dijous, 29 de maig del 2008

WATER POLLUTION












Water pollution means one or more substances have built up in water to such and extent that they cause problems for animals or people. Oceans, lakes, rivers and other inland waters can naturally clean up a certain amount of pollution by dispersing in hamerssly.The water pollution could affect the health of all the plants, animals,and humans whose lives depend on the river.
Last day we study the germination of seeds in polluting agents.



The material is: x3 erlenmeyer or bottles, distilled water, petri sheet, paper, scissors, permanent marker,100 ml test-tube, lentils or soya seeds, one pipette and one pipum, polluting solution(Na OH, Nh3, Na Cl)one for each group



The procedure:



Take 10 ml of the polluting solution and put them in a test-tube. Fill it with distilled water up to 100 ml.Pour this solution into a new erlenmeyer(bottle) labeled "poluting 0.1".Take 10ml of the "poluting 0.1" solution and put them in a 100 ml test-tube.



Fill the test-tube with distilled water up to 100ml.Pour this solution into a new erlenmeyer(bottle) labeled "poluting 0.01".



How to prepare culture sheet:We take four petri sheets and we put paper in each one. After this we put 10 soya seeds in each petri sheet and we throw the polluting 1M (Nh3, NaOh, Na Cl), in other we throw the 0.1, in other the 0.01, and in the last petri sheet we throw distilled water.We want to wait for a week and in this moment we know what are the result.