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Do cacti have leaves? Detailed answer Directory / Big encyclopedia. Questions for quiz and self-education Did you know? Do cacti have leaves? The cactus is able to grow in harsh conditions because this plant has adapted to such conditions. Cacti have the same structure and development as other plants. But the work that leaves do in most other plants is done by stems and branches in cacti. The absence of leaves and the presence of thorny branches and stems help cacti survive in hot and dry areas. The leaves of other plants are thin and have pores through which the plant breathes. During cell division and the formation of new ones, water is released through these gusts of air. The cactus must save every drop of water. Therefore, the function of the leaves is taken over by the stems and branches. There are few pores in their thick skin, and water is retained in the cactus. The roots of cacti are located close to the surface of the earth. Therefore, cacti quickly absorb water from the surface after rain. This water that passes through the roots accumulates in the fleshy or hollow stems of the cactus. The outer coat of the plant is thick and smooth, and this also helps retain water. The outer cover of the cactus is sinewy. In some cacti, the veins tighten and stretch like an accordion. They stretch when filled with water and shrink when the water is used up. In the cactus family, there are specimens that have leaves, such as the lemon vine in western India. But in most cacti, the leaves have turned into spines, bristles or hairs. This helps cacti protect themselves from animals that would otherwise eat them, as they may be the only green plants in the area. Author: Likum A. Random interesting fact from the Great Encyclopedia: What is radio astronomy? In 1931, a communications engineer at Bell Laboratories was investigating atmospheric radio interference that could affect transoceanic telephone communications. He caught some noises, clearly not coming from a thundercloud, but from somewhere in space. He discovered that it is possible to receive radiation from the galaxy. Thus was born a new branch of astronomy - radio astronomy. Radio astronomy is developing in two directions. With the help of special antennas, it is possible to capture the radiation of space objects. This may be thermal radiation (radiation of radio waves emitted by any hot body). But there are also noises, or static interference of cosmic origin, also picked up from space, but not at all thermal in origin. Another branch of radio astronomy is sending signals to objects such as meteors and the Moon and picking up their reflections. This is how radar works. Radio astronomy is most useful for studying the Sun, meteors, the Moon, and the planets of the solar system. By capturing the reflection of rays from meteors, we learn a lot about their orbits. Exploring the moon using radio astronomy techniques, we learn a lot about its surface. So, even before people set foot on the moon, thanks to radio astronomy data, scientists already knew that its surface is a rock crushed into dust. Probably one of the most exciting areas of radio astronomy is the search for signals from other worlds. Now radio telescopes have been improved to the point where they can pick up signals coming from a distance of almost eighty trillion kilometers. What signals are scientists hoping to pick up? It is believed that if somewhere in deep space there is a civilization other than ours, and it wants to make its presence known, then our brothers in mind will probably send some very simple signal, such as a series of numbers. It is also believed that these signals are likely to be received at a purity of 1420 MHz - the frequency at which simple hydrogen emits radiation waves in outer space.
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