If you do any flower gardening, you know that plants frequently turn or grow towards sunlight. How they know where the sunlight is, and how the plant turns toward that sunlight, are examples of incredible chemical design.

Cells communicate through a language of chemical signals. Compounds such as hormones and neurotransmitters act like words and phrases in telling a plant what to do. In our bodies, for example, our pancreas detects the presence of food that has just been eaten. When this happens it releases insulin, a hormone, to tell other cells in the body to remove glucose from the blood. Just like we need ears to hear communication from a mouth, cells also need “ears.” For plants, the ears are receptor proteins located on the cell wall. They hear all of the chemical symbols coming from a variety of sources and respond to the ones designed into the plant. That is like us hearing 50 people talking to us all at once, and picking out the one we really need to hear.

In the case of plants turning toward sunlight, it is the tips of plants that do the “listening.” These tips of plants produce auxin — a hormone that tells cells to grow and divide. The less sun the tips get, the more auxin they produce. That means that the cells on the shady side of the plant get more auxin, and their cells grow more than the sunny side of the plant. When the shady side grows more, the plant will bend toward the sunlight.

It may seem to be a simple thing for a plant to grow towards sunlight, but the mechanics behind this simple act of survival demonstrates incredible wisdom and planning. Each chemical has to be carefully designed, and the chemistry of the receptor cells and their method of emitting signals are incredibly complex. The more complexity we see, the more we can wonder at the intelligence involved. We can know there is a God “through the things he has made” (Romans 1:20). Source: Discover, October 2013, page 12.

Picture credits:
http://en.wikipedia.org/wiki/File:Iglesia_de_Nuestra_Señora_de_La_Blanca,_Cardejón,_España,_2012-09-01,_DD_02.JPG.