Testing the Chemiosmosis Theory

Several kinds of evidence support the chemiosmotic theory of ATP synthesis in chloroplasts.

Link to discussion of the chemiosmosis in chloroplasts.

(a) When isolated chloroplasts are illuminated, the medium in which they are suspended becomes alkaline — as we would predict if protons were being removed from the medium and pumped into the thylakoids (where they reduce the pH to about 4.0 or so).

(b) The interior of thylakoids can be

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All living things must have an unceasing supply of energy and matter. The transformation of this energy and matter within the body is called metabolism.


Catabolism is destructive metabolism. Typically, in catabolism, larger organic molecules are broken down into smaller constituents. This usually occurs with the

The Interconversion of Fuels
Why we get fat from eating too many sweets!

The immediate source of energy for most cells is glucose.

How energy is extracted from glucose is described in
Glycolysis and in
Cellular Respiration.

But glucose is not the only fuel on which cells depend. Other

may in certain cells or at certain times be used as a source of ATP.

The complexity of the mechanism by which cells use glucose may make you fervently hope that a