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The Nutrient Requirements of Cells

Introduction

In order to keep running, all living things need an unceasing supply of energy and materials. One useful way to discover the nutritional needs of cells is to attempt to culture them in the laboratory. We shall examine the ingredients needed in the medium for culturing

Minimal Medium for E. coli
(grams/

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The Energetics of Transport Across Membranes

The movement of any molecule or ion down — or up — a concentration gradient involves a change in free energy, ΔG ("Delta G")

  • down releases energy so ΔG is negative
  • up consumes energy so ΔG is positive
Link to a discussion of free energy changes.

The amount

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The Extracellular Matrix (ECM)

While it is true that all living things are made of cells, that is only part of the story. Most of the cells in multicellular organisms are surrounded by a complex mixture of nonliving material that