A:♀rr×♂rr
B:♀Rr×♂rr
C:♀rr×♂RR
D:♀Rr×♂rRr
下图是原尿中某种物质在流经肾小管形成尿液的过程中其浓度变化示意图。据此推断该物质是( )
细胞分化是生物界普遍存在的一种生命现象,下列叙述中正确的是( )
—Yes, it's famous ________ its rice and seafood.
The bus driver stopped the bus ____ ____ twice.