Hello there.
<span>Regulation of the cell cycle is dependent upon cyclins and cyclin-dependent kinases. The key(s) that allows a cell to progress beyond the restriction point is (are)
</span><span>c. cyclin A and Cdk2.
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B - energy flow from one tropic level to the next
A mother's diet before conception can permanently affect how her child's genes function, according to a study published in Nature Communications. A 2003 study found that a female mouse's diet can change her offspring's coat color by permanently modifying DNA methylation.
Sharks, like all vertebrates, have bilateral symmetry. This
means they have symmetry across one plane (known as the sagittal
plane, and directly down the centre of their body), which means one