题干

将一植物放在密闭的玻璃罩内,置于室外进行培养,假定玻璃罩内植物的生理状态与自然环境中相同。用CO2浓度测定仪测得了该玻璃罩内CO2浓度的变化情况,绘制成如图的曲线,下列有关说法正确的是

A:H点CO2浓度最低,说明此时植物对CO2的吸收量多,光合作用最强

B:CO2浓度下降从DE段开始,说明植物进行光合作用是从D点开始的

C:D点表明植物光合作用强度和细胞呼吸强度相等

D:D点较B点CO2浓度高,是因为D点温度高,使植物细胞呼吸强

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答案(点此获取答案解析)

C

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    Open work spaces definitely have their benefits,but they come with the drawback of offering employees little to no control over visual distractions(干扰).With so many people around and so much going on,some of us can easily get disturbed by this information overload and lose focus in what's really important.That's where the Focus Cap comes into play.

    “As we are still cavemen or mammals kept in an unnatural environment,I believe that only by reclaiming(收回)the normal,stress-free human state through simple tools and techniques can we finally release our actual creative potential and create our meaningful work for a brighter future,”says German designer Hannes Greblin,inventor of the Focus Cap.

    After looking at other products designed at minimizing visual distractions,Greblin decided that most of them were either too expensive or too uncomfortable to become mainstream,so he decided to go with something much simpler —a simple cap with a retractable visor(可伸缩的帽沿).

    Greblin's Focus Cap is really straightforward.You just wear it like a regular cap'with the sides of the visor retracted,and just collapse the sides whenever you need to focus on what's ahead of you.Whether you're trying to focus on a task in an open work office.Trying to study at university,or practicing yoga in a park and trying to ignore stares from strangers,the Focus Cap can help.

    To be honest,this whole project sounds like a joke,but the Focus Cap does have its own website where people interested in this unusual accessory can actually sign up for updates on when it will go on sale.Greblin claims it will cost 30 euros($37)plus shipping.