The macromolecule that provides building blocks for tissue and helps regulate chemical reactions is protein. Here's why:

* Building Blocks for Tissue: Proteins are the primary structural components of cells and tissues. They form the framework of organs, muscles, skin, hair, and more.

* Regulation of Chemical Reactions: Proteins act as enzymes, which are biological catalysts that speed up chemical reactions in the body. They play crucial roles in metabolism, digestion, and many other essential processes.

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