The biochemistry of genetics / by J.B.S. Haldane.

  • Haldane, J. B. S. (John Burdon Sanderson), 1892-1964.
Date:
[1954]
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: The biochemistry of genetics / by J.B.S. Haldane. Source: Wellcome Collection.

    64/152 (page 60)
    62 THE BIOCHEMISTRY OF GENETICS alive on sugar; but they grow till their reserves are exhausted, so there is little wrong with their general metabolism. This at least suggests that chlorophyll synthesis is a very complex process. Attempts to elucidate the biochemical differences between different chlorophyll-less mutants have met with small success. One of the greatest gaps in our knowledge relates to the odours of flowers. These have a precise biochemical basis. They are very variable between species, and somewhat so within a species. They are of very great biological importance in attracting insects, and therefore of evolutionary importance. They are in some cases economically important, but as a field for biochemical and genetical research they have been greatly neglected. An equally interesting problem is that of self-sterility. In many plants there is a series of allelomorphs, S^, S^, S^, etc., such that the pollen tubes carrying Si cannot grow in the styles of plants carrying the same gene, such as or S^S^. For fertilization to occur, the pollen tube must carry a foreign gene, and presumably a foreign gene product, the exact opposite of the situation as regards tissue grafts in higher animals. It is tempting to suppose that we are concerned with colloidal gene products of the same kind of molecular size as the antigens.* If so, a single species can produce any of over fifty different ones. * Lewis (1952) has shown that in one species they are antigenic.