题干

阳光穿过森林空隙形成的“光斑”会随太阳移动和枝叶的摆动而移动。右图表示一株生长旺盛的植物在光斑照射前后光合作用过程中吸收CO2和释放O2有关的变化曲线,此曲线说明

A:光斑照射前光合作用无法进行

B:光斑照射开始后,光反应和暗反应迅速同步增加

C:光斑照射后O2释放曲线的变化说明暗反应对光反应有限制作用

D:CO2曲线AB段变化说明进行暗反应与光照无关

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答案(点此获取答案解析)

C

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阅读理解

    When I graduated from college I dreamed of being a television news reporter. Having no experience, I had to work in a small town until I finally got my big break in the form of a job in Boston. I made it.

    Soon, reality set in. I was too often sent to run after accused criminals out of courts, waiting outside of crime scene tape or at the doorstep of a family still crying for tragedy (悲剧). My breaking point came the day I accidentally informed a young woman that her mother died. It was the worst day of my professional life and the day I decided I no longer wanted to shine a light on these stories. My career was ebbing, and at the same time my personal life was too-I divorced.

    My mom had always told me “When you're feeling extremely upset, go help someone else.” So I started seeking out stories of people who had been in the news under tragic circumstances but were doing something inspiring with their lives: a young girl who was paralyzed (瘫痪的) by an accident but was uplifting her classmates with her positive spirit, a blind and autistic (自闭的) musician who learned to play 27 instruments, a disabled soldier who opened his own art studio. I started to tell and promote stories like them.

    Over the last 10 years I have discovered my kindness gift: my ability to see the beautiful side of a person and reflect it back to them and the world. In telling stories of people turning their own hurt into acts of helping others I have become more sympathetic, more grateful and kinder. I have learned kindness is who we are, that our power for it is limitless and that, as we shine a light on it, it grows.