Natural stress plant growth. When there is no water in the soil there are not very many nutrients to support plant growth. Drought also enhances the effects of wind. When drought occurs the soil becomes very dry and light. The wind picks up this dry dirt and carries it away. This action severely degrades the soil and creates a poor condition for growing plants. Plants have been exposed to the elements for thousands of years. During this time they have evolved in order to lessen the effects of abiotic stress. Signal transduction is the mechanism in plants that is responsible for the
Proofs involving the addition of natural numbers induction on "a", and so we have proved the base case "b" = 1. Now, suppose that for all natural numbers "a", we have "a" + "b" = "b" + "a". We must show that for all natural numbers "a", we have "a" + "S"("b") = "S"("b") + "a". We have This completes the induction on "b". Proofs involving the addition of natural numbers This article contains mathematical proofs for some properties of addition of the natural numbers: the additive identity, commutativity, and associativity. These proofs are used in the article Addition of natural numbers. This article will use the