In the Earth there are diverse regions side by side and gardens of grapes and cultivated fields, and palm-trees sharing one root and others with individual roots, all watered with the same water. And We make some things better to eat than others. There are signs in that for people who use their intellect. (Qur’an, 13:4)As described in the previous section, the first phase of development of a seed into a plant is its transportation. Then the germination begins. When a seed has matured, it usually does not germinate immediately, for in order to germinate, several different factors must come together at the same time. The right levels of heat, moisture and oxygen are necessary. If any one of these conditions is missing, the germination process stops. But when all these conditions are present, the quiescent seed comes to life.
| In a fresh seed, the nutrient reserve is a rich, moist gel surrounding the embryo. As the seed dries, it hardens into a shape suitable for storage, and the nutrient reserve hardens too. Later, when the seed is moistened, the nutrient turns back into a liquid gel that nourishes the roots and stem until it sprouts leaves that can feed the plant. This process is easily observed in sweet corn, which is soft when fresh, but the corn hardens as it dries out. As fresh corn dries, its sugar turns into starch. But when moistened, this starch turns back into sugar. The seed needs water to undergo this chemical change. |
At this stage, oxygen becomes imperative. With respiration, the seed starts to produce from the nutrients it contains the heat and energy it needs to form new parts of the growing plant. The appropriate temperature, on the other hand, enables the enzymes to function at maximum speed.52
Nutrients are required for the seed to grow, but it doesn’t yet have a source it can draw on until it is ready to take in minerals through its roots. So how does the seed find the nutrients it needs to develop?
The answer to this question is hidden inside the seed. As has been detailed in previous sections, the reserve of nutrients that develops during the pollination process is used by the seed until its shoot emerges out of the earth. Until seedlings grow leaves capable of making their own food supply and roots to absorb nutrients from the soil, they are dependent on these nutrients stored within their structure.
(a) When the seed absorbs water, gibberellin (GA), a growth-regulating hormone, is released from embryo into endosperm. (b) Production of digestive enzymes begins. (c) Enzymes break down starch and other molecules in endosperm, releasing soluble nutrients, which the cotyledon absorbs. (d) The absorbed nutrients are delivered to the shoot and root. The first foliage leaf emerges. (e) By the time storage reserves are depleted, the first foliage leaf has expanded and begun photosynthesis. (Solomon, Berg, Martin, Villie, Biology, p. 768.) |
When the seed starts germinating, it draws water from the earth, and the embryo cells start dividing. Then the seed coat opens. Little roots, the first outward sign of the plant’s root system, emerge and grow down into the earth. As the roots grow bigger, the earth starts to restrict them. But although subjected to extreme pressure, they are not damaged, since the newly forming cells at the tips of the roots are constantly active and provide protection as the root moves through the hard earth particles. The cells behind this protective layer (calyptra) have the ability to divide very swiftly and let the root grow by up to 11 cm a day. The roots branch as they develop, providing a greater surface area to take in water, while serving to anchor the plant more firmly in the earth. In addition, the tiny root hairs play an important role in increasing the plant’s capacity to draw essential minerals from the earth.54
Due to the stimulation of gravity, a plant’s roots grow quickly down into the earth. The tips of the roots are formed from the meristem tissue, which is capable of swift division for growth. This tissue is protected by a cap (calyptra) consisting of parenchyma cells that produce a substance called mucilage, easing the passage of the roots into the earth while speeding up the absorption of certain ions from the earth. New cells formed by the division of the meristem tissue allow the roots to lengthen. In addition, these cells diversify as they mature, taking on the roles of transportation, storage or epidermal cells, depending on their location. (Ozet, Arpacı, Biology 3, p. 48.) |
What we have explained so far is common knowledge. Everyone has observed seeds come up. But in reality, a miracle happens when a seed weighing only a few grams has no difficulty in pushing its way up through a great weight of soil. The seed’s only aim is to reach the sunlight above. It is as though the slender stems of newly germinating plants are moving freely in an empty space rather than gradually making their way through something heavy, towards the light of day.
Trials have been conducted into blocking the seed’s access to the light by various means, with really surprising results. The seed manages to get to the light by putting out long shoots around obstacles in its path or by applying pressure from its growing tip. A seed’s sense of direction and determination to reach the light can be understood more easily by watching a time-lapse film version of its germination.
Since germinating seeds aim to reach the light, seedlings always move with the intent of surfacing above the soil. But a germinating seed’s growth takes place in two directions. While the sprout grows upwards, against gravity, the taproot delves down into the earth.
It’s really thought-provoking that two portions of the same plant can grow in completely opposite directions. How do both the sprout and roots know which direction to grow in?
