Answer: He invented the first practical microscopes which was used to see bacterial cell.
Step-by-step explanation:
Microscopic study was done by Anton van Leeuwenhoek who was a draper and he had a great interest in microscope. This helped in mixing the lens and making a microscope which was used to see cell.
This microscope had a magnification of 270 x, which was of great help when visualizing such a small organism that was not seen by naked eyes.