题干

孟德尔用豌豆进行杂交实验,成功地揭示了遗传的两个基本规律,为遗传学的研究做出了杰出的贡献,被世人公认为“遗传学之父”.下列有关孟德尔一对相对性状杂交实验的说法中,不正确的是(  )

A:豌豆是自花受粉,实验过程免去了人工授粉的麻烦

B:解释实验现象时,提出的“假说”是:F1产生配子时,成对的遗传因子分离

C:解释性状分离现象的“演绎”过程是:若F1产生配子时,成对的遗传因子分离,则测交后代出现两种表现型,且比例接近1:1

D:检测假设阶段完成的实验是:让子一代与隐性纯合体杂交

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A

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Why I Love Cycling

    One of the first things I did when I moved to a new city was hire a bike. Why?____ You travel much faster than on foot and you notice so much more of your surroundings than when in a bus or a car. It's more appealing to wander down small streets if they seem interesting, as you can quickly get back to the main road.

    Besides, I soon discovered plenty more benefits to cycling.

    A bike means that fewer places, especially in a small city like the one where I live now, feel far away. For example, cycling to work takes me half the time that it would to walk.____

    Of course, there are obvious health benefits of cycling—a bit of extra movement as part of your daily routine can help you keep fit and healthy. Cycling on my way to work also makes me feel more energetic in the mornings.

    ____ While cars pollute the environment, bikes are carbon-neutral. Furthermore, thanks to being petrol-free, bikes are cheaper to run, buy and fix than cars. Even if you don 'town a car, a bike can pay for itself when compared to the price of bus tickets.

    ____ Always wear a helmet, pay attention to other traffic and don't forget your lights at night. Make sure you know the road rules, especially in a new place. Some cities are more cycle-friendly than others.____ Luckily, where I live now is pretty easy to ride a bike around, thanks to having lots of cycle lanes and not too many hills!

A. However, be careful when cycling.

B. I have to learn to ride safely on the right of the road.

C. Importantly, cycling also helps to reduce your carbon footprint.

D. And sometimes city roads are difficult or unpleasant for cyclists.

E. Riding a bike also means you're not restricted by bus timetables.

F. Seeing a city by bike is ideal for settling in and learning your way around.

G. Cycling to work excellently fits for someone who wants to save their pocket money.