Quimica

INGENIERIA

DEPARTAMENTO DE IDIOMAS MODERNOS


MOD-2

READ THE FOLLOWING TEXT TO COMPLETE THE FOLLOWING TASKS:

Anton van Leeuwenhoek and the microscope (1632-1723)

The father ofmicroscopy, Anton van Leeuwenhoek of Holland, started as an apprentice in a dry goods store where magnifying glasses were used to count the threads in cloth. He taught himself new methods for grindingand polishing tiny lenses of great curvature which gave magnifications up to 270 diameters, the finest known at that time. This led to the building of his microscopes and the biological discoveriesfor which he is famous. He was the first to see and describe bacteria, yeast plants, the teeming life in a drop of water, and the circulation of blood corpuscles in capillaries. During a long lifehe used his lenses to make pioneer studies on an extraordinary variety of things, both living and non living, and reported his findings in over a hundred letters to the Royal Society of Englandand the French Academy.

Using an instrument the size of his palm, Anton van Leeuwenhoek was able to study the movements of one-celled organisms. Modern descendants of van Leeuwenhoek's lightmicroscope can be over 6 feet tall, but they continue to be indispensable to cell biologists because, unlike electron microscopes, light microscopes enable the user to see living cells in action. Theprimary challenge for light microscopists since van Leeuwenhoek's time has been to enhance the contrast between pale cells and their paler surroundings so that cell structures and movement can beseen more easily. To do this they have devised ingenious strategies involving video cameras, polarized light, digitizing computers, and other techniques that are yielding vast improvements incontrast, fueling a renaissance in light microscopy.

PART I: ANSWER THE FOLLOWING QUESTIONS IN SPANISH: 6,25 PTOS

• WHO IS THE FATHER OF THE MICROSCOPE AND WHY IS HE CALLED THAT WAY? 2,5 PTOS...