Final answer:
The building blocks for the synthesis of organic compounds in humans emanate from all four major classes: carbohydrates, lipids, proteins, and nucleic acids. Nucleotides are the specific building blocks of nucleic acids, consisting of phosphate groups, a pentose sugar, and a nitrogenous base.
Step-by-step explanation:
In humans, most of the building blocks necessary for the synthesis of organic compounds come from carbohydrates, lipids, proteins, and nucleic acids. These are the four major classes of organic compounds that are critical to human structure and function. Each plays a vital role, with carbohydrates serving as a primary energy source, lipids functioning in long-term energy storage and as components of cellular membranes, proteins serving crucial roles in structural support and catalysis of biochemical reactions, and nucleic acids (DNA and RNA) storing and transmitting genetic information.
The building blocks of these organic compounds include monosaccharides (simple sugars) for carbohydrates, fatty acids for lipids, amino acids for proteins, and nucleotides for nucleic acids. When looking at nucleic acids, the basic building blocks are nucleotides, each made up of three subunits: one or more phosphate groups, a pentose sugar (deoxyribose or ribose), and a nitrogen-containing base (adenine, cytosine, guanine, thymine, or uracil).
So, the answer to the question about the building blocks of nucleic acids is (d) nucleotides, and as for the initial question, the basic components necessary for the synthesis of organic compounds generally come from all four major classes of organic compounds, not just from one single class such as proteins, carbohydrates, lipids, or nucleic acids.