hydrogen
2.4 | Inorganic Compounds Essential to Human Functioning By the end of this section, you will be able to: Compare and contrast inorganic and organic compounds Identify the properties of water that make it essential to life Explain the role of salts in body functioning Distinguish between acids and bases, and explain their role in pH Discuss the role of buffers in helping the body maintain pH homeostasis The concepts you have learned so far in this chapter govern all forms of matter, and would work as a foundation for geology as well as biology. This section of the chapter narrows the focus to the chemistry of human life; that is, the compounds important for the bodys structure and function. In general, these compounds are either inorganic or organic. An inorganic compound is a substance that does not contain both carbon and hydrogen. A great many inorganic compounds do contain hydrogen atoms, such as water H2O and the hydrochloric acid HCl produced by your stomach. In contrast, only a handful of inorganic compounds contain carbon atoms. Carbon dioxide CO2 is one of the few examples. An organic compound, then, is a substance that contains both carbon and hydrogen. Organic compounds are synthesized via covalent bonds within living organisms, including the human body. Recall that carbon and hydrogen are the second and third most abundant elements in your body. You will soon discover how these two elements combine in the foods you eat, in the compounds that make up your body structure, and in the chemicals that fuel your functioning. The following section examines the three groups of inorganic compounds essential to life: water, salts, acids, and bases. Organic compounds are covered later in the chapter.