Cellular Respiration

Pages: 98 to 103 and 357 to 368

Understandings - Basics

Cell respiration is the controlled release of energy from organic compounds to produce ATP

ATP from cell respiration is immediately available as a source of energy in the cell

Aerobic cell respiration requires oxygen and gives a large yield of ATP from glucose

Anaerobic cell respiration gives a small yield of ATP from glucose

Cell respiration involves the oxidation and reduction of electron carriers

Basic Vocabulary

Aerobic AnaerobicCatabolicAnabolicOxidationReduction

Oxidation and Reduction

Oxidation Reduction

Loss of electrons Gain of electrons

Gain of oxygen Loss of oxygen

Loss of hydrogen Gain of hydrogen

Results in many C-O bonds Results in many C-H bonds

Lower potential energy Higher potential energy

OIL RIG or LEO goes GER

Oxidation and Reduction

C6H12O6 + 6O2  6CO2 + 6H2O + Energy (as ATP)

What is oxidized? glucose

What is reduced? oxygen

Overall Redox reaction

Aerobic and Anaerobic Respiration

Both begin with glucose entering glycolysis Takes place in cytoplasm

Requires 2 ATP

Glucose is converted into 2 pyruvate

Produces 4 ATP

Net yield of 2 ATP

Alcoholic Fermentation

Pyruvate enters into anaerobic respiration when no oxygen is available No more ATP is created

Pyruvate becomes ethanol by losing carbon dioxide

pyruvate

ethanolpyruvate

glucoseethanol

CO2

CO2

Fermentation

What type of organism uses alcoholic fermentation?

Where is alcoholic fermentation seen in our daily lives?

How does fermentation apply to animals?

What is produced? Does it just continue to build up?

Lactic Acid Fermentation

pyruvate

Lactatepyruvate

glucose

Lactate

Application

Use of anaerobic cell respiration in yeast to produce ethanol and carbon dioxide in baking

Lactate production in humans when anaerobic respiration is used to maximize the power of muscle contractions

Anaerobic respiration Bozeman: https://www.youtube.com/watch?v=cDC29iBxb3w

Aerobic Respiration

Glycolysis: Glucose to Pyruvate

Linking Reaction: Pyruvate loses CO2 and combines with coenzyme A to create acetyl-CoA

Krebs Cycle: Acetyl-CoA to Acetyl-CoA

ETC: NADH and FADH to ATP

Aerobic Respiration

How much ATP is produced in each part of the process?Glycolysis: 2Krebs Cycle: 2Electron Transport Chain with the chemiosmosis: 32

What is chemiosmosis?

Understandings - Glycolysis

Phosphorylation of molecules make them less stable

In glycolysis, glucose is converted to pyruvate in the cytoplasm

Glycolysis gives a small net gain of ATP without the use of oxygen

In aerobic cell respiration pyruvate is decarboxylated and oxidized, and converted into acetyl compound attached to coenzyme A to form acetyl coenzyme A in the link reaction

Glycolysis

Glycolysis

(1) 6-carbon glucose

(1) Fructose-1,6 - bisphosphate

(2) ATP (2) ADP

(2) glyceraldehyde – 3 - phosphate

P P

PP

lysis

PPPP

(2) 3 carbon compound

(2) pyruvate

(2) NAD+ (2) NADH

(4) ADP (4) ATP

Glycolysis Summary

2 ATP used

4 ATPS produced

2 net ATP produced

2 molecules of NADH produced

2 pyruvate molecules produced at end of pathway

Occurs in the cytoplasm

Controlled by enzymes – feedback inhibition blocks the first enzyme pathway if ATP is high

Activity Time

Cellular Respiration POGILS

LAB TIME

Analysis of results from experiments involving measurement of respiration rates in germinating seeds or invertebrates using a respirometer – LAB TIME!

Understandings – Krebs

In the Krebs cycle, the oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD

Analysis of diagrams of the pathways of aerobic respiration to deduce where decarboxylation and oxidation reaction occurs

The Link Reaction

What did glycolysis just create?

Where are we in the cell?

Where do we need to go in the cell?

What do we need to become in order to start the Krebs Cycle?

The Link Reaction

The Link Reaction

Controlled by enzymes

Decarboxylation occurs

Oxidation Reduction occurs

Acetyl CoA can be stored as fats What is the benefit of this?

When does this occur?

Krebs Cycle

Also known as the tricarboxylic acid cycle

1. Acetyl CoA combines with oxaloacetate to make citrate

2. Citrate gets decarboxylated and oxidized to a 5C molecule

3. 5C is decarboxylated and oxidized to 4C

4. 4C is Oxidized into oxaloacetate

Krebs Cycle Summary

Two “turns” of the cycle for on glucose molecule

2 ATP per glucose

6 NADH produced

2 FADH2 produced

4 molecules of CO2 How many have been produced so far?

What is the significance of this number?

Time for Oxidative Phosphorylation

POGIL TIME

Understandings - ETC

Transfer of electrons between carriers in the electron transport chain is the membrane of the cristae is coupled to proton pumping

In chemiosmosis protons diffuse through ATP synthase to generate ATP

Oxygen is needed to bind with the free protons to form water to maintain the hydrogen gradient, resulting in the formation of water

Video Time

Crash Course: https://www.youtube.com/watch?v=00jbG_cfGuQ

Bozeman: https://www.youtube.com/watch?v=Gh2P5CmCC0M

Understandings - Mitochondria

The structure of the mitochondria is adapted to the function it performs

Electron tomography used to produce images of active mitochondria

Skill: Annotation of a diagram of a mitochondria to indicate the adaptations to its functions