What are the organs that make up the circulatory system

Explain the importance of producers, primary consumers, secondary consumers and decomposers in an ecosystem.

The phylogenetic tree illustrates the relationship between humans and our closest living relatives. the tree was based on biochemical comparisons, including dna and amino acid sequences. according to the biomolecular data, we could infer that

How does science influence the decisions made about social, economic, and political issues?