCCUPIES THE LOWER PART OF THE ABDOMINAL CAVITY.

THE SMALL INTESTINE LEADS INTO A MUCH SHORTER LARGE INTESTINE OR COLON.IT IS CALLED LARGE BECAUSE OF ITS LARGER DAIMETER AND THE COLON EMPTIES INTO THE LAST PART OF THE INTESTINE THE RECTUM,WHICH IS A SHORTAGE CHAMBER FOR FAECES.

NCERT 10TH LIFE PROCESS(AUTOTROPHS AND HETROTROPHS )

 THE PROCESS WHICH TOGETHER PERFORM THIS MAINTAIN JOB ARE LIFE PROCESS.SINCE,THIS MAINTANANCE PROCESSES WILL BE REQUIRED TO PREVENT DAMAGE AND BREAKDOWN ENERGY IS LIKLY TO BE REQUIRED FOR THEM.

    

                   THE GENERAL NEED FOR ENERGY AND MATERIALS IN IS NORMAL IN ALL ORGANISM BUT IT IS FULFILLED BY VARIOOUS WAYS.SOME ORG USED SIMPLE FOOD MATERIAL PRODUCED FROM INORGANIC SOURCES IN THE FORM OF CO2 AND H2O  .OTHER ORGANISMS CONSUME COMPLEX SUBSTANCES THESE SUBSTANCES NEED TO BE BROKEN DOWN INTO SIMPLER ONCE BEFORE THEY CAN BE USED FOR THE GROWTH AND DEVELOPMENT OF THE BODY.TO DO THIS ORGANISM USED BIOCATALYST KNOWN AS ENZYMES. THUS THE LIFE OF HETROTROPHS DEPENDS DIRECTLY OR INDIRECTLY ON AUTOTROPHS.SUCH HETROTROPHIC ORGANISMS INCLUDE FUNGI AND ANIMALS.-

AUTOTROPHS-CARBON AND ENEGY REQUIREMENTS OF THE ORGANISM ARE SATISFIED BY PHOTOSYNTHESIS .SIMPLY IT IS THE PROCESS BY WHICH AUTOTROPHS OBTAINED SUBSTANCES FROM THE OUTSIDE AND CHNGED THEM INTO STORED FORMS OF ENEGY THE SUBSTANCE IS TAKEN IN THE FORM OF H2O AND CO2 WHICH IS CHANGED INTO CARBOHYDRATES IN THE PRESENCE OF CHLOROPHYLL AND SUNLIGHT.CARBOHYDRATES ARE USED FOR GIVING ENERGY TO THE PLANT .THIS PROCESS IS CALLED PHOTOSYNTHESIS.

  HETROTROPHS- EVERY ORGANISM IS ADAPTED TO ITS ENVIRONMENT .THE FORM OF NUTRITION VARIES DEPENDING UPON THE KIND AND AND AVAILABILITY OFFOOD MATERIAL AS WELL AS HOW IT IS TAKEN UP BY THE ORGANISM. THERE IS A RANGE OF STRATEGIES BY WHICH THE FOOD IS OBTAINED AND CONSUMED BY THE ORGANISMS.SOME ORGANISM BREAKDOWN THE FOOD MATERIAL OUTSIDE THE BODY AND THEN ABSORB IT. AND SOME OTHER ORG OBTAINED NUTRITRION FROM OTHER ANIMAL OR PLANTS WITHOUT KILLING THEM.THIS NUTRITIVE STRATEGY IS USED BY A VARIETY OF ORGANIISMS LIKE ORCHIDS,CUSCUTA,TICKS,LICE, TAPWORMS AND LEECHES .

HOW DO ORGANISMS OBTAINED THEIR NUTRITION- 

            IN UNICELLULAR ORG,THE FOOD MAY BE TAKEN IN BY THE ENTIRE SURFACE .INSIDE THE FOOD VACUOLE COMPLEX SUBSTANCES ARE SPLIT UP INTO THE SIMPLER ONES WHICH GET DIFFUSE INTO THE CYTOPLASM .THE REMAINING UNDIGESTED MATERIAL IS TRANSFERRED TO THE SURFACE OF THE CELL AND THROWN OUT.

     IN PARAMECIEUM ,A UNICELLULAR ORGANISM THE CELL HAS A FIXED SHAPE AND FOOD IS TAKEN IN AT A SPECIFIC SPOT .FOOD IS TRANSFERRED TO THIS SPOT BY THE MOVEMENT OF CILIA WHICH COVER THE WHOLE SURFACE OF THE CELL.