A.肾小管壁薄且周围缠绕着大量的毛细血管,有利于肾小管的重吸收作用 |
B.肺泡壁和包绕的毛细血管壁都是由一层上皮细胞构成,有利于肺泡与血液的气体交换 |
C.心房与心室之间,心室与动脉之间,四肢静脉内都有瓣膜,能防止血液倒流 |
D.抽血或输血时,针刺入静脉,并在针刺部位的下方(远心端)用胶皮管捆扎起来 |

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

