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The Liquid of LifeAwake!—2009 | February
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The Liquid of Life
WATER is an enigma. It is both simple and complex. Each molecule comprises just three atoms—two of hydrogen and one of oxygen. Yet, scientists still do not fully understand how water molecules work. What we all know, though, is that water is essential to life, making up about 80 percent by weight of all living things. Consider just five attributes of this amazing substance.
1. Water can store a lot of heat without a substantial rise in temperature, thus helping to moderate climate.
2. Water expands when it freezes, causing ice to float and form an insulating layer. If, like other substances, water became more dense as it froze, the lakes, the rivers, and the seas would solidify from the bottom up, entombing everything in ice!
3. Water is highly transparent, enabling light-dependent organisms to survive at considerable depths.
4. Water molecules produce surface tension, creating an elastic “skin.” This tension enables insects to scamper about on a pond, causes water to form into droplets, and contributes to the capillary effect, which helps water to hydrate the tallest plants.
5. Water is the most efficient solvent known. It is able to carry in solution oxygen, carbon dioxide, salts, minerals, and many other vital substances.
Essential to Earth’s “Air Conditioner”
Oceans cover about 70 percent of the earth, giving them a major role in climate control. Indeed, oceans and atmosphere are practically one, constantly exchanging heat, water, gases, and momentum in the form of wind and waves. They also work together carrying solar heat away from the Tropics toward the poles, thus moderating global temperatures. In fact, for most organisms to survive, temperatures must stay within the range that allows water to remain a liquid. “It appears that Earth got it just right,” says the book Rare Earth—Why Complex Life Is Uncommon in the Universe.
Of course, the earth is an effect, not a cause. But was the cause chance, or was the cause a wise and loving Creator? The Bible says the latter. (Acts 14:15-17) In the following article, we shall see how the Bible’s view is supported by additional evidence—amazing cycles that keep our planet clean and healthy.
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Cycles for LifeAwake!—2009 | February
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Cycles for Life
IF A city’s supply of fresh air and water were cut and its sewers blocked, disease and death would soon follow. Yet, our planet is a closed system—clean air and water are not shipped in from outer space, nor is waste matter rocketed out! So how does earth’s biosphere remain healthy and habitable? The answer: natural cycles, such as the water, carbon, oxygen, and nitrogen cycles, here explained and shown simplified.
The water (hydrologic) cycle involves three stages. 1. Solar power lifts water into the atmosphere by evaporation. 2. Condensation of this purified water produces clouds. 3. Clouds, in turn, form rain, hail, sleet, or snow, which fall to the ground, closing the loop. How much water is thus recycled annually? According to estimates, enough to cover the entire surface of the planet to a depth of more than three feet [100 centimeters].
2
← ◯
↓ 3 ↑
↓ 1 ↑
↓ ↑
→ →
→
The carbon and oxygen cycles involve two key processes—photosynthesis and respiration.a Photosynthesis uses sunlight, carbon dioxide, and water to produce carbohydrates and oxygen. Respiration, which occurs in animals and humans, combines carbohydrates and oxygen to produce energy, carbon dioxide, and water. Thus, the output of one cycle is the input of the other, and it all happens cleanly, efficiently, and quietly.
Oxygen
←
← ←
↓ ↑
↓ ↑
↓ ↑
→ →
→
Carbon dioxide
The nitrogen cycle is essential to the production of amino acids, proteins, and other organic molecules. A. The cycle begins when lightning and bacteria convert atmospheric nitrogen into compounds that can be absorbed by plants. B. Plants, in turn, incorporate these compounds into organic molecules. Animals that eat plants thus also acquire nitrogen. C. When plants and animals die, another family of bacteria break down the nitrogen compounds, releasing nitrogen back into the soil and the atmosphere.
← ← ← ← ← ← ← ← ← ←
↓ ↑
↓ Earth’s atmosphere is ↑
↓ 78 percent nitrogen ↑
↓ ↑
↓ ↓ Organic ↑
↓ A ↓ molecules ↑
↓ Bacteria ↓ B ↑ ↓ C ↑
→ Nitrogen compounds Bacteria →
→ → →
Perfect Recycling!
Consider: Humans, with all their technology, create countless tons of unrecyclable toxic waste annually. Yet, the earth recycles all its wastes perfectly, using ingenious chemical engineering. “Chance processes alone almost certainly could never have duplicated” such environmental harmony, says religion and science writer M. A. Corey.
Giving credit where it is due, the Bible says: “How many your works are, O Jehovah! All of them in wisdom you have made.” (Psalm 104:24) That wisdom has been manifest in a special way toward humankind.
[Footnote]
a The cycles of various chemical elements may combine or overlap. Oxygen, for example, is present in carbon dioxide, carbohydrates, and water. Hence, it shares in both the carbon and the water cycles.
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