Question

As secondary growth proceeds, in a dicot stem, the thickness of

• A. Sapwood increases
• B. Heartwood increases
• C. Both sapwood and heartwood increases
• D. Both sapwood and heartwood remains the same

Answer 1

Answer: (C)

Both sapwood and heartwood increases

The increase in lateral thickening is called as secondary thickening or secondary growth. This development takes place in stele (intrastelar secondary growth) and also in the cortex (extra stellar secondary growth). The elements of secondary xylem constitute wood. The xylem includes heartwood and sapwood. Hence, during secondary growth, both the sapwood and the heartwood increase in thickness.

Thus, the correct answer is option C.