What macromolecules is the main source of energy for all living things?

Answer 1

A macromolecule is, essentially, defined as a very large molecule, usually produced as a product of polymerization through dehydration synthesis reactions. Biologically significant macromolecules are generally classified into four distinct groups: carbohydrates, proteins, nucleic acids, and lipids. Carbohydrates are composed of monosaccharides (simple sugars), either singly or polymerized (in which case they would be classified as polysaccharides or complex carbohydrates). Proteins are polypeptides with a function. Stating a protein is simply a polypeptide is as inconceivably erroneous as stating (a-b)2 equals a2 + b2, which it conspicuously is not! For example, human hemoglobin is composed of four heme group polypeptides, each of which independently would not function as when collectively structured. Without this completed quaternary structure, the hemoglobin would not function properly. A polypeptide is a polymer of amino acids. Amino acids are molecules composed of an amino group, R-variable group (which determines several characteristics of that amino acid), and a carboxyl group. Bonds between amino acids are called peptide bonds. Nucleic acids are polymers constructed from monomers called nucleotides. A nucleotide is composed of a phosphate group, deoxyribose, and a nitrogenous base (thymine, guanine, adenine, cytosine, and uracil, however, uracil is not found in deoxyribosenucleic acid). Lipids (yum!) are organic polymers insoluble in water, as a consequence of nonpolar structure; they are hydrophobic, unless one is considering phospholipids. As for the question (it was necessary to establish a fundamental understanding before proceeding), it depends on how one is considering "energy," as there are several different levels of energy organization. For example, considering metabolic activity would be different than considering biological entities as a whole. Essentially, the base of all energy is glyceraldehyde 3 phosphate, which is however considered a simple sugar yet used to produce a variety of other organic compounds needed for biological entities. Glyceraldehyde 3 phosphate (often abbreviated G3P) is produced during the Calvin cycle of photosynthesis. G3P is later processed to form other necessary materials such as isomers of C6H12O6. C6H12O6 for example is necessary for cellular respiration of all organisms. However, for other later metabolic activities, the main source of energy is adenosine triphosphate, a nucleic acid (the highly temperamental, unstable phosphate bonds due to the mutual negative charge of phosphates provides the energy.) Yet in ecology, the gross primary productivity, or amount of solar energy that is converted into biomass by the producers, is most fundamentally and universally measured by the amount of G3P produced, (which actually reflects the total amount of carbon fixation occurring, yet such is not a macromolecule, more so a process.) Thus, determining what macromolecule(s) is (are) the main source of energy is dependent upon how or at what energy organization level you are contemplating. Generally, nevertheless, one could confidently state carbohydrates such as isomers of (the simple sugar) C6H12O6 (for example glucose, fructose, galactose, ect.) or complex carbohydrates such as starch or glycogen produced by further processing of glyceraldehyde 3 phosphate as well as the nucleic acid adenosine triphosphate are the most fundamental energy-rich macromolecules used by biological entities. Remember, nonetheless, all energy essentially used by biological entities is dependent upon electrons and thusly chromodynamics of quarks, yet such is hardly a macromolecule.

-A soon to be AP Biology student. Thus, I suggest independent research with subsequent verification of sources would be prudent as I am not an expert. Immense credit is provided to Mr. McGee, a most superior teacher, one whose unfathomable reverence is justly deserved. Also, please note: the above is a, hopefully, succinct overview, lacking many structural, chemical, and functional details which have been excluded for brevity. Also, I hope grammatical and spelling flaws are minimal. If the latter is excessive, I apologize. Different interpretations are as well possible. For example, some biologists argue the importance of anatomical structure of an organism to its life cycle with subsequent points subtracted for deemed irrelevance on free response questions regarding assessments.

Answer 2

glucose