How do plants without mouths "eat" nutrients?

Do plants also have mouths? Of course, if plants don't have mouths, how can a tiny seed grow into a towering tree? Why can't we see it? One reason is that the mouths of plants are very delicate, thousands or even hundreds of times smaller than the mouth of a cherry. Another reason is that the mouths of plants are hidden underground, so they are naturally difficult to see.

In 1648, Belgian scientist Helmont planted a 2.5 kg willow sapling in a wooden barrel filled with soil that had been weighed in advance. After that, he only used pure rainwater to water the sapling, and he also made a special barrel cover to prevent dust from falling in. Five years later, the willow tree gradually grew. After weighing it, he was surprised to find that the weight of the willow tree increased by more than 80 kg, while the weight of the soil decreased by less than 100 grams.

So where did the 100 grams of soil go? Obviously, it was eaten by plants for their own growth.

The roots of plants live in the soil. Plants rely on roots to eat. So which part of the roots do they mainly rely on for food? Plants rely on the root hairs in the root hair zone to eat.

Root hairs are a special structure produced by the outer layer of cells in the root hair zone, namely the epidermal cells. They are produced by the outward protrusions of the epidermal cells at the tip of the young root.

What do root hairs look like? If you look at them under a microscope, they look like closed bottles sticking out from the outer wall of a cell.

The length of root hairs ranges from 0.15 mm to 1 cm, and the diameter is a few hundredths of a millimeter. The absorption epidermis that forms the root hairs is covered with a layer of sticky substances that can glue the root hairs and the soil together. This is because the root hair walls of many plants contain a kind of colloid, so if a seedling is pulled out of the soil, you will often see clods of soil tightly wrapped by the root hairs.

So, how many root hairs are there on the roots of plants? There are a lot, hundreds of them per square millimeter, and some can have more than 2,000 root hairs.

Each root hair is equivalent to a mouth. This mouth has a strange shape, so the way it eats is also special.

Generally speaking, a corn plant consumes more than 400 kilograms of water from germination to fruiting; to produce 1 ton of wheat grains, the plant needs more than 1,000 tons of water. So how does water enter the plant?

Plants rely on roots, or more precisely, root hairs, to suck water from the soil like a straw, but this is not quite the same as a baby sucking breast milk, because the power of a baby's sucking comes from the baby itself, and the power of root hair sucking comes from two aspects: when there is a difference between the concentration of cell sap in the roots and the concentration of water in the soil, and the concentration of cell sap must be greater than the concentration of soil solution, the root hairs can smoothly absorb water into the cells and into the plant body, otherwise the opposite will occur. While the plant body obtains water, it also obtains inorganic salts and organic matter dissolved in the water to ensure the needs of plant life activities.

Look, the way of eating with a strange mouth is of course unique. It relies on the power of concentration difference or the power of root pressure to absorb water into the body.