题干

下列说法正确的是( )

①人群中的红绿色盲患者男性多于女性

②属于XY型性别决定类型的生物,XY(♂)个体为杂合子,XX (♀)个体为纯合子

③人类红绿色盲基因b在X染色体上,Y染色体上既无红绿色盲基因b,也无它的等位基因B

④女孩是红绿色盲基因携带者,则该红绿色盲基因是由父方遗传来的

⑤男性红绿色盲基因不传儿子,只传女儿

A:③④⑤

B:①②④

C:②④⑤

D:①③⑤

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D

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    In this day and age taking a photograph is easier than ever. There are cameras built into our phones, computers, iPods…The way we share photos has also changed. There was a time when you'd print your photos and put them into photo albums, but because of the advance in technology, all in technology, all this has changed.

    Not only do we have what seems like an endless amount of space to store photos on our devices, but we also have the Internet, especially social media. Social networks such as Facebook allow us to post our pictures and albums to share friends and family.

    While you could argue this easy ability to store, share and enjoy photos is fantastic, it could also be said that photographs have lost some of their meaning. I have over 1000 pictures on my smart phone and several thousand stored on my computer. I love posting my pictures on Facebook. Sometimes, however, I try to ask myself, will I really want to look back at this picture of a coffee or a selfie taken in a bathroom by myself? Probably not.

    Even though I'm guilty about sometimes taking meaningless and boring pictures like this, a couple of years ago, I decided to find a way to make my photographs more meaningful. How did I do this? Disposable (一次性)cameras! When I go on a trip, I always try to take a disposable camera. With only 27 pictures you can take, you really think about the photograph straight away. And finally, it's so much fun to get the pictures developed and look through them again.

    I admit that I couldn't live without social media or taking photographs with my smart phone, but I do think taking photographs has become less meaningful. That's why I'll continue using disposable cameras. It's a great way to make your photographs more meaningful.