|MadSci Network: Cell Biology|
Cells get their food for matabolic and catabolic activities from the outside world. Transportation of food for these activities either by blood circulation or through other means as in case of plants is an indespensable part to keep the cells alive. A cell is a dynamic system. The non living materials enter in and out of the cell through many physical and bio-chemical processes. A cell can be considered as a complex bio-chemical engine. Cells do synthesize bio-molecules required for division. These include proteins, duplication of DNA, etc. The basic raw materials required for these processes are required to be supplied from outside. The supply process itself is quite complex in multi-cellular organisms. Most of these things are controlled by cell membrane.
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