题干

下面是我国北方某草原生态系统中部分食物网简图,据图判断下列说法正确的是(  )

①图中所有生物构成了生物群落②图中食物网中共有4条食物链③蛇处于不同营养级④青蛙和蜘蛛的关系不只是捕食.

A:①③④

B:①③

C:①④

D:②③④

上一题 下一题 0.0难度 选择题 更新时间:2019-08-14 03:08:54

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D

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    Growing up in Wyoming,everyday life was an adventure—I spent my time camping,and exploring mountains. When I was little,my mom became the state's first female U.S. Marshall.I'll never forget how the local newspaper praised her for her success in a field that's traditionally run by men.Under her influence,I made up my mind to achieve something great.Now,I've become famous for sailing,a sport often considered "a man's world".

    Sailing is considered a hard-to-break-into sport.And,generally,there are only two ways to get into it—either through a strict sailing education that leads to experience or by growing up on the water and racing in the Olympics. Most of my teammates became professional sailors in one of these two ways but I skipped both.

    In the summer of 2008,I went to St.Croix through a college internship(实习)program focusing on educating locals about HIV and AIDs.There,I discovered my love for sailing.Then,SCA,a global hygiene(卫生保健)company, made the decision to support an all-female team,and when they began accepting applications,I knew it was the chance of a lifetime.I made it my task to become a part of the team.Even when it seemed like there were no positions left,I never gave up.

    After a stressful,two-year application process,I finally got the call.I moved to Lanzarote in the Canary Islands and began training with the team immediately.The process was physically,mentally and emotionally exhausting,but I finally achieved my goal.I sailed in the "Everest of sailing" with only six years' experience.Later,there was an all-female team competing,and I was lucky enough to be a part of it.

    As women,we need to approach our dreams as if we deserve to achieve them as much as men,because we do. There are plenty of professions,including sailing,in which women are absent or have a minor presence—but that's not because they shouldn't be there.We need to push the boundaries and focus on obtaining our goals and passions,no matter how unobtainable and challenging they may seem.