Answer:
D. Cyclin
Explanation:
Cyclins drive the events of the cell cycle by partnering with a family of enzymes called the cyclin-dependent kinases (Cdks). A lone Cdk is inactive, but the binding of a cyclin activates it, making it a functional enzyme and allowing it to modify target proteins.
The renewable energy source is Hydroelectricity.
The cuticle decreases water loss and stomata assist gas exchange. The plants from wet habitats must have a comparatively large number of stomata and thin cuticle. The plants existing in dry habitats must have comparatively few stomata and thick cuticle.
