Chapter 9

the versatility of catabolism

-Catabolic pathways funnel electrons from many kinds of organic molecules into cellular respiration -Glycolysis accepts a wide range of carbohydrates -Proteins must be digested to amino acids; amino groups can feed glycolysis or the citric acid cycle - energy can be extracted by only biological molecules

Concept 9.1: Catabolic pathways yield energy by oxidizing organic fuels

-catabolic pathways release stored energy by breaking down complex molecules - electron transfer plays a major roles in these pathways - these processes are central to cellular respiration ..

energy coupling

-photosynthesis generates O2. and organic molecules; are used in cellular respiration -cells use chemical energy stored in organic molecules to generate ATP, which powers work

The Principle of Redox

Chemical reactions that transfer electrons between reactants are called oxidation-reduction reactions, or redox reactions - in oxidation, a substance loses electrons or is oxidized - in reduction, a substance gains electrons or its reduced (the amount of positive charged is reduced)

The Pathway of Electron Transport... series of protein diagram

example; the game of hot potatoe take energy- pass along-take energy- pass along

entropy example

glucose is like $100, its alot but hard to spend ATP is like 5 twenty dollar bills; can be spent more easily cellular respiration cashes in a larger denomination of energy (glucose) for the smaller change of many molecules of ATP

Concept 9.2: Glycolysis harvests chemical energy by oxidizing glucose to pyruvate

glycolysis " sugar spitting" breaks down glucose into 2 molecules of pyruvate - glycolysis occurs in the cytoplasm and has 2 major phases 1. energy investment phase 2. energy payoff ohase - glycolysis occurs whether or not o2 is present ( anaerobic or aerobic)

Concept 9.5: Fermentation and anaerobic respiration enable cells to produce ATP without the use of oxygen..... ANOTHER CONCEPT no oxygen-= fermentation

glycolysis coupoles with anaerobic respiration of fermentation to produce atp . has the electrton transport chain, but not the same

catabolic pathways and production of ATP 2 major forms

the breakdown of organic molecules is exergonic... 1. fermentation- is a partial degradation of sugars that occurs w/o o2 2. aerobic respiration - consumes organic molecules and o2 and yields ATP

Chemoismosis: the energy coupling mechanism pt 2

the h+ gradient is referred to as a proton-motive force, emphasizing its capacity to do work

glycolysis in cytosol. electron transport train

the process that generates almost 90% of the ATP is called oxidation phosphorylation (bc of redox reaction)

catabolic pathways and production of ATP pt 2

.... anaerobic respiration is similiar to aerobic respiration but consumes compounds other than o2 3. cellular respiration includes both aerobic and anaerobic respiration but is often used to refer to aerobic respiration -..although carbohydrates fats and proteins are all consumed as fuel, it is helpful to trace cellular respiration w/ the sugar glucose

glycolysis results = what? breakdown in 2 pyruvate where? in cytoplasm now ? 2 pyruvate , 2 atp, 2 naha

..... after pyruvate is oxidized , the citric acid cycle complete the energy- yielding oxidation of organic molecules

2 types of fermentation

1. alcohol ferm- pryuvate is convereted to ethanol in 2 steps - the first step releases CO2 , from pryuvate - the second step produces NAD and ethanol 2. lactic ferm- pryuvate is reduced by NADH froming NAD+ and lactate as end products w/ no release of CO2 humans mucles cells use lactic acid ferm. to generate ATP during strenuous exercise when o2 is scarece

the stages of cellular respiration: preview ... is it aerobic 3 stages

1. glycolysis- breaks down glucose into two molecules of pyruvate ( all cells do this; an ancient pathway) 2. the citric acid cycle- complete the breakdown of glucose 3. oxidative phosphorylation- accounts for most of the ATP synthesis .. aka electron transport a.process b. location c. output

Life is work

Living cells require energy from outside sources - the work of the cell includes assembling polymers, membrane transport , moving, and reproducing - energy flows into an ecosystem as sunlight and leaves as heat - the chemical elements essentials to life are recycled

Concept 9.4: During oxidative phosphorylation, chemiosmosis couples electron transport to ATP synthesis

NADH and FADH account for the most of the energy extracted from food these two electrons carriers donate electrons to the electron transport chain, which powers ATP synthesis via oxidation phosphorylation

lactic acid fermentation and alcohol fermentation

The conversion of pyruvate to lactate with no release of carbon dioxide.

The Pathway of Electron Transport... series of protein

The electron transport chain is in the inner membrane (cristae) of the mitochondrion Most of the chain's components are proteins, which exist in multiprotein complexes The carriers alternate reduced and oxidized states as they accept and donate electrons Electrons drop in free energy as they go down the chain and are finally passed to O2, forming H2O

Redox Reactions: Oxidation and Reduction

The transfer of electrons during chemical reactions releases energy stored in organic molecules This released energy is ultimately used to synthesize ATP "leo the lion says ger"

chapter 9

cellular respiration and fermentation

Comparing Fermentation with Anaerobic and Aerobic Respiration

cellular respiration produces 32 ATP per glucose molecules, fermentation produces 2 ATP per glucose molecules 1. obligate anaerobic carryout fermentation or anaerobic respiration and cannot survive in the presence of o2 2. yeast and many bacteria are facultative anaerobes, meaning that they can survive using either fermentation or cellular respiration ... (both anaerobic. and aerobic)

Chemoismosis: the energy coupling mechanism

this is an example cvhemoismosis, the use of energy in a H+ gradient to drive cellular work .. diffusion of h+ thru concentration gradient h+ then moves down its concentration gradient back across the memebrane, passing through the protein complex ATP synthesis

the. citric acid cycle ( or called krebs cycle) the cycle oxidizes organic fuel derived from pyruvate, generating 1 atp, 3 nadh , and 1 fadh ....PER TURN ..... IT DOES 2 TURN CYCLES

what? breakdown of pyruvate where? matrix of mittochandria results? 2 atp, 6 nadh, 2 fadh