Concentration dependent cellular processes?

Question

Are there any famous biological processes that depend strongly on a chemical concentration reaching a particular value, like some sort of switch? E.g. if concentration of chemical x reaches concentration y at cell location z (membrane, organelle etc) then a particular biological process will occur?Thanks

Answer 1

Great question!

One of the most common process that is dependent on key chemical concentrations is the female reproductive cycle. The concerting of various processes is controlled tightly by hormones. A notable example of these would be the formation of primary follicles. The spread, through stochastic means, of FSH across the ovarian cells causes enough binding of FSH in some oocytes to trigger maturation. If not enough receptors bind FSH, there will not be maturation of the oocyte. If there is enough binding of the FSH receptors, it causes the Gs protein cascade, leading to other downstream maturation effects. In this case, the presence of FSH acts as a gauge whether the cell will mature.

Hope this makes sense to you!