Answer:
Concentration gradient
Explanation:
When the concentration of molecules and ions is compared to the concentration of ions and molecules in another area, the difference in the concentration will be called the concentration gradient.
The concentration gradient is the factor which determines the rate and direction of the molecules and ions in the environment which could be physical or biological.
Thus, concentration gradient is the correct answer.
Answer:
This shows that once animals were on the surface there were plants for them to eat.
Solid:
•Has a definite shape and volume.
•It has the lowest energy.
•These are hard to compress.
Liquid:
•Has a definite volume, but take the shape of the container.
•It has medium energy.
•You can compress them a little difficulty.
Gas:
•Has no definite shape or volume.
•They have the highest energy.
•These are easily compressible.
