1) Describe the relationship between carbon and human activities represented in the model. 2) Explain how the human activities highlighted in your model have affected global climate.

3) Provide examples from your model of conservation of matter through Earth’s spheres.

4)Identify the limitations of your carbon model in accounting for all of Earth’s carbon.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

the tricuspid valve is present between right atrium and right ventricle