The stimuli that direct a plant’s growth are light and gravity. In the emerging roots of a germinating seed are cells that can sense gravity, and there are light-sensitive cells in the upward-growing shoot. Due to these cells’ sensitivity, parts of the plant are guided in the right direction. These two guidance systems also ensure that if the roots and the shoot must progress in a horizontal direction, their direction is corrected as soon as possible.55
There is another interesting aspect to germinating seeds. Soil bacteria have the capacity to rot and break down organic matter, yet seeds and roots no more than half a millimeter in breadth are not damaged at all. On the contrary, they use the soil to maintain constant development and growth.
During germination, rapid cell division takes place, accompanied by rapid and increased absorption of water. Germination releases an energy against the normal air pressure. This energy is so powerful that it is equivalent to approximately 100 times air pressure. This gives young shoots the power to crack rocks and walls made of concrete. (Grains de Vie, p. 82.) |
To questions like these, there is only one answer. Naturally the plant itself doesn’t make and implement these decisions, or set up the systems necessary to avoid confusion. Nor are the cells that compose the plant able to do this. A cell can’t predict and decide, or consciously perceive light or gravity. Even with the intervention of another living being such intelligent systems could not be developed. For instance, if told to create a plant cell sensitive to gravity, even the world’s foremost botanist could not perform such a task.
Nothing can stop seeds from reaching the light of day. As they grow, plants can exert great pressure. For instance, some seedlings can extend the cracks in a newly made road. |
During germination, roots grow down into the soil while the shoot grows up into the sunlight. |
We sent down a measured amount of water from heaven and lodged it firmly in the earth; and We are well able to remove it. By means of it We produce gardens of dates and grapes for you, in which there are many fruits for you and from which you eat. (Qur’an, 23:18-19)
Stages of germination in the hyacinth. In all the germinating plants in the world, these processes are carried out to perfection. All hormones and enzymes are secreted without omission, or else germination could not take place. Accordingly it’s not possible to claim that germination is coincidental. Every stage of the process occurs with the knowledge, and under the control, of God. |
The seedling in the picture below will in time grow into a great oak tree, as in the picture to the right. |
The source of this force is the hydraulic pressure that builds up inside every plant’s cells. These pressures, essential for the plant’s growth, stretch the cell walls. Were it not for this effect, cell enlargement in the plant would not be possible, and seeds would not be able to germinate.56
After using such force to emerge from the soil, the seedling does not always find an appropriate environment. As already explained, if any object blocks the sunlight, the plant has difficulty in photosynthesizing and consequently cannot grow. For this reason, every emerging shoot will bend toward light as soon as it reaches the surface. This process is called phototropism, the light-sensitive direction-finding system in plants.57
The sunflower is one of the best examples of plants that turn toward the sun. Above: The movements of a sunflower throughout one day as it follows the sun. |
Germination is the first stage in the development of a tiny plant that can grow to be meters in height and tons in weight. As it grows and its roots extend into the ground and its branches into the air, its internal systems (alimentary, pollination, the hormones that regulate and halt the plant’s growth) all operate simultaneously, with no hitch or delay in any of them. Everything the plant needs develops at the same time – a very important detail. For instance, while the plant’s pollination system is developing, so is its distribution network of nutrient and water channels. Otherwise, if a tree’s pollination system failed to develop, its inner bark used to carry water and nutrients would have no significance. And there would also be no point in the roots’ development, since the ancillary mechanisms would have no function given that the species would not survive.
However, there are no such hitches. Everything develops just the way it should, and at the time it should.
As the shoot breaks through the seed coat, it accomplishes a very difficult task. A soft little shoot has no problem bursting free from the confines of the tough seed coat of a cherry or hazelnut, that we can manage to break only with a hard blow. The task is made easier by such factors as the softening of the seed coat when the seed takes in water and increased pressure inside the seed. It is God Who creates them together with these features. |
The perfect order in the processes that we’ve examined here is evidence of a Creator Who accomplishes every minute detail. Even the formation of the seed, the very first stage of plant life, is enough to demonstrate the incomparable wonder of God’s creation.
When the seeds protected inside the pinecones at left reach the ground, the germination processes are set in motion. From these little seeds, magnificent pine trees will eventually grow. |
Examples of the seedlings of various plants. Day by day, these feeble little shoots will grow into great trees – an incredible change brought about by the knowledge that God installs in seeds. | The transformation of little shoots that grow up through cracks in the soil into great trees illustrates many points for those who use their intelligence. All thoughtful people can see God’s magnificent art everywhere they look |
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