Question

Pit membrane consists of

• A. Primary wall
• B. Middle lamella
• C. Middle lamella + Primary wall
• D. Primary wall + Middle lamella + Primary wall

Answer 1

Answer: (D)

Primary wall + Middle lamella + Primary wall

• The lignified depressions in the secondary cell wall form a pit.
• Each pit consists of complementary pit opposite the neighbouring cells and the complementary pits are known as pit pairs.
  
• Pits are consists of three parts-

1. pit chamber is the hollow area where the secondary layers of the cell wall are absent.
   
2. pit aperture is an opening at both the end of the pit chamber.
   

pit membrane is a primary cell wall (one cell), middle lamella and primary cell wall (second cell) or the membranes between the adjacent cell walls at the middle of the pit chamber.

• So,' Primary wall + middle lamella + Primary wall'.