Answer:
Cyclin is a family of proteins that controls the progression of a cell through the cell cycle by activating cyclin-dependent kinase (CDK) enzymes or group of enzymes required for synthesis of cell cycle.
Cells are the most simple level of organization, as tissues contain cells, organs contain tissues and systems contain organs, so R would be your answer.
Answer:
Explanation:
Xylem transports and stores water and water-soluble nutrients in vascular plants.
Phloem is responsible for transporting sugars, proteins, and other organic molecules in plants.
Vascular plants are able to grow higher than other plants due to the rigidity of xylem cells, which support the plant.
One of the factor is the Sun's elevation where the UV reaches us at a much lower frequency when the sun is more distant. Next is our ozone, with our ozone depleting as time goes by, the amount of solar energy it can diffuse is much lesser thus the heat is much more than the previous decades.
