How might deep-sea vents have been important in the origin of life?
The biotic factors were measured as follows:-
· A clipboard was placed within the quadrat, to form a uniform
that are thought to have led to the origin of life on Earth?
Dietary imbalances may also arise from the presence of disproportionate levelsof specific amino acids; including leucine/isoleucine antagonisms, and to a lesserextent arginine/lysine and cystine/methionine antagonisms. For example, blood mealis a rich source of valine, leucine and histidine, but is a very poor source ofmethionine and isoleucine. However, in view of the antagonistic effect of excessleucine on isoleucine, animals fed high dietary levels of blood meal suffer froman isoleucine deficiency caused by an excess of dietary leucine (Taylor, Cole andLewis, 1977). Although similar antagonisms have also been reported for cystine/methionine (use of hydrolysed feather meal; Ichhponani and Lodhi, 1976) and arginine/lysine (Harper, Benevenga and Wohlhueter, 1970) in terrestrial farm animals,they have not been found to occur in fish fed synthetic amino acid dietcombinations (Robinson, Wilson and Poe, 1981).
(The process of photosynthesis is explained
in more detail in my prediction)
Although light intensity seems to be the major factor affecting the
size of ivy leaves, there may have been some influence from other
abiotic factors that have also been measured and taken into account in
Abiotic synthesis of amino acids and nucleotides - could it happen?
Although numerous independent studies have recently been performed on theamino acid requirements of rainbow trout, significant differences in requirement(g amino acid/100g protein) exist within and between individual fish species(Table 2). For example, differences of the order of 65%, 72% and 114% wereobserved between independent laboratories for the lysine, arginine and methioninerequirement of fingerling/juvenile rainbow trout. Similarly, inter-speciesvariations ranged from 22% for valine to as high as 122% for tryptophan. Whilstone would have expected the quantitative EAA requirements of fish to decrease withage and decreasing protein synthesis (growth), one may well question whether ornot the observed variations in requirement are real or merely an artifact of themethod employed. In contrast to the variations in requirement observed for thesame fish species fed conventional amino acid test diets, there was no significantdifference in the EAA requirement of carp and trout on the basis of the carcassdeposition method of Ogino (1980a). However, the dietary requirements observedare within the range reported for fish fed amino acid test diets (Table 2).
JO - Origins of Life and Evolution of Biospheres
Although the NEAA are not dietary essential nutrients, they perform manyessential functions at the cellular or metabolic level. They are termed dietarynon-essential nutrients only because the body tissues can synthesize them ondemand. In fact it is often quoted that the NEAA are physiologically so essentialthat the body ensures an adequate supply by synthesis. From a feed formulationviewpoint, it is important to know that the NEAA's cystine and tyrosine can besynthesized within the body from the EAA's methionine and phenylalanine respectively,and consequently the dietary requirement for these EAA is dependent on theconcentration of the corresponding NEAA within the diet.
T2 - Origins of Life and Evolution of Biospheres
AB - The origin of guanine has been unknown, though there are some reports concerning its abiotic synthesis. We show here that guanine, as well as uracil and cytosine, are synthesized from a 90%N2-10%CO-H2O gas mixture via a complex organic product produced with the high-temperature and rapid quenching technique. This result implies that a large amount of complex organic matter including precursors of bioorganic compounds might have been produced on the primitive earth after cometary impacts.
JF - Origins of Life and Evolution of Biospheres
N2 - The origin of guanine has been unknown, though there are some reports concerning its abiotic synthesis. We show here that guanine, as well as uracil and cytosine, are synthesized from a 90%N2-10%CO-H2O gas mixture via a complex organic product produced with the high-temperature and rapid quenching technique. This result implies that a large amount of complex organic matter including precursors of bioorganic compounds might have been produced on the primitive earth after cometary impacts.