Comment on “Fundamental molecules of life are pigments which arose and co-evolved as a response to the thermodynamic imperative of dissipating the prevailing solar spectrum” by K. Michaelian and A. Simeonov (2015).

This is a comment on Michaelian and Simeonov (2015). Michaelian and Simeonov formulate the leading thought in their article: “The driving force behind the origin and evolution of life has been the thermodynamic imperative of increasing the entropy production of the biosphere through increasing the global solar photon dissipation rate”. I shall in the following try to provide some information that might help to clarify whether this is correct

The evolution of photosynthesis and chloroplasts

This review focuses on what has been learned about the evolution of photosynthesis in the past five years, and omits evolution of CO2 assimilation. Oxygenic photosynthesis (using both photosystems I and II) has evolved from anoxygenic photosynthesis. The latter occurs in different variants, using either a type 1 photosystem resembling photosystem I, or a type 2 photosystem resembling photosystem II. Opinions differ as to how two types of photosystem came to be combined in the same organism, whether by gene transfer between bacteria, by fusion of bacteria, or as a result of gene duplication and evolution within one kind of bacterium. There are also different opinions about when oxygenic photosynthesis arose, in conjunction with the Great Oxygenation Event, 2.3 billion years before the present, or more than a billion years before that. Cyanobacteria were the first organisms to carry out oxygenic photosynthesis. Some of them gave rise to chloroplasts, while others continued to evolve as independent organisms, and the review outlines both lines of evolution. At the end we consider the evolution of photosynthesis in relation to the evolution of our planet

Sinnesorganet i växtrotens spets

A popular overview of recent research into the various sensory organs of the plant root is given

Ginkgo – det kinesiska tempelträdet

Abstract is not availabl

Fotosyntesprocessens evolution

Fotosyntesen är växternas fantastiska och för oss livgivande metod att med hjälp av energin i solljuset omvandla luftens koldioxid till växtbiomassa och syre. Men många lägre organismer har en fotosyntes som inte producerar nŒgot syre, medan åter andra organismer kan binda koldioxid med hjälp av någon annan energikälla än solljuset. Lars Olof Björn och Jan Bergström reder ut begreppen

Evolution of the Z-Scheme of Electron Transport in Oxygenic Photosynthesis

We start with the discussion of the photosynthetic unit, based on the experiments of Emerson and Arnold (1932a, 1932b), continue with the first two-quantum proposal by Rabinowitch (1945, 1956), Emerson's Red drop (1943) and Emerson Enhancement Effect (1957) and various action spectra made for understanding the roles of the photosynthetic pigments. The experimental work of Kok (1959) and the theoretical model by Hill and Bendall (1960) were followed soon thereafter by the seminal papers of Duysens et al. (1961) and Duysens and Amesz (1962), in which the two photosystems were shown to be connected, in series, by cytochrome, which can be photooxidized by photo system I and photoreduced by photosystem II. Further, Witt et al. (1961) and others, cited in this paper, made refinement of the Z-scheme

Communication Enabling the Implementation of Innovation

Abstract. This paper describes the proposed research approach of a research project called, Communication Enabling the Implementation of Innovation. The point of departure for the project is a view on innovation described as hard work rather than mere creativity or inventions. This leads to the conclusion that innovation processes can be supported and enhanced through planned activities. The paper promotes a perspective linking innovation to the well established concept of a learning organization. The aim for the research project is threefold; 1) to generate a method for the development on an index measuring "innovation maturity" of organizations. 2) to generate specific measures of innovation processes and 3) to develop a feedback system enhancing the innovative organizations towards a learning organization