When prokaryotic bacterial cells undergo cell division, the single circular chromosome replicates to form a second chromosome. This new chromosome, like the original, attaches to the plasma membrane. Next, the plasma membrane pinches inward, and a cell wall forms across the middle of the cell to separate the two chromosomes and form two daughter cells. How does cell division in bacteria differ from mitosis in eukaryotes?

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.