Sand

Hello to everybody. I admire this Q/A yahoo site so much. I always write answer for a question when I am 200% sure that I know the answer. (of course I don't deserve to be always perfect) I have some more important reasons for being involved in here.... 1. I admire all of my Yahoo friends regardless whether I know or don't know someone; 2. I 'd like to help my students-friends in need; 3. By sharing knowledge I feel satisfied; 4. I also learn while answering and looking for the most correct, reliable answer; and also 5. as a bio-science lecturer, bio-med-tutor and biologist I am also gaining a lot of knowledge. WISH U all the best. SAND I stay at your disposal and wish to be your friend. Enjoy my biology answers. This answer forum is meant for all pre-medical and bio-science students. Wish you GOOD LUCK. SDG