Prometheus, or, biology and the advancement of man / by H.S. Jennings.

  • Herbert Spencer Jennings
Date:
[1925]
Catalogue details

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

Credit: Prometheus, or, biology and the advancement of man / by H.S. Jennings. Source: Wellcome Collection.

    40/112 (page 36)
    PROMETHEUS diverse ; the different structures of the body are being made. This is repeated in each cell generation, the chromosomes by interaction with the cytoplasm changing the substance of the cells, until finally nerve, muscle, bone, gland and other tissues result. But in aU this interaction of the chromosomes to produce new cytoplas¬ mic materials, the chromosomal materials—the genes—^are not them¬ selves used up. Always a reserve portion of each chromosomal substance is saved ; so that none of them are lost, and their number does not decrease. And at each cell division every reserve packet is divided, half of it going to each of the two cells, where it grows to full size. So every cell of the body continues to contain the entire set of the parental chemicals, just as the egg [38]