普特英语听力：为什么要接吻
对于接吻你怎么看?你曾经有过疑惑，为什么要接吻?下面，我们来听一篇听力，听听那些接吻的理由。更多精彩内容请继续关注应届毕业生考试网。
People kiss for the simple reason that it feels good. Our lips are full of sensitive nerve endings, which activate sensory areas in the brain. Kissing boosts the levels of neurotransmitter substances such as dopamine, serotonin, and oxytocin. Dopamine triggers craving and desire, serotonin elevates a person’s mood, and oxytocin is involved in forming emotional attachments.
Besides humans, the only animals that scientists have ever seen kissing are our closest ape relatives, chimpanzees, and bonobos, and even then it is a rare occurrence. So scientist think there must be a better explanation for it.
Kiss and Tell
Some scientists have theorized that kissing might help us assess a partner’s immune system. When people kiss, they come close enough to sample the scent of each other’s bodies. And that scent may contain clues to immune system compatibility.
Parents with complementary immune systems have children with a stronger ability to resist disease. Children that are better at resisting disease are more likely to survive to have their own children. Evolution will favor those who choose partners with compatible immune systems over those who don’t, even if they don’t even know that they are doing it.
Exchanging saliva may provide other chemical clues to genetic compatibility too. So, kissing really is all about chemistry!
人们接吻的原因很简单，就是它会让你感觉良好。我们的嘴唇布满了神经末梢，这些神经末梢连接着大脑相应的神经区域。接吻使一些神经递质物质迅速增加，例如多巴胺，血清素以及催产素。多巴胺触发人们的欲望，血清素能使人们情绪激昂，催产素会对情绪的'变化有影响。
除了人类，科学家发现唯一有接吻行为的动物，就是我们的近亲，黑猩猩和倭黑猩猩，即使在它们之中这种现象也极少发生。所以科学家们认为人类要接吻还有更好的理由。
亲吻和诉说
有科学家认为接吻可以获取对方免疫系统的信息。当人们接吻时，相互间足够近的距离使他们可以感受到对方的气味，这些气味中包含着免疫系统兼容性的线索。
具有互补性免疫系统父母的孩子更容易抵抗疾病。而这些抵抗疾病更强的孩子也能更好的生存下来并孕育健康的下一代。进化过程更加偏向那些具有兼容性免疫系统的伴侣，即使他们也不知道为什么会在一起。交换唾液或许也提供了基因兼容所需的其它化学物质的一些线索。所以接吻真是一场化学反应。
【普特英语听力：为什么要接吻】相关文章：
普特英语听力短文08-19
普特英语听力短文《移动的手指》08-19
人类为什么不能穿墙「普特听力文摘」08-19
普特听力短文：切洋葱为什么会流泪08-19
为什么要学习PHP?09-26
为什么要考税务师09-07
组装电脑为什么要选固态硬盘10-04
提高英语听力的方法是要多听11-10
汇编调用c函数为什么要设置栈09-30
为什么要推行办公自动化10-04