What does concentration gradient mean??

Answer 1

It means the amount of something within an area varies.

For instance, if you add a drop of food coloring to the top of a glass of water, the concentration of the coloring would be higher at the top than at the bottom, and an intermediate amount would be in the middle (at least right after it was added. Over time, the coloring would spread out, and the gradient would lessen (the amounts would be more equal) until it was uniform in concentration.

The gradient could be oxygen, pH, a chemical, etc., and the gradient may or may not lessen with time/distance.

Answer 2

concentration gradient refers to places of high concentration compared to low concentration

if a bag of tap water is placed in a bowl of salt water, the tap water has a higher concentration of water, so the tap water moves to the lower concentration, which is the salt water