The answer is <span>The respiratory system supplies the oxygen that the cardiovascular system transports to the different cells for the production of energy.
When air enters the lungs (part of the respiratory system), it passes all way to the alveoli, the smallest functional units of the lung. There, oxygen from the air enters the capillaries, the smallest blood vessels, next to the alveoli. Once in the blood stream, the cardiovascular system transports oxygen to different cells where it is used for the energy production.</span>
The answer is Succession. It is the gradual sequential regrowth of a community of species after a forest fire. Particularly, Secondary Succession, which is the sequential replacement of species that follows disruption of an existing community (natural disaster or forest fire)
The nucleus resembles the brains function.
Answer:

Plasmodesmata play roles in both cellular communication and in molecule translocation. Plant cells must work together as part of a multicellular organism (the plant); in other words, the individual cells must work to benefit the common good. Therefore, communication between cells is crucial for plant survival.