Desmosomes or Tonofibrils are

Who proposed the concept of the unit membrane?

The plasma membrane is:

The diagram given below represents a fluid mosaic model of the plasma membrane. Match the components marked as $A, B, C, D$ and $E$ in the diagram below from the list $(i)$ to $(vii)$.
$(i)$ Sugar $(ii)$ Protein $(iii)$ Lipid bilayer $(iv)$ Integral protein $(v)$ Cytoplasm $(vi)$ Cell wall $(vii)$ External protein

Which function is carried out by the cell organelle '$X$'?

The fluidity of membranes in a plant in cold weather may be maintained by