题干

图甲所示为物质出入细胞膜的示意图,乙所示为出入方式与浓度的关系,请回答问题.

(1)图甲中A代表____ 分子;B代表____ 

(2)细胞膜从功能上来说,它是一层____ 膜.

(3)动物细胞吸水膨胀时B的厚度变小,这说明B在结构上具有____ 

(4)若图甲是癌细胞的细胞膜,则膜上含量较正常细胞减小的物质是____ 

(5)在a~e的五种过程中,代表被动运输的是____ ,它们可用图乙中的①表示的是____ ,可用图乙中②表示的为a~e中的____ .

(6)性激素进入小肠上皮细胞应是图中编号____ ;葡萄糖从肠腔进入小肠上皮细胞的过程是图中编号____

上一题 下一题 0.0难度 选择题 更新时间:2019-11-08 14:47:53

答案(点此获取答案解析)

蛋白质,磷脂双分子层,选择透过性膜,流动性,糖蛋白,bcd,b,a,b,a

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    Early birds-people who feel most energetic in the morning-tend to make healthier food choices throughout the day than night owls(夜猫子) , according to a new study.

    "Evening types had more irregular meal times," notes study author Mirkka Maukonen, studying human nutrition and obesity(肥胖) in Finland.

    Her study focused on people's risk of heart disease and their eating habits. Participants described when and what they had eaten during the past two days.

Maukonen's team then looked at l,854 people's lifestyle. After analyzing the data, the researchers found that both morning and evening people consumed approximately the same number of calories over a whole day.  However, night owls tended to eat their meals later than early birds. Before 10:00 am, night owls consumed less food than early birds. More of their calories came from sugar. After 8:00 pm, the night owls ate more sugar and fat. Meanwhile ,early birds ate more protein during both the morning and the evening hours.

    "Night owls tend to be less healthy than early risers," notes Courtney Peterson who studies diet and meal timing. "They are more likely to get heart disease or cancer. The fact that night owls tend to eat more junk food probably plays a role," Peterson says. "Other factors(因素) also can ruin a night owl's health. Night owls generally sleep worse," says Peterson. "Poor sleep has been linked to unhealthy food choices. "

    Peterson and Maukonen say night owls tend to have poor eating habits. But that doesn't necessarily mean that being a night owl makes a person a poor eater. It could be the reverse- eating poorly could affect people's sleep habits.

"The new findings should serve as a wake-up call to night owls. For them, the new results should encourage paying attention to healthier lifestyle choices," says Maukonen. 28. How did Maukonen do research about people's risk of heart disease?