8. Protein synthesis
9. d option
11. Golgi bodies
14. Robert brown
15. Active transport
16. Chloroplast, photosynthesis
18. Plant cell
21. plant cell
Sodium ion concentrations in a resting cell are an example of Potential Energy, and sodium ion movement in a stimulated cell is an example of Kinetic Energy.
In resting cell there is a voltage difference between extracellular fluid and intracellular fluid(E.g -70mV for nerve cell), So this voltage is required for maintaining the resting state(no action potential is not generated in this state). In this condition cell stored energy as a potential difference. This potential energy is used for the stored or inactive state of the particular cell.
But, whenever a cell is stimulated that potential energy converted to kinetic energy(by opening sodium channel) and for this reason energy propagated through the cell to target region by action potential. So the inward sodium ion movement in a stimulated cell is an example of kinetic energy. This kinetic energy is used for the action of that particular cell.
Wrong Option: First option is incorrect because, in resting state there is no flow of sodium so this state can't be an example of the energy of motion, and in excited cell there is a flow of sodium ion so this state also can't be a example of stored energy.
Last option is also incorrect because in excited state of a cell there is no energy stored in chemical bonds, in this state stored energy transfer into action, so last option is also incorrect.
The cell membrane controls the movement of substances in and out of cells and organelles. In this way, it is selectively permeable to ions and organic molecules.