Which substances are considered organic biological substances?

The correct answer identifies carbohydrates and fats as organic biological substances because they are compounds that contain carbon and are integral to biological functions.

Carbohydrates serve as a primary energy source for living organisms and are vital in cellular structure and metabolism. They consist of sugar molecules, which can be simple or complex, and are crucial for energy storage and providing structural components in cells.

Fats, or lipids, are another essential category of organic biological substances. They perform several critical roles, such as energy storage, forming cell membranes, and serving as signaling molecules. Fats are also important for the absorption of fat-soluble vitamins and for maintaining healthy skin and hair.

In contrast, substances like water and salt are inorganic and do not fit the definition of organic biological substances since they do not contain carbon in a structural context. Plastics and silicones are synthetic materials primarily created from petrochemicals and do not naturally occur in biological systems. Lastly, minerals and metals are also inorganic elements crucial for various physiological functions but are not classified as organic biological substances.