题干

如图所示各曲线所代表的生物学含义及描述正确的是(      )

A:甲图表示人的成熟红细胞中ATP生成速率与氧气浓度的关系

B:乙图中a点表示酵母菌呼吸作用产生ATP最多时的氧气浓度

C:丙图所示物质运输速率不受呼吸酶抑制剂的影响

D:丁图表示小鼠体内酶活性与外界环境温度的关系

上一题 下一题 0.0难度 选择题 更新时间:2019-08-22 09:37:39

答案(点此获取答案解析)

A

同类题3

 Many people believe that yellowing and wetness are the greatest enemy of stamps. In fact, stamps are afraid of not only wetness, but also light and dirty things. People protect their stamps in several different ways.

 To protect stamps,we should never touch the stamps with our hands.This avoids moving dirty things onto them. Stamp tweezers (镊子) should be used in all conditions.

 Stamps are printed things. The colour will slowly disappear if the stamps are put in the light for a long time. So we should not put stamps in the light for long. Direct sunlight must be avoided as well.

 Wetness is an important  problem for stamps. Some  collectors  will put stamps  in separate plastic (塑料) bags. However, it is possible that some stamps have taken in some water from the air before they are put into the plastic bags.Stamps yellow easily and rapidly after they take in wet air.To protect the stamps, some people also put the stamps into a special room which has a machine to  keep the air cool and dry. However, not many people can afford that.

 To keep stamps, stamp collectors usually put them under plastic covers. It is a common and simple way. This helps because the plastic cover keeps the stamps off the wet air. It also stops the fingersfrom touching te stamps.

 Some  collectors  prefer  to  store  stamps  inside  a  plastic  box  with  desiccants  (干燥剂).However, we should take care not to let the stamps. touch the desiccants. On top of that, don't  take your stamps out on a wet day.