Non-living components of $xylem$ tissues are involved in

Active transport differs from passive transport in that active transport

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.

Diffusion occurring along the concentration gradient and mediated by carrier molecules is known as:

In which type of transport is the mediation of carrier molecules specifically required?

$A-$ In an antiport,both molecules move in opposite directions.
$R -$ In symport,only one molecule crosses the membrane in the same direction.