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According to the theory of punctuated equilibrium, at what rate does speciation occur? species change depending on the rate of natural selection. after periods of stasis, new species evolve relatively rapidly. species change slowly and eventually form new species. some species change quickly and others change slowly to balance the overall rate.

Which of the following is an example of a tissue on the digestive system a.the stomach b.smooth muscle that lines the stomach c.nerve cells in the stomach d. enzyme molecules in the stomach

The response is the basis for vaccination. primary secondary tertiary none of the above