Presented by John Maddox
Protein formation by plants depends on processes that convert atmospheric nitrogen into essential chemicals.
Professor John Postgate at the Department of Biological Sciences. Suffolk University, talks about genetic research to improve the efficiency of this process, in order to increase world food supplies.
There has recently been an upsurge of interest in theories of relativity and gravitation.
Sir Hermann Bondi discusses the philosophical basis for this work.
Producers MICHAEL bright and MARGARET CHAMBERS