Light gathering structures

Cyanobacteria are believed to be the ancestors of plant cells. In the ancient seas, heterotrophic cells probably fed on cyanobacteria, engulfing them whole. Instead of digesting these prey, the heterotrophic cells were able to maintain them in membrane-bound sacs. The cyanobacteria continued to photosynthesize, making their own food and providing food for their new hosts. Over time, these two individual cells became an inseparable team, dependent on each other for support. The cyanobacteria acted as the light-gathering structure for the two, and the duo evolved into primitive plant cells. 

See also Mitochondrial Structure and Function (from Chapter 15), Basic Processes of Photosynthesis, Light Gathering Structures, Chloroplast Anatomy, Thylakoid Lumen, Chlorophyll, Chloroplasts... 

See also Light Gathering Structures, Energy of Light, The Chloroplast, Photosystem II, Photosystem I, Thylakoid Membranes, Porphyrin and Heme Metabolism (from Chapter 21)... 

See also Light Absorbing Pigments, Light Gathering Structures... 

One of the important properties of porphyrins is that they complex with divalent metals, the pyrrole nitrogens being ideally spaced to allow this. Of vital importance to life processes are the porphyrin derivatives chlorophyll and haem. Chlorophyll (actually a mixture of structurally similar porphyrins chlorophyll a is shown) contains magnesium, and is, of course, the light-gathering pigment in plants that permits photosynthesis. 

Changes in such physical factors as light, temperature (particularly maximums and minimums), relative humidity, and wind speed in forest communities subject to structural alteration by mortality of susceptible species could change the suitability of some sites for growth, reproduction, and re-establishment of survivor species. We can only speculate on some of the possible secondary effects until more data are gathered. ... 

A population of RNA-like polymers adsorbed at a ZnS template could gather light and therefore enhance the yield of the photocatalysis. Since the hydrothermal ZnS structures are highly porous [179-181], the pores/ compartments that contained efficient replicators and, hence, an increasing number of UV-absorbing zymes could produce more metabolites, which, in turn, could be used to build new replicators, resulting in a kind of positive feedback. 

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