The dandelion's petals can open and close because they are photosynthesizing, which is also known as "sleep movement" by some botanists.

The opening and closing of dandelion petals is related to light and darkness, temperature and air humidity. During the day, when there is light, dandelion petals open slowly to get the nutrients they need to grow.

If there is not enough light in the morning, the petals will be unopened. At night the dandelion florets rise upwards and close into a respiratory state, with the aim of reducing water evaporation.

All in all, the dandelion petals open and close with people and animals, are a self-protection instinct, is for their own better survival and development.

Expanded information:

Dandelion is a perennial rooted plant, wild conditions, two-year-old plants can bloom seeds, early summer for the number of blooms and knots with the number of years of growth and increase. Some single plants have more than 20 flowers, and the number of flowers on a single plant of a good variety can be as high as 20 or more, and the seeds mature after 13 to 15 days after flowering.

The characteristics of dandelion are:

1, dandelion root is a little like cone-shaped, a little curved, the length is about 4 to 10 centimeters.

2, its surface is tan in color and the root head has brown or yellowish-white hairy tufts.

3, Dandelion's leaves are obovate-lanceolate or oblanceolate or oblong-lanceolate, with margins sometimes undulate-toothed or pinnately parted.

4, dandelion scape has one or more, the upper part of the flower is purple-red, densely long arachnoid white villous.

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