题干

以下有关变异的叙述,正确的是(  )

A:用普通二倍体西瓜培育出四倍体西瓜,再用普通二倍体西瓜给四倍体西瓜授粉,则四倍体植株上会结出三倍体无子西瓜

B:基因重组所产生的新基因型不一定会表达为新的表现型

C:基因重组导致杂合子Aa自交后代出现性状分离,产生新的基因

D:花药离体培养过程中,基因重组、基因突变和染色体变异均有可能发生

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B

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    Money Matters

    Parents should help their children understand money.____So you may start talking about money when your child shows an interest in buying things, candy or toys, for example.

    1)The basic function of money

    Explaining the basic function of money by showing how people trade money for goods or services is important to show your child how money is traded for the thing he wants to have.

    If he wants to have a toy, give him the money and let him hand the money to the cashier.____When your child grows a bit older and understands the basic function of money, you can start explaining more complex ways of using money.

    2)Money lessons

    Approach money lessons with openness and honesty.____ If you must say no to a child’s request to spend money, explain, “You have enough toy trucks for now". Or, if the request is for many different things, say, “You have to make a choice between this toy and that toy.”

    3)____

Begin at the grocery store. Pick out similar brands of a product-a name brand butter and a generic(无商标产品),for example. You can show your child how to make choices between different brands of a product so that you can save money.____ If he chooses the cheaper brand, allow him to make another purchase with the money saved. Later, you may explain how the more expensive choice leaves less money for other purchases.

A. The value of money.

B. Wise decision.

C. The best time to teach a child anything about money is when he shows an interest.

D. Ask yourself what things that cost money are most important to you.

E. Tell your child why he can—or cannot—have certain things.

F. Talk about how the money bought the thing after you leave the toy store.

G. Permit the child to choose between them,