题目

A desert is a beautiful land of silence and space. The sun shines, the wind blows, and time and space seem endless. Nothing is soft. The sand and rocks are hard, and many of the plants even have hard needles instead of leaves. The size and location(分布) of the world’s deserts are always changing. Over millions of years, as climates change and mountains rise, new dry and wet areas develop. But within the last 100 yeas, deserts have been growing at a frightening speed. This is partly because of natural changes, but the greatest makers are humans. Humans can make deserts, but humans can als人类并指为显性遗传病（A控制），白化病是一种隐性遗传病（b控制），已知控制这两种疾病的等位基因都在常染色体上，而且是独立遗传．一家庭中，父亲并指，母亲正常，他们有一个患白化病但手指正常的孩子，如果他们再生一个孩子，则：（1）父亲的基因型是 ，母亲的基因型是 ，白化病但手指正常孩子的基因型是 ．（2）这个孩子表现正常的可能性是 ．（3）这个孩子只患白化病的可能性是 ，只患一种病的可能性是 ．（4）这个孩子同时患有两种病的可能性是 ．（5）这个孩子患病的可能性是 ．