Any mechanism that protects a host from a parasite can be divided into one of two classes. A stable mechanism is one that does not break down to new strains of the parasite, which are unaffected by that mechanism. This is because the mechanism is beyond the capacity for micro-evolutionary change of the parasite. Stable mechanisms include horizontal resistance, natural pyrethins, nicotine sulphate, rotenones, mineral oil, Bordeaux mixture and other copper fungicides, dithiocarbamates. See also: Unstable protection mechanisms. Stamen
The male organ of a flower. When mature, the anthers release pollen for the fertilisation of a female ovule. Staple
The main item of a diet, hence 'staple crop' and 'staple food'. Staple crops can be divided in to major and minor staples. Starch
Starch is a polysaccharide used by many plants as a method of storing carbohydrates. It is a major constituent of the human diet, being obtained mainly from cereals and potatoes. Starvation
The word starvation is derived from the old English word meaning 'to die' but, in modern usage, it can also mean malnutrition. In either event, it is the result of a food deficiency.
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