题干

豚鼠的黑色和白色是一对相对性状。两只黑色的豚鼠交配后,共产下4只豚鼠,其中2只黑色豚鼠,2只白色豚鼠。对这种现象分析正确的是(    )

A:豚鼠的白色性状是由显性基因控制的

B:这种现象称之为性状分离

C:后代比例不是3:1,所以这对性状的遗传不符合孟德尔分离定律

D:如果再生一只豚鼠,是白色雌鼠的概率是14

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答案(点此获取答案解析)

B

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    Singapore is building an airport where indoor trees, waterfalls and a 'rain vortex' sit alongside check-in queues, waiting rooms and baggage carousels(传送带).

    Where once sat a car park, there will soon be thousands of trees and plants across 22,000 square metres of landscaped indoor parklands. This will be joined by a 40m-high indoor waterfall, expected to be the world's tallest. These are the plans for the new 3.5 hectare 'Jewel' development at Singapore's Changi Airport, scheduled to open in 2018; a five-story, 134,000 square metre complex, mixing natural outdoor plants with modern airport facilities.

    “The aim behind the introduction of such lush(茂盛的) landscaping is purely to provide all visitors with a memorable experience, one where they are surrounded by nature and greenery,”says Philip Yim, Chief Executive Officer of Jewel Changi Airport Development.

    Promised sustainability(持续性) measures include “extensive usage of photovoltaic panels(光电板)”to produce renewable energy, as well as encouraging the use of natural lighting and a “high efficiency” air-conditioning system.

    The indoor waterfall, named the “Rain Vortex”, will make use of special lighting effects to change at night into what is promised to be a dramatic light and sound show. “The Rain Vortex is one example of how sustainable design plays an important role in the planning of the attraction,” says Yim. 'In the event of a rain storm, the power of the rain water will flow naturally through the oculus. The excess rain water collected will be used for irrigation of the landscaping at Jewel.'

    Yim quotes the popular reputation Singapore enjoys as “the garden city”, where greenery is recognised as an essential part of the urban landscape, an attractive image which clearly inspires Jewel's design.

    However, it remains to be seen whether, beyond the aesthetic (审美的) appeal, Jewel can add genuine environmental things to something as un-environmental as an international airport.