CellularRespiration - Cellular Respiration A.P. Biology...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Cellular Respiration A.P. Biology
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Energy Flows into an ecosystem as sunlight and leaves as heat Light energy ECOSYSTEM CO 2 + H 2 O Photosynthesis in chloroplasts Cellular respiration in mitochondria Organic molecules + O 2 ATP powers most cellular work Heat energ y Figure 9.2
Background image of page 2
Catabolic pathways yield energy by oxidizing organic fuels The breakdown of organic molecules is exergonic Fermentation Is a partial degradation of sugars that occurs without oxygen
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Catabolic pathways yield energy by oxidizing organic fuels Cellular respiration Is the most prevalent and efficient catabolic pathway Consumes oxygen and organic molecules such as glucose Yields ATP
Background image of page 4
Redox Reactions: Oxidation and Reduction Catabolic pathways yield energy Due to the transfer of electrons Redox reactions Transfer electrons from one reactant to another by oxidation and reduction Oxidation A substance loses electrons, or is oxidized Reduction A substance gains electrons, or is reduced
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
becomes oxidized (loses electron) becomes reduced (gains electron)
Background image of page 6
Some redox reactions Do not completely exchange electrons Change the degree of electron sharing in covalent bonds CH 4 H C O O O O O C Methane (reducing agent) Oxygen (oxidizing agent) Carbon dioxide Water + 2O 2 CO 2 + Energy + 2 H 2 O becomes oxidized becomes reduced Reactants Products Figure 9.3
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Oxidation of Organic Fuel Molecules During Cellular Respiration During cellular respiration Glucose is oxidized and oxygen is reduced C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + Energy becomes oxidized becomes reduced G = -686 kcal/mol
Background image of page 8
Step by step catabolism of glucose If electron transfer is not stepwise A large release of energy occurs As in the reaction of hydrogen and oxygen to form water (a) Uncontrolled reaction Free energy, G H 2 O Explosive release of heat and light energy Figure 9.5 A H 2 + 1 / 2 O 2
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
ETC The electron transport chain Passes electrons in a series of steps Uses the energy from the electron transfer to form ATP 2 H 1 / 2 O 2 (from food via NADH) 2 H + + 2 e 2 H + 2 e H 2 O 1 / 2 O 2 Controlled release of energy for synthesis of ATP ATP ATP ATP Electron transport chain Free energy, G (b) Cellular respiration + Figure 9.5 B
Background image of page 10
NAD – N icotinamide A denine D inucleotide (Electron Acceptor) Electrons from organic compounds Are usually 1 st transferred to NAD + , a coenzyme NAD + H O O O O O O O O O O P P CH 2 CH 2 HO OH H H HO OH HO H H N + C NH 2 H N H NH 2 N N Nicotinamide (oxidized form) NH 2 + 2[H] (from food) Dehydrogenase Reduction of NAD + Oxidation of NADH 2 e + 2 H + 2 e + H + NADH O H H N C + Nicotinamide (reduced form) N Figure 9.4 Dehydragen ase – removes 2 hydrogen atoms
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
NADH NADH, the reduced form of NAD + Passes the electrons to the electron transport chain Electrons are ultimately passed to a molecule of oxygen (
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 73

CellularRespiration - Cellular Respiration A.P. Biology...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online