In the light of the carrier concept,the transport of ions across the membrane is:

According to the well-known theory of transport of solutes across a cell membrane,what happens when sugar is passed through it?

$A-$ The symplastic system is the system of interconnected protoplasts.
$R-$ The apoplast is the system of adjacent cell walls that is continuous throughout the plant root,except at the Casparian strips of the endodermis in the roots.

In which method of transport,does the plasma membrane not require a carrier molecule?

By which processes does passive transport occur?

What is active transport?