Describe Structure of biological compounds?

Structure :  The most important chemical compounds in living systems are probably the organic compounds. The term "organic" in the past was used to refer to compounds that were thought to be formed only by living things. Today, the term "organic" is used to refer to chemical compounds containing carbon combined with hydrogen, and often oxygen. By convention, carbon dioxide, carbon monoxide, and carbonic acid are not considered to be "organic," even though they contain carbon.

Our form of life is often referred to as being "carbon-based." because carbon forms the basic structural framework (skeleton) of all living material. Long chains of carbon atoms, or backbones, form large molecules called macromolecules; which can be branched, or form single or compound rings. Macromolecules' ability to form a wide variety of shapes and sizes of molecules allows for an equally wide range of biological structures and functions. Various functional groups of atoms that determine the characteristics and chemical reactivity of the molecules are attached to the carbon backbones. Examples follow:

Living organisms are composed of 4 major types of organic compounds: carbohydrates, lipids, proteins, and nucleic acids.