If there is no sun at night, how can the sunflowers turn back?

Sunflowers follow the sun from east to west during the day, and at night when the sun sets, they slowly turn back from west to east. We all know that sunflowers, from morning to night, turn as the sun moves. But then some people have questions.

The sun rises in the east and sets in the west, and the sunflowers turn from east to west, so when there is no sun at night, will he shake his head to the beginning in an instant? In fact, to solve this problem, we have to understand why sunflowers follow the sun. <>

Plants have a property called phototropism. This is because when the plant is growing, there is a type of auxin in the plant.

Something that can promote the growth of plants, but he is afraid of the sun and always hides in the opposite direction of the sun. Sunflowers also have this substance in their bodies when they grow. When the sun rises in the east, the auxin in the sunflower hides in the west, but once the auxin in the west is too much in the east, it will cause the growth of this side to grow faster, so the plant grows towards the sun.

It seems to us that the sunflower moves with the sun. However, this kind of movement is not timely and has a certain delay. When the sun sets in the west, he will slowly turn back to the east at night, when the sun has just risen.

Wait for the sun to rise again in the east. <>

In fact, not all growth stages of sunflower rotate with the sun, it only rotates with the sun during the period between germination and growth. If the sunflower grows ripe. He will be fixed to the east. <>

The reason why it is fixed to face east and not to the other direction. The main reason is that the sun is scorching at noon, and the pollen of sunflowers is very afraid of the heat. Therefore, facing the east can effectively avoid the direct rays of the scorching sun at noon.

And the flower disc facing east has the advantage of receiving mild sunlight in the morning, killing germs, and has certain benefits for night growth. Therefore, after thousands of years of adaptation to the environment, sunflowers have gradually formed a habit of facing the east.

First of all, it is necessary to understand why the sunflower turns towards the sun, because the sunflower contains somin cells that are protected from light, and these cells have the property of elongation, so they will gather on the side facing away from the sun, and the sunflower will bend in the direction of sunlight after the cells are elongated. In the absence of sunlight at night, these cells do not need to be protected from light, but gather to the west, so the sunflowers turn back.

The sunflower's body regulates itself, and the distribution of auxin changes, and the luteoxi, which inhibits growth, loses its effect, allowing the sunflower to slowly turn back.

After the sun sets, the sunflowers slowly swing back and turn. Of course, not all sunflowers are like this, and mature sunflowers will always be sunny and will not turn anymore.

If there is no sun at night, how can the sunflowers turn back?

The positive nature of sunflowers during the day is mainly due to the presence of auxin in the plant. And at night there is no sun, so the auxin in the sunflower will also help the sunflower adjust its direction and help it turn back.

Only unripe sunflowers behave during the day, and ripe sunflowers are fixed towards the east. And if you look at the unripe sunflowers for 24 hours, you will find that before the sun rises, the sunflower's head is actually hanging on the ground, and as the sun rises, the sunflower will raise its head, and the sun will streak across the sky, and he will gradually turn his head. As the sun sets, the sunflower's head will droop back to the previous night's state, and it will not raise its head again until the first rays of sunlight shine on its head in the morning, and there is no need to shake it back.

In fact, the reason why the sunflower can automatically turn back when there is no sunlight is mainly because the sunflower itself rotates with the sun, mainly because it has growth cells that protect it from light, and these growth cells will automatically adjust the direction of the sunflower at night.

Sunflowers are not a plant that changes with the sun at all times. Generally speaking, it is only when a sunflower blooms that its flower disc rotates with the rotation of the sun. The main reason why sunflowers rotate towards the sun is because there is a substance called auxin in the body of sunflowers.

This auxin can promote the growth of sunflowers to a certain extent, but it is very afraid of sunlight. So whenever the sun rises, these auxins regulate the sunflower's flower disc to help them block out most of the sun's rays. Since auxin often runs to the west side of the sunflower, the west side of the sunflower grows a little faster than the east side.

In the whole way, it will show that the whole sunflower grows towards the sun.

When the sunflower turns to the west with the sun, the auxin in the sunflower will be rearranged after sunset, and the sunflower will be introduced to the east position at 3 o'clock in the morning, and it will rotate with the sun the next day, but when the pot is open, the sunflower will not rotate, and will be fixed in the east position.

Sunflowers have a special habit, that is, they can rotate with the sun, and we are not particularly clear about how the sunflowers turn back with the sun, after the sunflowers turn to the west during the day, in fact, after sunset, the auxin in the sunflowers will be rearranged, and when the sun rises the next day, it has turned to the east.

Botanists have shown that the sunflower pot will gradually swing backwards after sunset, and by 3 o'clock in the morning, the sunflower is already facing east, but when the pot is fully bloomed, it will not rotate with the sun.

Sunflowers follow the rotation of the sun also has certain limitations, in the budding period its auxin is more, can rotate with the sun, but in the later stage, that is, the flowering stage of the sunflower in the auxin gradually decreased, at this time will not rotate with the sun.

The pollen of sunflowers is afraid of high temperatures, and if the temperature is higher than 30 in the environment, it is easy to burn, so it will be fixed in the eastern position, so as to avoid direct sunlight, so the time for the pot to receive light is only in the morning.

Because there is a plant auxin in the stem of the sunflower, this auxin is very afraid of light, and when it encounters sunlight, it will somehow turn itself to the side without light to avoid the sun. As soon as the sun sets, the sunflower disc will silently turn back on its own, and it will turn back to the east at about 3 a.m.

If there is no sun at night, how can the sunflowers turn back?

After the sun sets, auxin is redistributed, and the sunflower slowly turns back to its starting position and stands upright, and in the morning the sun rises in the east and begins to "move" again. However, once the flower disc is in full bloom, it no longer rotates towards the sun, but is fixed towards the east.

It's like an old-fashioned alarm clock, wind it and he'll spin. (The winding is daytime, and the spin is night.) ）

1 All sunflower auxin is formed mainly at the tip of the shoot and transported to the base. The distribution of auxin is affected by light. Bear.

Changsu prefers shady places. Therefore, the stem of the sunflower has more auxin on the side of the sun, and it grows fast and towards.

The sunflower flower disc is facing the sun. I went to look at the sunflowers again, and sure enough, I saw the sunflower with the sun's stem on its back.

The side grows long. But I have another question: since the sunflower disc turns with the sun, when it comes to sunset, it.

It's west-facing. So, how could it be facing east at sunrise the next day? I went to consult with a science teacher.

Only then did I clearly understand that after the sunset, the sunflowers will slowly turn straight by themselves at night, and until the early morning of the next day, too.

Before the sun comes out, it begins to slowly turn to the east to meet the rising sun. Also learned from the science teacher: sunflowers.

It is the seedlings, stems, leaves, and flower disks that rotate with the sun, and the sunflower stems until the flower plate sets seeds.

The products of photosynthesis in the stalk are concentrated in the flower disc at an accelerated pace, the stalk becomes rough and hard, the leaves turn yellow, and chlorophyll.

Fade away, photosynthesis tends to stop, and the flower disc is fixed towards the east and no longer rotates with the daylight.

Mr. Sun said that he would rehearse in the evening and slowly turn back.

Not why