题干

在斜面培养基上接种时,其正确的操作顺序是(    )
①用左手大拇指、食指和无名指夹住在菌种试管和待接种的斜面试管,管口并齐,使斜面向上成水平状态
②右手拧松棉塞,但不取下
③在火焰边用右手无名指和小指夹两个棉塞,将它们取下,同时左腕转动,灼烧管口一周
④将接种环伸入管内,让环先接触培养基上未长菌的部位,使环冷却,然后轻轻挑取少量菌体
⑤右手拿接种环,在火焰上灼烧灭菌
⑥在火焰旁边迅速将沾有菌体的接种环伸到培养基的底部,由里向外轻轻画蛇形细线
⑦抽出接种环,再用火焰灼烧管口,并在火焰上方将棉塞塞上

A:①②③④⑤⑥⑦

B:①②⑤③④⑥⑦

C:①③②④⑤⑥⑦

D:②③①④⑤⑦⑥

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答案(点此获取答案解析)

B

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第二节

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

A garden that's just right for you

     Have you ever visited a garden that seemed just right for you, where the atmosphere of the garden appeared to total more than the sum(总和) of its parts? ____ . But it doesn’t happen by accident. It starts with looking inside yourself and understanding who you are with respect to the natural world and how you approach the gardening process.

____ 

     Some people maythink that a garden is no more than plants, flowers, patterns and masses of color. Others are concerned about using gardening methods that require less water and fewer fertilizers(肥料). ____ . However, there are a number of other reasons that might explain why you want to garden. One of them comes from our earliest years.

●Recall(回忆)your childhood memories

     Our model of what a garden should be often goes back to childhood. Grandma’s rose garden and Dad’s vegetable garden might be good or bad, but that’s not what’s important. ____--how being in those gardens made us feel. If you’d like to build a powerful bond with your garden, start by taking some time to recall the gardens of your youth. ____ then go outside and work out a plan to translate your childhood memories into your grown-up garden. Have fun.

A. Know why you garden

B. Find a good place for your own garden

C. It's our experience of the garden that matters

D. It's delightful to see so many beautiful flowers

E. Still others may simply enjoy being outdoors and close to plants

F. You can produce that kind of magical quality in your own garden, too

G. For each ofthose gardens, writer down the strongest memory you have