Explanation:

The concept of bond energy can help explain why anabolism requires energy input and catabolism releases energy.

Bond Energy:

Bond energy is the amount of energy required to break a bond. Different types of chemical bonds have different bond energies. For example, the bond between two atoms of hydrogen (H-H) has a bond energy of 436 kJ/mol, while the bond between two atoms of oxygen (O-O) has a bond energy of 498 kJ/mol.

Anabolism and Catabolism:

Anabolism is the process of building complex molecules from simpler ones, while catabolism is the process of breaking complex molecules down into simpler ones.

Anabolism:

In anabolism, new chemical bonds are formed between atoms to create more complex molecules. This process requires an input of energy because the new bonds that are formed have a higher bond energy than the bonds that were broken to create the simpler molecules.

For example, the process of photosynthesis is an anabolic process in which plants use energy from the sun to build glucose molecules from carbon dioxide and water. This process requires energy input because the carbon-oxygen and hydrogen-oxygen bonds in glucose have higher bond energies than the carbon-oxygen and hydrogen-oxygen bonds in carbon dioxide and water.

Catabolism:

In catabolism, existing chemical bonds are broken to release energy. This process releases energy because the bonds that are broken have a higher bond energy than the new bonds that are formed when simpler molecules are created.

For example, the process of cellular respiration is a catabolic process in which glucose molecules are broken down to release energy. The carbon-oxygen and hydrogen-oxygen bonds in glucose have higher bond energies than the carbon-oxygen and hydrogen-oxygen bonds in carbon dioxide and water, so the process of breaking down glucose releases energy.

Conclusion:

In summary, anabolism requires energy input because new chemical bonds are formed that have higher bond energies than the bonds that were broken to create the simpler molecules. Catabolism releases energy because existing chemical bonds are broken that have higher bond energies than the new bonds that are formed when simpler molecules are created.

For ex NACl na+ cl negative consume the energy when bond break so it is endothermic when bond make then these ions release energy so it is exothermic