Which of these is a Semipermeable Membrane $(SP)$ and which is Selectively Permeable $(SL)$? : Plasmalemma

Keeping in view the 'fluid mosaic model' for the structure of the cell membrane,which one of the following statements is correct with respect to the movements of lipids and proteins from one lipid monolayer to the other (described as flip-flop movement)?

Cell recognition is mediated by components of the cell membrane. These components are generally composed of .........

Singer and Nicholson's model of plasma membrane differs from Robertson's model in the

In which of the following conditions should a slice of fresh beet root release more betanin pigment?

$A$: Lipids are arranged within the cell membrane with the hydrophobic tails towards the inner part.
$R$: This ensures that the non-polar tail of saturated hydrocarbons is protected from the aqueous environment.