Cell Respiration Textbook: Biology Chapter 9: p.220

Respiration

Respiration- process that releases energy by breaking down food molecules.

2 Types of Cellular Respiration

aerobic and

anaerobic

Aerobic respiration- with oxygen Anerobic respiration- without oxygen

Cellular Respiration

Equation: C6H12O6 + O2 CO2 + H2O + Energy (ATP) glucose + oxygen carbon dioxide +

water + energy

Location for Cellular Respiration

Mitochondria

Glycolysis Glycolysis - process where 1 molecule of glucose is broken in half, producing two molecules of (3 Carbon compound). 3 carbon molecules are called pyruvic acid.

Glucose + 2ATP 2Pyruvic Acids + 4ATP

(net= 2ATP)

Cellular Respiration

Occurs in 3 major steps: 1. Glycolysis (cytoplasm) both

aerobic and anaerobic 2. Kreb’s Cycle 3. Electron Transport Chain

(mitochondria) only in aerobic

111111 1 2

3

Flowchart Section 9-2

Glucose (C6H1206)

+ Oxygen

(02)

Glycolysis Krebs Cycle

Electron Transport

Chain

Carbon Dioxide (CO2)

+ Water (H2O)

Go to Section:

Cellular Respiration

32

http://www.chesterfield.k12.sc.us/Cheraw%20Intermediate/DaveEvans/BiologyICP/BiologyICP.html

Animations by McGraw Hill http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__how_glycolysis_works.html (Glycolysis) http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__how_the_krebs_cycle_works__quiz_1_.html (Krebs Cycle) http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__electron_transport_system_and_formation_of_atp__quiz_2_.html (Electron transport Chain) http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter25/animation__how_the_nad__works.html (How NAD Works)

http://highered.mcgraw-hill.com/sites/0072919345/student_view0/chapter8/elearning.html# (Quiz)

Teacher’s Domain http://www.teachersdomain.org/ (Muscles and Mitochondria then click the powerhouse of the cell for Quicktime video)

Equation for Glycolysis

Glucose + 2 ATP 2 Pyruvic Acids

+ 4ATP

(net= 2ATP)

What is the net energy at the end of glycolysis?

(net= 2ATP)

What must glucose be converted into before it enters

the Kreb cycle?

2 pyruvic acids

Products for glycolysis? 2 pyruvic acids, 2 ATP

Explain the Krebs Cycle (stage 2)

What happens! (3C) is broken down. 1C into CO2 and ATP,

the other 2 form Citric Acid. High energy electrons passed to the

Electron Transport chain on NAD+ and FAD

4 32 + C02

+ H20 2

Net 2 Total 36 ATP

State the 2 Carrier Molecules that leave the Kreb Cycle to enter 3rd step.

NADH and FADH2

The Role (function) of NAD+ & FAD

Electron Carriers

Products of the Kreb Cycle

2 ATP, CO2, Electrons carried on NAD+ and

FADH

Explain the Electron Transport Chain

The electron transport chain uses the energy from the Krebs cycle to make many ATP (32). High energy electrons are carried by carrier molecules called NADH. Releases H2O

How is ATP made?

ADP is adenosine di phosphate = two phosphates. During cellular respiration .... It

binds a high energy phosphate group becomes adenosine tri phosphate.

Thus ADP binds a phosphate group and makes ATP.

Draw the ATP/ADP Cycle

Products of the ETC H2O, 32 ATP

4 32 + C02

+ H20 2

Net 2 Total 36 ATP

Cellular Respiration:

• An analogy can be drawn between the process of cellular respiration in our cells and a car.

• The mitochondria are the

engines of our cells where sugar is burned for fuel and the exhaust is CO2 and H2O.

• Note that in a car that burned fuel perfectly, the only exhaust should theoretically be CO2 and H2O also.

4 32 + C02

+ H20 2

Net 2 Total 36 ATP

The process that takes place in the Mitochondria

Krebs Cycle & Electron Transport Chain

The total ATP made at the End of this process

34 ATP from Krebs Cycle & ETC 2 ATP from Glycolysis

Total=36 ATP from 1 Glucose

Section review 9-1 Questions 1,2,4. Reviewing key skills (labeling diagrams)

Section 2

What 2 environments does glycolysis take place it?

Aerobic & Anaerobic

Explain Fermentation Fermentation- releases energy (ATP) from food molecules in the absence of oxygen.

Type of respiration for fermentation

Anaerobic Occurs after glycolysis when oxygen is not present.

What is the first step in fermentation?

Glycolysis

Location for this first step Cytoplasm

Product(s) of the first step 2 pyruvic acid + 2 ATP

2 types of Fermentation 1. Lactic Acid fermentation

2. Alcoholic fermentation

2 types of Fermentation 1. Lactic Acid fermentation 2. Alcoholic fermentation

Equation for Alcoholic Fermentation

C6H12O6 -- pyruvic acid--Ethyl alcohol + CO2 + 2 ATP

Products for Alcoholic Fermentation

1. Ethyl alcohol 2. CO2 3. 2 ATP

Equation for Lactic Acid Fermentation

C6H12O6 -pyruvic acid-Lactic Acid + 2 ATP

Products of Lactic Acid Fermentation

1.Lactic Acid 2. 2 ATP

Examples of Alcoholic Fermentation

Examples: 1) Bread (Yeast) 2) Beer, Wine (Yeast)

Alcoholic Fermentation In Foods

Yeast breaks down large starch molecules into simpler sugars. CO2 & alcohol are released as air bubbles in the dough. CO2 given off causes the bread

to rise Alcohol evaporates & gives

the wonderful smell of bread baking.

http://www.taunton.com/finecooking/articles/yeast-role-bread-baking.aspx

Example of Lactic Acid Fermentation

Examples:

1) Muscle fatigue (ache) 2) Yogurt, cheeses, & milk products

(Bacteria)

Lactic Acid In Fermented Milk Products

= +

Other products:

Cheeses

Buttermilk

Sour cream

Lactobacillus

Lactic Acid Fermentation In Muscle Cells

Build up of lactic acid occurs because NADH can not release the H+ H+ builds up in muscle cells and become acidic (drops from 7.1 to 6.5). A low ph stimulates the nerve endings in the muscle resulting in the perception of pain (the burn).

http://www.brianmac.co.uk/lactic.htm

How do muscle cells make small amounts of ATP?

Body cells produce small amounts of ATP by lactic acid fermentation.

THE END