This document discusses a phytoplankton with a half-saturation constant for iron (Fe) uptake of 0.55 μmol/L and toxicity at Fe concentrations above 0.085 mg/L. Using Michaelis-Menten kinetics, calculate the Fe concentrations at which uptake is 10%, 20%, and 30% of maximal, and determine the percentage of maximal uptake that toxic concentrations represent.

1. a phytoplankton has a half-saturation constant of Fe uptake kf 0.55 imol/L. Fe is toxic to this
organism in excess kf 0.085 mg/L. Use a Mochaelis-Menton mofel to determine at what Fe
concentration it achives 10%, 20%, and 30% of its maximal uptake velocity. what percentage of
maximal uptake would comcentratins be toxic?