210 likes | 219 Views
Explore the various pathways that cells use to release energy from compounds, both with and without oxygen. Learn how ATP is produced and the importance of glycolysis, Krebs Cycle, and electron transport. Discover the fascinating mechanisms behind ATP synthase and the role of creatine phosphate.
E N D
Cellular Respiration Chapter 9
Chemical Energy • There are many pathways cells can use to release energy from compounds • In the presence of oxygen there are many high-energy options • Without oxygen there are still options, but fewer
All those CALORIES!!! • One gram of sugar can be “burned” to produce 3811 calories of heat energy • One calorie is the amount of energy needed to raise the temperature of 1 gram of water 1 degree Celcius • Cells don’t actually “burn” glucose but release the energy slowly through cellular respiration
Cellular Respiration 6O2 + C6H12O6 6CO2 + H2O + Energy Oxygen + Carbon dioxide + water Glucose + ENERGY!!
ATP!!! • Adenosine triphosphate • When a cell has energy available it stores it by adding a third phosphate group onto ADP to make ATP • Breaking the bond of the third phosphate group on ATP releases energy
ENERGY!! ENERGY!!
Step 1: Glycolysis • Happens with or without oxygen • 2 ATP required to run Glycolysis • 4 ATP come out of the reaction • Glucose is broken in half into 2 molecules of pyruvic acid and a 3-carbon compound
Glucose Pyruvic Acid Pyruvic Acid 3 Carbon Compound Glycolysis
ATP! ATP! ATP! ATP! ATP! ATP! ATP Balance Glycolysis ATP production is small, but so fast that it can produce thousands of molecules of ATP in a few milliseconds
NADH • As Glycolysis runs, it passes extra electrons to NAD+ which produces NADH • When the cell has turned all of the NAD+ molecules into NADH there are no more electron receptors and Glycolysis can no longer continue
Aer sweet AER! Aerobic energetic reactions take place in the mitochondria to produce LOADS of ATP
Mr. Kreb and the Oranges • First compound formed in Krebs Cycle is citric acid • Begins when pyruvic acid enters the mitochondrion • Kreb’s Cycle produces all of the CO2 you will ever exhale from your body
Krebs Cycle • Pyruvate goes in • 4 NADH, 1 FADH2, 1 ATP, and 2 CO2 come out
Electron Transport • The Electron Transport chain received high energy molecules (charged with high energy electrons) from Mr. Kreb • Molecules are passed from receptor to receptor, stepping down the energy level and releasing electrons to carriers inside the mitochondrion.
E- Transport • At the end of the chain there is an enzyme that combines low energy electrons with hydrogen ions and oxygen to form water. • H+ ions are built up in the inner membrane through the transport process making it positively charged
E- Transport • H+ ions can be allowed to pass through protein channels in the cellular membrane turning the ATP synthases. • The movement of the H+ ions provides the energy to attach the third phosphate onto the ADP molecule and form ATP
ATP Synthase- Cell Turbine http://fig.cox.miami.edu/~cmallery/150/makeatp/makeatp.htm
F1 motor of ATP synthase uses the power of rotational motion to build ATP. Left conformation is the one connected with ADP binding. Right conformation is connected with ATP release. (computed @ rasmol)
http://upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Atp_synthase_pt.png/450px-Atp_synthase_pt.pnghttp://upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Atp_synthase_pt.png/450px-Atp_synthase_pt.png