Have you ever seen a field of sunflowers? The brilliant yellow flowers, swaying together in the wind are enough to take anyone’s breath away! Sunflowers have the tendency to face the sun all through the day; and that is why, they are called by that name.
The ability of the flower to follow the movement of the sun is called phototropism, which literally means ‘moving along light’. Many flowers have this ability. A hormone named Indole Ascetic Acid regulates this movement in the plants. This hormone moves through the body of the plant and can regulate cell growth and enlargement of the part wherever it is located.
In the morning, the hormone moves to the west side of the plant where sunlight does not fall and causes the stem of the flower to stretch to the eastern direction. In the afternoon, the plant appears to be following the sun throughout the day. During night, however, the hormone spreads through the body of the plant and does not concentrate on a particular location.
Sunflowers have many uses for Man. The oil extracted from the seeds of the flower is used for cooking. The seeds are also used as a delicious snack.
Picture Credit : Google