The "silk" of "broken silk" is lotus root silk, which is a spiral catheter formed by the continuous thickening of the catheter wall of lotus root. When the lotus root breaks, the spiral part of the inner wall of the catheter is separated and becomes a spiral filament with a diameter of only 3 ~ 5 microns. These filaments are much like stretched springs, and will not break within the elastic limit, and can generally be stretched to about 65,438+00 cm.

Lotus root silk not only exists in lotus root, but also exists in lotus root stem and lotus root, but is thinner.

I. Nutrition Organization

Vegetative tissues have thin cell walls and large vacuoles, which can store nutrients, and vegetative tissues containing chloroplasts can also carry out photosynthesis. So, A is wrong.

B. Protection organizations

The protective tissue of plants is generally composed of epidermal cells on the surface of roots, stems and leaves, which has the function of protecting internal tender parts.

So b is wrong.

C, meristem

The cells that make up meristem are small, thin in cell wall, large in nucleus and thick in cytoplasm, and have strong ability to divide, and constantly divide to produce new cells to form other tissues. So, C is wrong.

D, transportation organization

Catheters in plants can transport water and inorganic salts, and sieve tubes can transport organic matter, which belongs to transport organizations. Therefore, d is correct.

So choose d