A substance, such as glucose, will enter a cell following its concentration gradient, from the blood and tissues, through the membrane, and into the cytoplasm. Such movement of glucose has a maximal capacity, does not require energy, and is specific only for glucose. How is the entry of glucose into the cell occurring?

The entry of glucose into the cell is by FACILITATED DIFFUSION.

Explanation:

Facilitated diffusion which is also known as facilitated transport or passive - mediated transport, is the process of spontaneous passive transport of molecules or ions across a biological membrane via specific transmembrane integral proteins.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.