Answer: The answer is regulatory proteins
Explanation: Differential gene expression is the result of different cells containing different regulatory proteins.
Gene can be referred to as a portion or part of hereditary transferred from parent to offspring. Gene can also determine characteristics of the offspring.
Differential gene expression is the process that determines how cells grow.
Cell can be described as the smallest unit of life. It is called the building blocks of life and there are about trillions of cells in the human body.
Proteins are  macronutrients.
