Keystone Biology Review Bioenergetics

Bioenergetics  The role of plastids (i.e. chloroplasts) and mitochondria in energy transformations  Chloroplasts: An organelle found in plant cells and the cells of other eukaryotic photosynthetic organisms where photosynthesis occurs.  Mitochondria: A membrane ‐ bound organelle found in most eukaryotic cells; site of cellular respiration.

Bioenergetics  Photosynthesis: A process in which solar radiation is chemically captured by chlorophyll molecules and through a set of controlled chemical reactions resulting in the potential chemical energy in the bonds of carbohydrate molecules.  Carbon dioxide + water  glucose(sugar) + oxygen  Photosynthesis is carried out by plants and some bacteria

Bioenergetics  Cellular Respiration: A complex set of chemical reactions involving an energy transformation where potential chemical energy in the bonds of “food” molecules is released and partially captured in the bonds of adenosine triphosphate (ATP) molecules  glucose (sugar) + oxygen  carbon dioxide + water + ATP  Cellular respiration is carried out by pretty much all cells

Bioenergetics  Both include reactions that transform energy. Energy transformations involved:  Photosynthesis:  Light dependent reaction: uses sunlight, carbon dioxide, and water to make Oxygen and ATP.  Light independent reaction (Calvin cycle): uses ATP to make carbohydrates like glucose.  Cellular Respiration  Glycolysis: breaks down glucose into pyruvate and some ATP.  Krebs cycle: breaks down pyruvate into some ATP.  Electron transport chain: uses electron carriers from glycolysis and Krebs to make a lot of ATP.  How they are related: they are opposites of each other. Both processes are needed for living things to get energy.

Bioenergetics  Describe the role of ATP in biochemical reactions  ATP: A molecule that provides energy for cellular reactions and processes. ATP releases energy when one of its high ‐ energy bonds is broken to release a phosphate group.  It is made up of a ribose, adenine, and 3 phosphates.  It is formed during cell respiration by joining an ADP and a phosphate.  In order to release energy it breaks apart into an ADP and a phosphate.  Common source of energy in cells is ATP. It is a fast, short term source of energy.  ATP is the form of energy ultimately used by all living things. Anything a cell does (move, change, grow, produce, respond, etc.) requires ATP. Any question involving energy will likely include “ATP” in the answer. Any question involving ATP will likely include “energy” in the answer.

Video Review  Chloroplast Chloroplast

Video Review  Mitochondria Mitochondria

Video Review  Photosynthesis and Respiration Photosynthesis and Respiration

Video Review  Photosynthesis Photosynthesis

Video Review  Cellular Respiration Cellular Respiration

Video Review  ATP ATP