人到老年,老态龙钟就显而易见:白发,秃顶,视力衰退,力气减少,皮肤出现皱纹,骨头日益脆弱。可是,人为什么会衰老呢? 衰老并非是一切生物命中注定的事。实际上,在地球上的生物进化过程中,衰老是较晚出现的。细菌就生来不会衰老和死亡,只要不发生意外事故,这种简单的单细胞生物可以无限地分裂和繁殖下去。我们不禁会想,人类终有一天会懂得如何效法细菌——至少可以多活好几年。这种延年益寿当然令 People to old age, old age is obvious: white hair, baldness, vision loss, strength reduction, skin wrinkles, increasingly fragile bones. However, why people aging? Aging is not all creatures destined to do. In fact, aging occurs later in the biological evolution on Earth. Bacteria are born without aging and death. As long as no accidents happen, the simple unicellular organisms can divide and multiply indefinitely. We can not help wondering how one day humans will know how to follow the bacteria - at least for years. Of course, this longevity