A.与胸腺嘧啶脱氧核苷酸相比,尿苷中特有的成分是尿嘧啶 |
B.干细胞衰老后仍具有细胞的全能性,细胞核内遗传物质改变 |
C.干细胞衰老后细胞核体积缩小,端粒DNA序列逐渐缩短 |
D.尿苷可能通过阻止自由基破坏干细胞内的生物分子来延缓干细胞衰老 |

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

