Compare and contrast cellular respiration and combustion.?

Question

What do they use to start? What makes them go? What do they release as energy? What do they release as by-products?

Answer 1

Assuming you mean hydrocarbon combustion:
They both use up a carbohydrate and oxygen
They both produce energy and carbon dioxide and water
They are both chemical reactions

hydrocarbon combustion releases energy in the form of heat and light. It is started with an ignition source. It is a Hydrocarbon combustion chemical reaction.

cellular respiration releases energy in the form of ATP (chemical potential energy). It is started with ATP being used to break the bonds of the fuel source*. It is a REDOX reaction**.

*- the fuel source is commonly glucose but can also be amino acids or fatty acids.
**- cellular respiration is a series of chemical reactions (this may also be used as a diffrence between the 2) over all it appears as a REDOX reaction because it is the oxidation of energy molecules.

Answer 2

Remember that these reactions have negative delta G, which means the products are more energetically favorible than the reactants. So, the products are more stable. The key to understanding the difference between the two processes is ENZYMES!!!! Enzymes make respiration incredibly efficient compared to a combustion engine lets say. Our cells then use enzyme complexes and electron carriers to create an proton gradient (using hydrogen ions), and the proton-motive force of the protons returning to the area of lower concentration, creates free energy, which is harvested by formation of ATP molecules, where said energy is stored.

Answer 3

They are opposites. In photosynthesis, water molecules are split and the oxygen from the water is released to the atmosphere. The plant then splits carbon dioxide into C and O the plant then attaches the hydrogen from the water to the oxygen. From that the plant makes two things. First, it makes water. Second, through chlorophyll, the plant bonds the hydrogen to the oxygen AND then bonds the carbon back on which creates C6H12O6 or glucose and, it is in the glucose that sunlight energy is stored as chemical (or food) energy. In cellular respiration (CR), in the cytoplasm and the mitochondria, glucose is broken apart, the chemical energy that held it together is then used by the cell for the rephosporlation of ADP and P back into ATP. This breakdown of glucose occurs anaerobically in the cytoplasm by enzymes. However, a second step of CR also occurs in the mitochondria where oxygen (it came from the plant breaking down water) is used (therefore called aerobic respiration) to break apart one of the waste products of anaerobic respiration, which then releases enough energy to rephosphorlate 36 molecules of ATP. The by-products of CR are carbon dioxide and water which then goes back to the plant so it can go through photosynthesis ... THUS, Everything just keeps getting re-cycled and remains in balance.