Identify the water transport pathways $P$ and $Q$ shown in the given figure.

The movement of ions against the concentration gradient is called ........

Active transport is

Active transport of ions by the cell requires

Read the following statements regarding porins and select the correct option given below:
$I$. Porins are transport proteins.
$II$. Channel proteins are a type of transport protein,which are usually gated.
$III$. Carrier protein binds the particular solute to be transported.
$IV$. Particular solute is delivered to the other side of the membrane by carrier proteins.

What are the aquaporins in the facilitated diffusion process?