Diffusion is a ..................... process and is not dependent on .....................

The following figure shows the pathway of transport in the root. What are $P, Q,$ and $R$?

Which property of water allows planktons to move freely on the water surface?

In which form$(s)$ does water exist in nature?

Water is the best transporting medium in plants for dissolved minerals and food molecules. Choose the correct option considering the following properties of water:
$i$. Water is in liquid form at room temperature.
$ii$. Water is the best solvent for most of the solutes.
$iii$. In pure form,its $pH$ is neutral.
$iv$. It is the most active inorganic compound.

Various types of transport mechanisms are needed to fulfill the mineral requirements of a plant. Why are they not fulfilled by diffusion alone?