Biological systems need energy! To do “work” Chemical activities Growth Movement Reproduction Repair ? Stored in CHEMICAL BONDS

Chemical Energy………….. Stored in? Food (Plant or Animal) Made by Producers in? Photosynthesis as? Glucose sugar Energy is released? Respiration, breaks the chemical bonds

ADP in cell P ATP Stored energy in glucose bonds + + Respiration Forms so cell can do work = Release of food energy

ATP cell energy High energy molecule Supplies cell energy ATP cycles from ADP by addition of a high energy phosphate from the release of chemical energy in respiration

Adenosine Triphosphate (ATP)

ADP to ATP cycle ADP=di phosphate ATP= tri phosphate ATP makes a muscle work High energy ATP -P after cell work ADP in cell

Burning versus Respiration Activated by friction Heat Energy Light Energy Carbon Dioxide Oxygen Respiration: Activated by enzymes Heat Energy ATP cell energy Carbon Dioxide Oxygen

Oxidation and Reduction Oxidation is the loss of electrons by an atom and reduction is the gain of electrons by an atom. Oxidation and reduction must occur at the same time in the chemical reaction and the loss or gain of electrons forms ions out of the atoms

Electron Acceptors Electron acceptors or carriers are an important part of cellular respiration. They are the molecules that accept the high-energy electrons or hydrogen ions and transfer them along the biochemical pathway. Examples include NAD+ and FAD. Each of these can carry two high-energy electrons and two hydrogen ions, thus they are reduced. they are converted to NADH and FADH2, while accepting the energy stored in the electrons and protons

Cellular Respiration………. Breakdown of Food Occurs in the Mitochondria of Plant & Animal Cells Produces? ATP cell energy CO2 gas waste

Two Types of Respiration Anaerobic or fermentation – does not require oxygen. Makes 2 ATP.

Aerobic- requires oxygen and makes a lot more energy. Makes 36 ATP.

Cellular Respiration

Glucose is split into two molecules called PGAL by the addition of 2 ATP. PGAL is then oxidized forming pyruvic acid. Energy is released forming 2 ATP and the 2 electrons lost convert NAD into NADH.

Fermentation After glycolysis, anaerobic respiration or fermentation takes the following turn. The pyruvic acid is changed into ethyl alcohol and carbon dioxide or lactic acid or some other compound depending on the type of bacteria.

Aerobic Respiration Occurs in cristae of mitochondria Pyruvic acid is converted into acetyl CoA by breaking down into carbon dioxide, NADH, and a two carbon compound, which combines with a coenzyme, called CoA (coenzyme A), to form acetyl CoA. These then go into the Kreb’s Cycle

Krebs Cycle

Electron Transport Chain After the Krebs cycle is finished the NADH and FADH2 carry the energy stored in their hydrogen atoms and use it to make ATPs in the inner membrane of the mitochondria. The process is called electron transport chain(ETC)

Electron Transport Chain a series of oxidation and reduction reactions take place where electrons are passed from one compound to another until eventually, free oxygen accepts 2 H+s and a pair of electrons to form water

The water may be used by the cell or excreted as waste The water may be used by the cell or excreted as waste. In most cells 32 ATPs are produced by the ETC for each molecule of glucose. Add this to the 2 ATPs from glycolysis and the 2 ATPs from the Krebs cycle and you have 36 ATP total.

Respiration Equation >>>>> food + oxygen + H20 = ATP+ CO2 +H20 C6H1206 + 6 O2 + 6 H20 = 36 ATP+ 6 CO2 + 12 H20