Descartes, a famous mathematician, studied the curves of petals and leaves and found the famous "Descartes curve" in modern mathematics. Symmetrical radiation of flowers and spiral arrangement of fruits conform to the golden section law in mathematics. The tillers of wheat are arranged around the cylindrical stems according to the golden section. The leaf shapes of common clover and ivy can also be expressed by trigonometric function equation.
Taking leaves as an example, the arrangement of leaves is based on getting enough photosynthesis area and collecting more sunlight. For example, banana leaves are arranged in rotation, and the angle between leaves is137 30', which is the golden ratio of a circle. The same is true for pear trees. The arrangement of leaves rises along a logarithmic spiral, which also ensures that the leaves do not overlap, and the lower leaves are just from above.
The stems of higher plants also have the best shape. The thickness of the mechanical tissue of many herbs is close to one seventh of the diameter of the stem. This cylindrical structure is very suitable for engineering to obtain maximum robustness with the least material consumption. Some four-sided stems have mechanical tissues distributed in the four corners, which also improves the supporting ability of the stems and supports a larger leaf area.
Of course, the spatial arrangement of the whole plant must conform to the principles of mathematics and mechanics in order to adapt to the survival and development of nature. Like some big trees, they all have inclined and nearly vertical branches, cylindrical stems and multi-branched roots, which are conducive to growing more leaves, occupying more space and better photosynthesis.
Through the lush foliage, we see the mathematical wonders in the green world. If we further understand the mystery and bionics, it will bring infinite benefits to mankind.
1. Summarize the center of this article with the sentences in the original text.
A: Although plants have countless postures, whether they are flowers,
The distribution of leaves and branches is very symmetrical.
Balance and coordination.
If we answer the spatial structure of plant morphology, it contains both biological beauty and mathematical beauty. )
2.① Underline the sentence?
② The structural features of the third paragraph are as follows
(Total score)
3. "Many flowers are almost completely symmetrical." Can the word "almost" be deleted from the sentence? Please provide a justification for the answer.
A: It cannot be deleted. Because the word "almost" means that not all flowers are completely symmetrical.
The word "almost" embodies the accuracy and reliability of the explanatory text.