|MadSci Network: Cell Biology|
Dear Matt, It really depends on where the cell is located,ie in which tissue and organ. Generally, metabolites like simple sugars (Glucose, fructose, galactose), essential and non-essential amino acids and fatty acids are needed by the cell for metabolism & synthesis of biological compounds. Lipophilic compounds diffuse through the membrane. Large, polar uncharged compounds enter the cell membrane using tranporter or channel. Ions such as calcium, sodium and phosphate enter the cell by specific energy-dependent transporters. Water and Oxygen are much needed materials for cell survival. Their entry is through simple diffusion. Molecules like urea and carbon dioxide leave the cell as waste products. It really depends on what cell you are refering to know what are the waste products. Reference: Biochemistry by Donald Voet and J.Voet
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