INDEX genetic factors

Some modern varieties of cereals such as wheat and rice achieve high yield potential through genetic factors for plant dwarfness that improve harvest index. A popular notion among plant breeders is that high-yielding... 

The success of core-top temperature calibrations indicates that physiological state, genetic variability, and depth and seasonality of production play secondary roles to the control on the sedimentary U37 index exerted by mean annual near-surface temperature. In most cases, these factors produce errors at the level of 1.5 °C or less in the global core-top calibration. To this observer s opinion, core-top data cannot be reconciled with the large variations in the U 7 index attributed to genetic or physiological factors by some culture studies. This does not indicate that the culture data are wrong in a technical sense, but that their results cannot always be extrapolated to the natural environment (Popp et al., 1998). 

If we multiply these operations (10 in total) by the factor 2 (which would index the polar/no polar properties of R-groups from the polypeptide chain) 20 occupancy possibilities for groups R are obtained, which is precisely the total number of amino acids present in the standard genetic code. 

Some 10-25% of the population have a genetic predisposition to hyperhomocysteinemia, which is a risk factor for atherosclerosis and coronary heart disease, as a result of polymorphisms in the gene for methylenetetrahydrofolate reductase. There is no evidence that supplements of vitamin Bg reduce fasting plasma homocysteine in these subjects, and like the tryptophan load test, the methionine load test may be an appropriate index of status in controlled depletion/repletion studies to determine vitamin Bg requirements, but not in population studies. 

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