A.毛细血管管壁薄、管腔细、血流速度慢,适于进行物质交换 |
B.肾小球和肾小囊内壁都只由一层上皮细胞构成,适于重吸收作用 |
C.肺泡数目多壁薄,外面有毛细血管和弹性纤维,适于进行气体交换 |
D.小肠壁的内表面有环形皱襞和小肠绒毛,使小肠的吸收面积大大增加 |
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