A.蝗虫体表坚韧的外骨骼有保护和防止水分蒸发的作用 |
B.青蛙的皮肤裸露,皮肤里密布毛细血管,能进行气体交换 |
C.家鸽前肢变成翼,翼上的肌肉发达,牵动两翼在空中飞行 |
D.人的肺泡壁和毛细血管壁都由一层上皮细胞构成,适于进行物质交换 |

同类型试题

y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2


y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2

