The following sites provide animations related enzymes

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html
and
http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__enzyme_action_and_the_hydrolysis_of_sucrose.html
and
http://www.lpscience.fatcow.com/jwanamaker/animations/Enzyme%20activity.html

Material for the Mock Brevet

Chapter 7: "Chromosomes, carriers of genetic minformation"
Chapter 8: " Conformed reproduction of genetic information"
Chapter 8: "Sexual reproduction and genetic diversity"
Chapter 1: "Transformation of food into nutrients: digestion" only activity 1 "our food" and activity 2 "chemical transformation of food".
Review the notes on the copybook and the extra exercise sheets and tests.

Answers to activity 2 "chemical transformation of food"

Analysis of the results on page 19: At time initial (o min) the iodine test performed on the contents of test tube A and test tube B gave a dark blue color indicating the presence of starch in the two test tubes while the Fehling test gave a blue color in both test tubes indicating the absence of a reducing sugar. The same tests were performed at the end of the experiment at time = 15 min; the iodine test gave a brown orange color in test tube A indicating the absence of starch and a dark blue color in test tube B indicating that starch is still present. As for the Fehling test it gave a red brick precipitate in test tube A indicating the presence of a reducing sugar and a blue color inn test tube B indicating the absence of a reducing sugar.
Interpretation of the results: in test tube A, starch was hydrolyzed by salivary amylase into the reducing sugar (maltose) thus giving at the end of the experiment a negative identification test with iodine reagent and a positive identification test with the Fehling reagent. In test tube B no hydrolysis occurred since the is no enzyme.
Conclusion: Salivary amylase hydrolyses cooked starch into maltose.

"Nutrition and metabolism"

We started this week a new Unit "Nutrition and metabolism". The animation: organs of digestion illustrates the organs of the digestive system and the path and digestion of food in the digestive tract.
http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter26/animation__organs_of_digestion.html

Wellcome to the 4th regular bio blog

Now the 4eme and 4th regular have separate blogs. I'll be posting reminders, assignments, and topics disscussed in class.