Chapter 91

Apuntes

Chapter 9: Photosynthesis Ch 9.1 Energy and Life Key Questions 1 Why is ATP useful to cells? 2 What happens during the process of photosynthesis? Chemical Energy and ATP • Energy is the ability to do work • Without the ability to obtain and use energy by converting from one form to another, life would cease to exist • Light, heat, and electricity • In a lit candle, the energy lost is released as heat and light in the glow of the candle’s flame Storing Energy • All living cells store energy in the chemical bonds of certain compounds • ATP (adenosine triphosphate): compound used by cells to store and release energy • Adenine, a 5-carbon sugar called ribose, and three phosphate groups • The phosphate groups are the key to ATP’s ability to store and release energy Releasing Energy • The energy stored in ATP can be released when the third phosphate group is split off and released from the molecule forming ADP (adenine diphosphate) • ATP is the cell’s way of storing and releasing energy • Like a rechargeable battery • ATP can release and store energy by breaking and re- forming the bonds between its phosphate groups. This characteristic of ATP makes it excep...