单选题小麦的粒色由两对同源染色体上的两对基因R1和r1、R2和r2控制。R1和R2决定红色，r1和r2决定白色（说明R1和R2的遗传效应相同）。麦粒的颜色随R的数量增加而逐渐加深。将红粒（R1R1R2R2）与白粒（r1r1r2r2）杂交得F1，F1自交得F2，则F2的表现型有（）A4种B9种C5种D10种
单选题
小麦的粒色由两对同源染色体上的两对基因R1和r1、R2和r2控制。R1和R2决定红色，r1和r2决定白色（说明R1和R2的遗传效应相同）。麦粒的颜色随R的数量增加而逐渐加深。将红粒（R1R1R2R2）与白粒（r1r1r2r2）杂交得F1，F1自交得F2，则F2的表现型有（）
A
4种
B
9种
C
5种
D
10种
参考解析
解析：
暂无解析
相关考题：
有以下程序:includeusing namespace std;{public:TestClass(int r1,int r2){R1=r1;R2 有以下程序： #include＜iostream＞ using namespace std; { public: TestClass(int r1,int r2) { R1=r1; R2=r2; } void print(); void print() const; private; int R1,R2; }; void TestClass::print() { cout＜＜R1＜＜","＜＜R2＜＜end1; } void Testclass::print() const cout＜＜R1＜＜","＜＜R2＜＜end1; } int main() { TestClass a(5,4); const TestClass b(20,52); b.print(); return 0; } 执行后的输出结果是( )。A．5，4B．20，52C．0，0D．4，5
请参见图示。出于安全原因,需要禁止从站点2的R2路由器访问有关HQR1路由器的型号和IP地址的信息。为此,应采取哪项安全措施() A.在R1和R2之间安装IDS。B.在R1和R2之间安装IPS。C.在R1和R2之间安装防火墙。D.禁用与R2连接的R1接口的CDP。E.禁用R1和R2之间使用的任何路由协议并配置静态路由。
R1(AS1)－－－－－－R2(AS2)－－－－－R3(AS2)－－－－R4(AS2),R1在AS1,R2,R3,R4在AS2,R1和R2建EBGP,R2和R3IBGP,R3和R4IBGP,产生BGP路由从R1传给R2,问这条路有会不会在R4上出现,如果不会,怎么解决.
线路阻波器谐振回路对谐时，元件取值（）A、去谐电阻R1取2～3kΩ，R2越大越好B、去谐电阻R1取2～3kΩ，R2取100ΩC、R1和R2均取100ΩD、去谐电阻R1和测试电阻R2均取2kΩ
有阻值分别为R1和R2的两个负载，其中R1的电阻值是R2的N倍，把它们并联后接到电源上，则：（”x＾m”表示“x的m次方”）（）A、流过R1的电流是R2的N倍，R1消耗的功率是R2的N＾2倍B、流过R1的电流是R2的1/N，R1消耗的功率是R2的1/NC、流过R1的电流与R2的相同，R1消耗的功率是R2的1/N＾2D、流过R1的电流与R2的相同，R1消耗的功率是R2的N倍
Routers R1 and R2 are EIGRP neighbors. R1 has been configured with the eigrp stub connected command. Which of the following is true as a result？（）A、R1 can learn EIGRP routes from R2, but R2 cannot learn EIGRP routes from R1B、R1 can send IP packets to R2, but R2 cannot send IP packets to R1C、R2 no longer learns EIGRP routes from R1 for routes not connected to R1D、R1 no longer replies to R2's Query messagesE、R2n o longer sends to R1 Query messages
Two directly connected routers， R1 and R2， are both configured for OSPF graceful restart. R2 is able to switch packets in hardware， but R1 is not. If a network administrator logs on to R2 and performs a system reload， which will be the result？（）A、Traffic forwarded from R2 to or through R1 will continue to be forwarded based on the forwarding table state at the time of the reload.B、R2 will continue to forward traffic to R1， but R1 will drop the traffic because its neighbor adjacency with R2 has failed.C、R2 will continue forwarding traffic to and through R1， but R1 will drop this traffic because it is not capable of maintaining its forwarding state.D、All the traffic R2 is forwarding to or through R1 will be dropped while OSPF rebuilds its neighbor adjacency and forwarding tables.
设有进程P1和P2并发执行，都要享用资源R1，R2，使用资源情况如下： 进程P1：……申请R1……申请R2……释放R1…… 进程P2：……申请R2……申请R1……释放R2…… 判断是否会产生死锁，并解释其原因。
极性最大的是（）A、R1=β-D-洋地黄毒糖-β-D葡萄糖，R2=甲基B、R1=氢，R2=醛基C、R1=α-L鼠李糖，R2=醛基D、R1=α-L鼠李糖-β-D葡萄糖，R2=甲基E、R1=氢，R2=甲基
问答题设有进程P1和P2并发执行，都要享用资源R1，R2，使用资源情况如下： 进程P1：……申请R1……申请R2……释放R1…… 进程P2：……申请R2……申请R1……释放R2…… 判断是否会产生死锁，并解释其原因。
单选题以下ARM指令中不属于数据处理类指令的是（）AADC R1，R2，R3BLDR R1，[R2]CMOV R1，R2，LSL#4DORR R1，R2，R3