Which substance is the most direct source of energy that an animal cel uses for synthesis materials?

The most direct source of energy that an animal cell uses for synthesizing materials is adenosine triphosphate (ATP). ATP is a small molecule that contains three phosphate groups attached to a ribose sugar and an adenine nitrogenous base. It is considered the universal energy currency of cells because it is the primary energy carrier that provides the energy required for various cellular processes, including the synthesis of macromolecules such as proteins, nucleic acids, and lipids.

ATP is produced in the mitochondria through cellular respiration, where organic molecules such as glucose are broken down and the energy released is captured and stored in the form of ATP. Each ATP molecule contains two high-energy phosphate bonds that, when broken, release energy that can be used to drive endergonic reactions, including those involved in synthesis and other energy-consuming processes.

As ATP is hydrolyzed to ADP (adenosine diphosphate), the released energy is harnessed to drive various cellular activities. For instance, during protein synthesis, ATP is utilized to elongate the growing polypeptide chain by catalyzing the addition of amino acids to the chain. Similarly, in nucleic acid synthesis, ATP provides energy for the polymerization of nucleotides during DNA and RNA synthesis.

Therefore, ATP serves as the most direct and readily available source of energy that animal cells use for synthesis materials and other energy-demanding processes within the cell.