Chapter 9 | Cellular respiration anf fermentation

Cellular respiration

How cells obtain the energy needed to carry out functions of life from organic molecules

• is how cells break down food energy to create ATP

Cellular respiration bonds

Energy is stored in the bonds of organic molecules!

• which is why catabolic archways are used to release the energy out of the bonds (endergonic)

Cellular respiration

Presence of O2, more efficient

Fermentation (single celled)

Absence of O2, less efficient

Cellular respiration equation words

Glucose + oxygen= water + energy + carbon dioxide

Cellular respiration equation numbers

C6H12O6 + 6 (CO2) → 6 (CO2) + 6 (H2O) + ATP

Energy and bonds

Cells release energy through oxidation

• one bond at a time, large cells cant be oxidized all at once

Oxidation

LEO

• Lose electrons = Oxidation

Reduction

GER

• Gain Electrons = reduction

Glucose oxidized

Cells transfer the potential energy contained in the bonds of glucose to electron carriers

• so the process of oxidation and reduction is losing and receiving electrons to pass down that energy

NAD+ reduced to

NADH

• gains two electrons and one hydrogen

FAD reduced to

FADH2

Glycosis

Glucose oxidized to pyruvate

• (1) 6-carbon molecule (glucose) oxidized (split) into (2) 3-carbon molecules (pyruvates)

Pyruvate

3 carbon molecules, split from glucose!

Glycosis What goes in

• 1 glucose

• 2 ATP

• 2NAD+

Glycosis What comes out

4 ATP (2 NET ATP!)

2 pyruvates

2 NADH (ETC)

Glycosis When

1st phase

Glycosis Where

Cytosol of cell

Glycosis Who main

Glucose

Glycosis Why

Oxidize glucose into pyruvate and create NADH electron carriers

Pyruvate oxidation

Pyruvate broken down (oxidized) and bonds with coenzyme A to create Acetyl CoA

Keep in mind this process happens twice per glucose!

Pyruvate oxidation What goes in

Keep in mind this process happens twice per glucose!

In total:

2 pyruvate (from glycosis)

2 Coenzyme A

2 NAD+

Pyruvate oxidation what comes out

• 2 Acetyl-CoA (citric acid cycle)

• 2 NADH (ETC)

• 2 CO2 (we exhale)

Pyruvate oxidation When

After glycolysis (2nd step)

Pyruvate oxidation where

In mitochondrial matrix

Pyruvate oxidation Who

Pyruvates oxidized

Pyruvate oxidation Why

Oxidize 3-carbon pyruvates into (2) 2-carbon acetyl-CoA and create more NADH electron carriers

Citric acid cycle

One cycle per Acetyl CoA (2 Acetyl CoA’s per glucose!)

Acetyl-CoA (2 carbons) enters the cycle and combines with oxaloacetate (4 carbons).

• 2C + 4C = citrate (6 carbons).

• First oxidation: releases NADH and CO2

• Second oxidation: releases CO2

• Last four turn into ATP, FADH2, and NADH

Citric acid cycle when

After pyruvate oxidation (3rd step)

Citric acid cycle where

Still in mitochondrial matrix

Citric acid cycle Who main

1 Acetyl coA

Citric acid cycle Why

Oxidize 2-carbon Acetyl to 1 carbon CO2

Oxidative phosphorylation

Combination of 2 process, electron transport chain and chemists

Etc where

Mitochondrial inner membrane

Etc who

NADH and FADH2

Chemiosmosis where

Mitochondrial intermembrane

Chemiomosis who main

H+ ions

NADH

Deposits electrons at complex I

FADH2

eposits electrons at complex II

ETC what goes in

This is per molecule of glucose! (So like all together)

• 10 NADH (from glycolysis, pyruvate ox, AC-6)

• 2 FADH2 (from CAC)

• O2 from breathing

ETC what comes out

26-28 ATP

Water

ETC process

• Electrons fall from 1 electron carriers to another, gives freee energy and its used to pump out H+ ions into the intermembrane space

Electron protein complexes

Embedded into mitochondrial inner membrane (takes electrons stored in NAD+ and FADH2 and pass them from one complex to another)

• oxidation reduction phases

• 4 (I-IV)

• 2 shuttles (ubiquinone and cytochrome)

• Bounces back and forth

Chemiomosis and ATP synthase

The energy flow of H+ down into the synthase into matrix to help make ATD into ATP!

Fermentation

Only makes 2 ATP

Cycle repeats

Less efficient

Alcohol fermentation

Pyruvate is converted into ethanol

• pyruvate→2 acetaldehyde→alcohol fermentation→2 ethanol

Lactic acid fermentation

Pyruvate converted to lactate

pyruvate→2 lactate

Oxygen isnt keeping up with cellular respiration so like muscle cramp is a lactate acid buildup

Cellular pistons

Some poisons interrupt or block one/more stages of cellular respiration

Rotenone

Disrupts complex I to ubiqionone

Etc

Cyanide

Disrupts cytochrome c complex

Etc

Carbon monoxide

Prevents O2 from being final electron acceptor

Etc

Oligomycin

Blocks atp synthase

Chem

DNP

Allows H+ to leak into matrix

Chem