55 terms

Energy- Cellular Respiration/Photosynthesis

Kinetic Energy
Energy of motion
Potential Energy
stored energy
First law of thermodynamics
Energy cannot be created or destroyed, it can only change forms
Second law of thermodynamics
Entropy of the universe always increases
Measure of disorder or randomness- can decrease by putting energy into it
converts solar energy into the chemical energy of a carbohydrate- Solar energy + 6CO2 +6H2O = C6H12O6 + 6O2. Organisms include plants, algae and certain bacteria.
Cellular respiration
C6H12O6 + 6CO2 = 6CO2 +6H2O
Adenosine Triphosphate- provides energy to cells for chemical reactions
Oxidation-Reduction reactions
Chemical reactions which involve a partial or complete transfer of electrons. Called redox reactions.
Oxidation Is Loss of elections, Reduction Is Gain of electrons / Loss of Electrons is Oxidation, Gain of Electrons is Reduction
Electron Carriers
enzyme that adds P directly onto ADP to make ATP- used for quick energy, anaerobic, occurs in cytoplasm
The breakdown of glucose by the removal of hydrogens- used for short term energy production, anaerobic, occurs in cytoplasm- produces 2 molecules of pyruvate
ATP used to add phosphates to glucose
6 C unit split into two 3 C units
Energy recovery
Production of ATP & NADH
Inputs of glycolysis
Glucose, 2 NAD+, 2 ATP, 4 ADP + 2P
Outputs of glycolysis
2 Pyruvate, 2 NADH, 2 ATP (net gain)
Pyruvate- oxygen absent
Fermentation in cytoplasm
Pyruvate- oxygen present
Kreb's cycle in mitochondria
regenerates NAD+ from NADH
Lactic Acid
What builds up in underused muscles
Lactic Acid Fermentation
Animal cells. Pyruvic acid is converted to 3 carbon lactic acid. Diffuses into blood, transported to liver and converted back to pyruvic acid when oxygen is present.
Alcoholic fermentation
Plant cells and yeast convert pyruvic acid to ethyl alcohol (ethanol) and CO2
Transition Reaction
Occurs in the matrix, pyruvate combines with coenzyme A (CoA) to produce acetyl CoA. 2 NAD is reduced to NADH + H. 2 CO2 is released.
Cellular Respiration
used for long term energy production, aerobic, occurs in mitochondria matrix, can use glucose, fats or proteins as fuel.
Krebs Cycle
Citric Acid cycle- Acetyl CoA combines with 4C. 6C is oxidized as NAD reduced to NADH, CO2 removed. 5C is oxidized as NAD reduced to NADH, another CO2 is formed, ATP is generated. 4C is oxidized as FAD and NAD reduced to FADH2 and NADH. 4C molecule.
Output of Krebs Cycle per glucose molecule
6 NADH, 2 FADH2, 2 ATP, 4 CO2
Electron Carriers
Store energy
Electron transport proteins
membrane proteins
H+ pumps
membrane protein to pump a proton against concentration gradient
Final electron acceptor
ATP Synthase
protein that uses energy released by movement of protons down concentration gradient to make ATP
ATP yielded by each NADH
ATP yielded by each FADH2
The process by which light energy is converted into stored chemical energy
Distance between 2 peaks
Small wavelength
higher energy
Large wavelength
lower energy
absorb different wavelengths of light from chlorophyll. They appear red, yellow and orange to us.
Fluid filled region
Disk like sac
Stack of thylakoids
found in thylakoid membrane, absorbs red and blue.
Light dependent reactions step 1
Light excites e- in chlorophyll of photosystem II
Light dependent reactions step 2
e- move to an e- acceptor
Light dependent reactions step 3
e- transferred along ETC
Light dependent reactions step 4
Light excites e- in photosystem I and move to an e- acceptor. e- are replaced by e- from photosystem II.
Light dependent reactions step 5
e- are transported along another ETC and combine with NADP+ to make NADPH
Restoring photosystem II
enzyme in thylakoid splits water into protons, electrons and oxygen. Electrons replace photosystem II, protons are left inside thylakoid, oxygen diffuses.
build up of concentration gradient of protons (H+)
Calvin Cycle
Light independent reactions. Occurs in stroma, also known as carbon fixation.
Calvin cycle step 1
CO2 combines with RuBP to form 2-3 carbon PGA
Calvin cycle step 2
PGA is converted to PGAL, through release of phosphate and a proton from NADPH
Calvin cycle step 3
Most PGAL is converted back to RuBP, some is used to make organic compounds.