The middle lamella is primarily composed of which substance?

Which of the following components are present in the plant cell wall?
$(1)$ Cellulose $(2)$ Protein $(3)$ Galactans $(4)$ Mannans $(5)$ Suberin
$(6)$ Pectin $(7)$ Hemicellulose $(8)$ Calcium carbonate

Each of the following terms has some anatomical significance. What do these terms mean? Explain with the help of line diagrams.
$(A)$ Plasmodesmata
$(B)$ Middle lamella
$(C)$ Secondary wall

Write the importance of plasmodesmata.

Which of the following statements is incorrect?

Which of the following is not a function of the cell wall?
$(i)$ Provides shape to the cell.
$(ii)$ Protects the cell from mechanical damage and infection.
$(iii)$ Helps in cell-to-cell interaction.
$(iv)$ Provides a barrier to undesirable macromolecules.