Silicate Uptake and Silica Shell Formation by Synchronously Dividing Cells of the Diatom Navicula Pelliculosa (Bréb.) Hilse1,2,3

Cells of the freshwater diatom Navicula pelliculosa were induced to divide synchronously by the addition of excess silicate (20 mg Si/liter) to a culture which had been silicate-starved for 14 hr. After a 3- to 4-hr lag period, characterized by rapid silicate uptake (6.5 mg Si/liter/4 hr) and silica shell formation, the cell number then doubled in the succeeding 2-3 hr. This system promises to have significance in the study of silicon metabolism, transport phenomena, and silica deposition.