Answer: "To move substances against a concentration or electrochemical gradient, a cell must use energy. Active transport mechanisms do just this, expending energy (often in the form of ATP) to maintain the right concentrations of ions and molecules in living cells."
so, an example of something that might not be a substrate is the animal itself.
explanation
substrate is the surface of where living animals, live.
sorry if this doesnt help.
HAPPY ALMOST HALLOWEEN
Cancer is a mutation of multiple cells through the cell cycle. cancer doesn’t only effect one cell, but effects many
