14. what two things limit the size of cells?
15. why is surface area and volume important for cell sizes?
16. what limits cell division?

14. Surface Area , and Volume Area limits the size of cells.

15 .A cell is a metabolic compartment where a multitude of chemical reactions occur. The number of reactions increase as the volume of metabolic volume within a cell increases. (The larger the volume the larger the number of reactions)  
All raw materials necessary for metabolism can enter the cell only through its cell membrane.  
The greater the surface area the larger the amount of raw materials that can enter at only one time.  
Each unit of volume requires a specific amount of surface area to supply its metabolism with raw materials. The amount of surface area available to each unit of volume varies with the size of a cell.  
As a cell grows its SA/V decreases.  
At some point in its growth its SA/V becomes so small that its surface area is too small to supply its raw materials to its volume. At this point the cell cannot get larger.

16. Cells only divide when they receive specific signals from proteins called mitogens,the presence of mitogens can limit cell division. Mitogens are needed for cell division in healthy cells and are released depending on what cells the body needs.

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