Which of the following are considered chemical building blocks of all body structures?

Molecules are indeed the chemical building blocks of all body structures. They are composed of two or more atoms bonded together and form the basis for all biological processes. Molecules can include a variety of substances such as proteins, carbohydrates, lipids, and nucleic acids, which play vital roles in the structure and function of cells and tissues in the body.

For example, proteins, which are made of amino acid molecules, are essential for the structure of cells and tissues, serving as enzymes, hormones, and structural components. Similarly, nucleic acids like DNA and RNA are crucial for storing and transmitting genetic information. The intricate arrangement of molecules is what gives rise to the complexity of various body structures.

Atoms serve as the foundational units of molecules but by themselves do not constitute the larger structures necessary for biological organization. Cells are the basic units of life and are composed of numerous molecules, while tissues are made up of multiple cells that perform specific functions. Thus, while atoms, cells, and tissues are all essential to the human body, it is molecules that serve as the direct chemical building blocks.