Biol chapter 9 cell respiration

Cell respiration

Getting the chemical entertainment from fuel molecules, consuming oxygen and producing CO2.

ΔG for complete combustion of glucose

-686kcal/mol

Cell respiration

Getting the chemical entertainment from fuel molecules, consuming oxygen and producing CO2.

ΔG for complete combustion of glucose

-686kcal/mol

Cellular respiration is highly exergonic and drive that ___ formation of many ATP molecules

Endergonic

Redox reactions

Oxidation reduction reactions are when electrons are passed from one molecule to another

Oxidation

The loss of electrons

Reduction

The gaining of electrons

Oxidation and reduction take place at

The same time

The reduced compound is the

Oxidizing agent

The oxidized compound is the

Reducing agent

In cellular respiration, glucose

Oxidizes and loses hydrogens

In cellular respiration, oxygen

Is reduced and gains hydrogens

Glucose and oxygen go into cellular respiration, and

Carbon dioxide and water are produced

NAD

An electron shuttle that can reduce or oxidize metabolites and carry electrons between reactions during respiration

Substrate level phosphorylation

Enzymes transfer a phosphate group from an organic substrate to ADP to produce ATP.

Least efficient form of ATP production

Oxidative phosphorylation

ATP production that uses the energy harnessed from the redox reactions in the electron transport chain

Most efficient form of ATP production

Glycolysis

Breaking down of glucose into two pyruvates

Pyruvates

An intermediate in cellular respiration

Where glycolysis occurs

In the cytoplasm

Two phases of glycolysis

Energy investment and energy harvest

Glycolysis inputs

6c glucose, 2NAD+, 2ATP, 4ADP and 4 P

Outputs

2 3c pyruvates , 2 NADH, 2ADP, 4ATP

Glycolysis has a net gain ATP of

2

2 pathways of glycolysis

The 3c pyruvates will either go to cellular respiration or fermentation

Cellular respiration is

Aerobic and completed oxidation

How many ATP does cellular respiration produce per glucose

32 ATP

Fermentation is

Anaerobic and incomplete oxidation

Fermentation waste products are

Lactic acid or ethanol and carbon dioxide

Fermentation produces how many ATP per glucose

2 ATP

Energy pathway in eukaryotic cells that takes place outside the mitochondria

Glycolysis and fermentation

Energy pathway in eukaryotes inside the mitochondria

The respiratory membrane in the inner membrane and the citric acid cycle and private oxidation in the matrix

Energy pathways in prokaryotes that take place in the cytoplasm

Glycolysis, fermentation, and the citric acid cycle

Energy pathways that take place on the plasmas membrane in prokaryotic cells

Pyruvates oxidation and respiratory chain

Cristae

Inner membrane sacs joined by short tubes in the mitochondria

Matrix

The free space in the mitochondria

Interspace membrane

Space between inter and outer membrane of the mitochondria

Before the citric acid cycle can begin, the private must be converted to

Acetyl CoA

The citric acid cycle ( Krebs cycle) takes place in the

Mitochondrial matrix

Citric acid cycle process

NADH and FADH2 capture electrons from the conversion of acetyl- CoA to citric acid. Substrate level phosphorylation

How many times does the citric acid cycle turn for every glucose molecule

2 times

Citric acid cycle inputs

2 2c acetyl groups, 6NAD+, 2FAD, 2ADP and 2 P

Citric acid cycle Outputs

4CO2, 6 NADH, 2FADH2, 2ATP

Where does the electron transport chain take place In the mitochondria?

The cristae

How does the electron transport chain produce energy

Passing electrons downhill to a series of electrons accepting enzymes

The is the final acceptor of the electron transport chain

Oxygen

ATP synthase

And enzyme powered by protons

Processes in the electron transport chain that produces ATP

Oxidative phosphorlyation and chemiosmosis

Chemiosmosis

Users entry stored in hydrogen ions (protons) gradient to drive cellular work( synthesis of ATP)

ATP synthase location

Embedded in the mitochondrial membrane

How does ATP synthase produce ATP

It uses ADP and the flow of protons released in the electron transport chain. H+ ions flow down their gradient and bind to the rotor of the ATP synthase enzyme changing the rotors shape and causing it to spin

Glycolysis

Occurs in the cytoplasm

Breaks down glucose into 2 pyruvates

Occurs in 2 phases: energy investment and energy harvest.

Glycolysis input

6c glucose , 2 NAD+, 2ATP, 4 ADP and 4P

Glycolysis outputs

2(3c) pyruvates , 2 NADH, 2 ADP, 4 ATP

Glycolysis net gain ATP

2

If oxygen is not available then ATP can only be produced via

Glycolysis

Fermentation

Glycolysis pathway that regenerates NAD+ so that glycolysis can continue,

Lactate fermentation

Lactate ( NAD+)

Alcoholic fermentation

Ethyl alcohol (CO2) and NAD+

Both alcoholic fermentation and lactate fermentation yield a net of how many ATP

2

How does fermentation work

Recreates NAD+ by transferring electrons from NADH to pyruvates or its derivatives

Polysaccharides are hydrolyzed into

Glucose, which enters glycolysis and cellular respiration

Lipids are broken into

Glycerol, which can be used as an intermediate in glycolysis and the fatty acids become acetyl CoA

Proteins are hydrolyzed into

Amino Acids, feed into glycolysis or citric acid cycle depending on the amino acid

Gluconeogenesis

Glucose formed form the citric acid stacks and glycolysis intermediates

How are catabolism and anabolism regulated

Through negative and positive feed back controls

Concentrations of biochemical molecules like glucose , should remain

Constant

Glycolysis , the citric acid cycle, and the respiratory chain are subject to

Allosteric regulation of key enzymes

Phosphofructokinase

Glycolysis enzyme that is inhibited by ATP

Isocitrate Dehydrogenase

Citric acid cycle enzyme inhibited by NADH+, H+, and ATP