Overview of Cellular Respiration



Overview of Respiration

- aerobic = requires oxygen to occur (ex: cellular respiration)

vs.

anaerobic = does not require oxygen to occur (ex: glycolysis and fermentation)

ATP

Oxygen Present Oxygen Absent

ATP No ATP

Glycolysis

- takes place in the cytoplasm of cells

- always occurring and does not require oxygen

- occurs before cellular respiration or fermentation

- 2 ATP are used to start process

- breaks down glucose into a net of 2 ATP, 2 pyruvate, and 2 NADH

- Why is there a net of 2 ATP?

- products (pyruvate and NADH) enter either cellular respiration or fermentation

- Efficiency = 3.5 % (only 2 ATP are made)

Overview of Cellular Respiration

= releases chemical energy from sugars and other organic compounds to make ATP when oxygen is present

- occurs in the mitochondria of cells

Cellular Respiration – 2 Stages

- occurs in the mitochondria

1) Krebs Cycle

= produces molecules that carry energy to the second stage of cellular respiration

- occurs in the matrix of the mitochondria

- pyruvate from glycolysis is broken down

- some ATP and other energy forms are made

- carbon dioxide is given off as a waste product

2) Electron Transport Chain

- occurs in the inner membrane of a mitochondria

- made of proteins

- uses energy from Krebs cycle and oxygen to make ATP

- water and heat are given off as waste products

Efficiency of Cellular Respiration = 66% (38 ATP are made)

Equation for Cellular Respiration

C6H12O6 + 6O2 (((((( 6CO2 + 6 H2O

(sugar = glucose) (oxygen) (carbon dioxide) (water)

Fermentation

- starts with glycolysis

- does not make ATP (but allows glycolysis to continue)

Types

1) Lactic Acid Fermentation

- occurs in your muscle cells

- produces lactic acid, results in muscle fatigue and cramps

- produces NAD+ that goes back to glycolysis

2) Alcoholic Fermentation

- produces alcohol (ethyl) and carbon dioxide

- produces NAD+ that goes back to glycolysis

Lactic Acid Fermentation Alcoholic Fermentation

Importance of Fermentation

- produces food products we use (bread, cheese, yogurt)

- allows glycolysis to continue

- microorganisms in digestive tract break down food (allows more nutrients to be absorbed)

-----------------------

Organic Compounds

Glycolysis

Fermentation

(anaerobic)

Cellular Respiration

(aerobic)

[pic]

[pic]

[pic]

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download