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生物的寿命相差悬殊,通常狗猫等动物寿命只有二三十年;龟类的寿命有几百年;银杏、松柏等树木的寿命可长达数千年,而某些微生物的寿命只有几十秒。人类的寿命随着社会政治经济、自然环境、医疗卫生水平、生活水平等条件的变化而变化。科学上将某一人群预期平均可能存活的年数称作预期寿命,而随着社会的进步与发展,人类的预期寿命普遍在提高。今天医学上对决定人类寿命长短的因素进行了深入研究,其
Biological life expectancy is very different, usually dogs and cats and other animals life is only twenty or thirty years; turtles have hundreds of years of life; ginkgo, pine and other trees can be as long as thousands of years of life, and some microorganisms have only a few life expectancy second. The life expectancy of human beings changes with the changes of social, political and economic conditions, the natural environment, the level of medical and health services, living standards and other conditions. The average number of years in which a population is expected to survive on average is called the life expectancy, and as society progresses and develops, the life expectancy of human beings generally increases. Today, the factors that determine the length of human life are deeply studied in medicine