老师
各位同学，大家好，我是中国人民大学附属中学的生物老师梁慧媛。今天我讲授的课程是初中生物学七年级上册光合作用吸收二氧化碳释放氧气的第2克时。通过上节课的学习，我们了解了光合作用的发现历程，归纳出光合作用的概念和反应，解释这节课我们将学习光合作用在生物圈中的意义，在农业生产中的应用，并完成相关的拓展练习。请大家准备好本节课的任务单，请观看一段科普视频，体会绿色植物光合作用释放氧气的强大能力。
学生
But oxygen that complex life like us can operate at for long. So at the top is your heart rate. How is that really high? I think it might be a little bit anxious about going in there. I'm sure. Your resting heart race not normally 92. No, I have been thinking a lot about it. My vital signs have been monitored along with the oxygen levels in my blood.
学生
Now it's time to be sealed inside the chamber for the next 48 hours. I was ready to let it be a guy. So can we open this door? Wish me luck. Oh, I small wasn't that.
学生
Oxygen levels in the air are normally 21%. Inside the chamber, they're far lower, just over 12%. At these concentrations, the cellular activity in my body and brain is starting to slow. Crucial step is to see if the 300 plants in here with me can produce enough oxygen 查看隐藏内容