1A 有叶绿体,能进行光合作用···························P
1 b 无叶绿体,不能进行光合作用··························2
2 a 无脊椎骨··································Q
2 b 有脊椎骨··································3
3 a 体温恒定,外被羽毛····························R
3 b 体温不恒定,体表裸露···························S
请选择上述五种生物中的四种填在后面四个空格:PQRS