5^6 School Science and Mathematics

influence is substantial. Let us go beyond scientific literacy as a goal�let us contribute to the intellectual and moral growth of betterhuman beings.

BIBLIOGRAPHY[1] AXJSUBEL, DAVID P., "Some Psychological and Educational Limitations of

Learning by Discovery." The Arithmetic Teacher, Vol. II, 1964, pp. 290-302.[2] CRONBACH, LEE J., "The Logic of Experiments on Discovery" in Learning by

Discovery�A Critical Appraisal, Chicago: Rand McNally and Co., 1966.[3] WITTROCK, M. C., "The Learning by Discovery Hypothesis" in Learning by

Discovery�A Critical Appraisal, Chicago: Rand McNally and Co., 1966.[4] CAWS, PETER, The Philosophy of Science, New York: D. Van Nostrand Co.,

Inc., 1965, p. 13.[5] MARGENAU, HENRY, Open Vistas, New Haven: Yale University Press, 1961,

pp. 4-38

ENERGY RELEASE IN CELLSThe operation of a new energy form in biological systems has been discovered

after a 20 year quest at the University of Wisconsin’s Institute for EnzymeResearch. Drs. David E. Green and John H. Young revealed the mechanism bywhich energy is transformed in the cell’s powerplants�the mitochondria.

"This is probably the key to energy transformation in all the cell’s membranesystems, be it stomach secretion or nerve impulse transmission," said Green.The problem of how energy is transformed in living membrane systems

stumped researchers until the introduction of the electron microscope in the early^60s."With the high magnification," Green explained, "we saw the toadstool-like

machines which fit together like bricks in a wall to make up the mitochondrion^smembrane."When better methods for rapidly fixing mitochondria for study were devel-

oped, we could actually see these mitochondrial machines at work."The researchers first found that these tiny machines undergo rhythmic pulsa-

tions, much like the opening and closing of an umbrella.Subsequently, they observed that these structural changes always accom-

panied energy transformation."These pulsations," noted Young, also with Wisconsin^ Theoretical Chemis-

try Institute, "led to our recent discovery that protein systems can becomeexcited by oxidation just as simple molecules can be excited by light."The energy stored in these excited machines is then used to perform work. In

the case of the mitochondria, work constitutes either active transport or themanufacturing of ATP, an energy storing molecule. Green and Young describedhow active transport�the movement of chemicals through a living membrane�can be explained by their model.The Wisconsin team, composed of Green, Young, George Blondin, Martin Lee,

Gary Vanderkooi, and David Allmann, are now directing their attention to thelast key piece of the puzzle�how the mitochondrial machine in the excited statecan make ATP."We haven^t yet devised a model to describe how this is done," Green said,

"but we feel sure the pattern already established for active transport will pointthe way to the solution."