32.(1)R和r(回答完整才得分)(1分)B系和R系(1分)(2)繁殖A系的方案:以A系作母本与B系杂交,从A系植株上收获的F1即为A系(2分)繁殖B系的方案:B系自交即可实现繁殖(2分)繁殖R系的方案:R系自交即可实现繁殖(2分)(3A系花粉不育,只能作为母本杂交,从A系植株上收获的F1的核基因型均为Rr。若用B系与R系杂交,由于二者均能自交,F1的核基因型中除Rr外,B系上还有rr,R系上还有RR,因此需要对母本品系进行人工去雄处理,花小且工作量大,难以大量获得(4分)解析:(Ⅰ)核基因才会遵循基因分离定律,质基因不会遵循此定律;A系为雄性不育系,不能产生可育花粉。(2)因A系为雄性不育系,因此繁殖A系时要以A系作母本与B系杂交,A系提供质基因S、核基因r,B系提供核基因r;繁殖B系只需要B系自交即可;繁殖R系只需要R系自交即可。(3)A系花粉不育,只能作为母本杂交,从A系植株上收获的F1的核基因型均为Rr。若用B系与R系杂交,由于二者均能自交,F1的核基因型中除Rr外,B系上还有r,R系上还有RR,因此需要对母本品系进行人工去雄处理,花小且工作量大,难以大量获得

书面表达One possible version:NOTICEA sports meeting will be held in the playground of our school from next Thursday to FridayAs you know, the pressure of study is very heavy now, especially for those senior 3. So the purpose of the sports meeting is to letevery student get relaxed, as a result of which we students can live happily and heal thilyEveryone is welcome to take part in it. Those who perform excellently at the sports meeting will get prizes. But don' t take theresults so serously because taking part is more important than the result. Good luck to everyone!

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