Why is the lotus root broken

"Lotus root is broken and connected", which is almost a well-known idiom. It refers to a seemingly broken relationship, but in fact there are still countless ties of concern. This idiom comes from a well-known natural phenomenon, that is, when the fresh lotus root is broken, although the main body has been completely separated, there are still many filaments connected at the broken place. Why can these filaments have so much ductility?

If we put the filament under the microscope, we can find the mystery. It turns out that each lotus root silk that we can see with the naked eye is not cylindrical, but flat. It is composed of 3 ~ 8 finer filaments. Interestingly, each thinner wire is coiled like a spring and has great flexibility. If our hands can become small enough, as long as we hold both ends of the filament, we can stretch it hard and shorten it when we let go.

So, what is the structure of tenacious filaments? Botanists tell us that it is a transportation system called conduit, which is specially used to transport water and inorganic salts dissolved in water. Sometimes, the inner wall of the vessel of plants will be particularly thickened in some parts, showing various textures, such as circular trapezoid, and some are net shaped.

The vessel wall of lotus root is very special, and the thickened part is continuously spiral, that is, the spiral vessel in botanical terminology. Once the lotus root is broken, the thickened spiral part of the inner wall of the catheter will separate and form spiral filaments with a diameter of only a few microns. Under the action of external force, these filaments will become elongated "micro springs", which will not be broken within a certain elastic limit, and their limit length can reach about 10cm. In fact, there are filaments not only in the lotus root, but also in other parts of the lotus, such as leaves, petioles, pedicels, petals, lotus canopy, etc. after breaking, there are filaments connected, but some filaments are extremely small and can not be compared with the lotus root.

The phenomenon of broken lotus roots can not help but remind people of a valuable medicinal plant - Eucommia ulmoides. Many people have tried to break the bark and even leaves of Eucommia ulmoides, there will be countless strong white silk, showing the state of "skin broken silk connection" or "leaf broken silk connection". Although it has a similar form of expression with lotus root, the internal reasons are completely different.

The filaments of Eucommia ulmoides are not ductal tissue, but the milk inside. Because there are many milk tubes in the bark of Eucommia ulmoides, which can secrete white cell fluid. Because this cell fluid contains more rubber components, it is called Eucommia ulmoides gum. After the bark of Eucommia ulmoides is broken, the rubber wire is connected between the two sections. We know that the rubber wire is full of toughness, a bit like our usual rubber band, so even if the bark is torn, the rubber wire inside needs to be pulled hard to break.