Who was the first scientist to see tiny living things for microscope?

What if your blood glucose level is 132? Where do the salivary glands secrete into? Compare a ligament with a tendon? Modified underground stem is? What are the three main divisions of the larynx? What types of molecules are broken down to make ATP which are most often broken down to make ATP? Where does the Krebs cycle occur in humans? What you wear when you swim and also protects your eyes when working? What is the liquid portion of the cytoplasm called? When i wake up every moring my eyes are red and i put eye drops in them that helps alittle and i wear contacts what could it be and the edge of my eye stays red for days they dnt burn what cld it be? What is the definition of homozygus? That evolution by natural selection is occurring in this cactus population? Contained in applies when a properly marked source? What does -3? What are thromboembolytic disorders? What causes an inflammatory response characterized by sneezing or runny nose? What is the job of the diaphram? How many molecules of ATP does fermentation yield? The division of the cell nucleus called? How are nerve cells ensheathed with myelin in the CNS and the PNS?

Who was the first scientist to see tiny living things for microscope?