How do cyclins enable cells to pass cell cycle checkpoints? put the following steps in the correct chronological order: 1) cyclin/cdk complex is activated by cak 2) cyclin/cdk complex phosphorylates target proteins 3) cyclin accumulates 4) cyclin becomes ubiquitylated 5) cyclin complexes with cdk

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.