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| The arm works like a lever. The supporting pivot is the elbow, about which the muscles facilitate movement through contractions and flexions. Excavators also work on the same principles. While the excavator exerts the same force under all loads, the muscles of the arm control the intensity of forces. | The cell is a very energy efficient engine. It consumes small molecules called ATP for fuel. Its efficiency in burning this fuel is much greater than any other engine known to mankind. In addition, the cell simultaneously performs a diverse variety of tasks, such as no manmade device can handle. |
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| Each neuron cell contains units that are only responsible for transferring information. A single brain can process work equivalent to that of 4.5 million transistors on a modern microprocessor. The millions becomes insignificant in comparison with ten billion, highly capable neurons transmitting information in the brain. In addition, there is not a single industrial product that can imitate the faculties of taste and smell in the brain. | The minute hairs in the inner ear of a human convert sounds into electric signals just as do a microphone. The ear can only sense sounds between the frequencies of 20-20,000 Hz. This spectrum is ideal for humans. If the human were to have a larger spectrum, we would hear sounds from the footsteps of an ant to high frequency sound waves in the atmosphere. This situation would not have been comfortable for humans at all, due to the presence of a continuous noise. |
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| The human kidneys filtering units about 37 gallons (140 litres) of blood everyday, through one million small filtering units called nephrons, and that continues for about eighty years without rest. Refinery pants designed for industrial wastes can hold much greater quantities, but their lifespan is considerably less. Furthermore, the chemical composition of the substances they filter are much less complicated in comparison to blood. A kidney is far more complex and efficient than any refinery plant | Muscle movements contribute to warming up of the body in cold weather. Muscles can provide up to 90% of body heat in this way. Perspiration, on the other hand, functions as the ideal cooling mechanism against overheating. These two balancing systems work together to maintain a steady body temperature. This system works much more swiftly and with more precision than any other air conditioning system. |
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| There are two main possible outcomes for any system receiving impacts. It will either cause a dent or cause some parts to break away. The skeletons of creatures and the chassis of the car have been designed to minimise the impacts on the bodies. However, the chassis lacks the ability of bones to repair themselves. | Our organisms are defended by roughly 200 billion white blood cells. Just like soldiers, these blood cells have an intelligence system, lethal weaponry and special battle strategies. However, no other army on earth is as punctual, perfect and successful as the immune system. | Everything in the body is in a state of communication. Many messages are in the form of hormones composed of large molecules. There is no receiver on the packages of messages carried by the hormones that freely wander in the circulatory system and among the neurons. However, the package always gets to its place because the organs receiving the messages are equipped with special sensors. |
