题干

红海中营群居生活的红鲷鱼有一种奇怪的现象,即在缺少雄性红鲷鱼的雌鱼群体中,总会有一条雌鱼变成雄鱼,且身体也变得比其他雌鱼健壮.为解释这一现象,有人做了如下两组实验(注:两组红鲷鱼生长状况、实验装置、条件及时间都相同).该实验说明(    )

第一组

   第二组

A:环境因素对生物的性状表现起到决定性作用

B:生物的性状表现由遗传物质决定

C:生物的性状表现是基因型与环境相互作用的结果

D:鲷鱼的性别决定与遗传物质无关

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答案(点此获取答案解析)

C

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    It took multiple weddings for Christine Law to realize what she needed to do. In the summer of 2014, her schedule was packed with friends, marriage celebrations—flowers --- filled occasions that got her thinking, “Where do all the flowers go after the party?” More often than not, they were thrown out. Law, then 27, was confident she could find a better use for them.

    By August, she had a plan: convince couples and companies hosting events to donate their flowers, which she would pick up and deliver within 48 hours to seniors across the city. She wanted to bring beauty into the lives of the elderly. She drew on her experience volunteering with non-profits in order to set up her own organization, which she called Floranthropie. Not having enough bouquets (花束) for all 150 people of a health center, Law asked the staff to provide a list of patients who needed cheering up most, “The first woman I approached thought it was a mistake, and that the flowers couldn't possibly be for her,” says Law. “I said they were a gift, and we talked for a half hour.”

    In addition to health centers, Floranthropie focuses on community groups devoted to the elderly. Theleme is a volunteer for Les Petits Fieres, an organization that aims to help the elderly who don't have a support system. The group receives a dozen or so bouquets from Floranthropie monthly, and then redistributes them. “Our motto is 'flowers before bread,” says Theleme. “We don't focus on primary care, but rather on nourishing (滋养) the spirit. Floranthropie helps that. It's amazing what a big difference a small bouquet can make.”

    In the beginning, most of Floranthropie's donations came through word of mouth. These days, Law receives messages from strangers via her organization's Facebook page and has connected with corporations and flower wholesalers. Law hopes to expand Floranthropie nationally, but at this point is happy to be able to oversee each delivery personally.