CLASS X BIOLOGY

Origin of Life: Evolution can explain formation of many species ultimately from a single  species in the past. But origin of life (first species) needs further explanation. Oparin and Haldane proposed biochemical theory of evolution : Chemical evolution : Formation of simple organic substances (amino acids,  glucose, nucleotides) from inorganic substances CH4, NH3, H2S on primitive Earth. Biological/ Organic Evolution : Formation of first primitive cell using organic  molecules. Evolution of different forms of life forms from simple unicellular  prokaryotic organism Miller and Urey experiment : They simulated primitive earth. Primitive reducing atmosphere             Gases like H2S, NH3, CH4 Evaporation from hot oceans                Boiling water in flask Lightening      ...

Class XA, XB , XC : Prepare a report on the following topics: i) Global warming     (Roll no 1-5) ii) Ozone depletion    (Roll no 6-10) iii) Rain water harvesting   (Roll no 11-15) iv) Biological magnification  (Roll No 16-20) v) The magic 3- Reduce, Recycle and Reuse   (Roll no 21-25) vi) Organic farming  (Roll no 26-30) vii) Carbon footprints- how to reduce them (Roll no 31-35) viii)Vanmahotsava (Plants that can be grown in kitchen garden/community parks.)(Roll no 36-40) ix) Disappearance of House sparrow (Roll no 41-46)