Question

Tyloses are balloon-like in growths in vessels developing from adjoining

• A. Parenchyma through pits in vessel wall
• B. Parenchyma thorugh general surface of vessel wall
• C. Fibres through general surface of vessel wall
• D. Fibres through pits on vessel wall

Answer 1

Answer: (A)

Parenchyma through pits in vessel wall

The balloon shaped intrusions appear in the xylem vessels of heart wood or duramen are called Tyloses. These are formed by the intrusions of ray parenchyma through pits present in the cell wall of vessels. In this cell walls are lignified. They block the xylem vessels. Due to the presence of tyloses, Pathogenic organisms cannot infect the heart wood due to the presence of tyloses.

So, the correct answer is 'Parenchyma through pits in vessel wall'.