Objectives:At the end of the discussion, the students are expected to:•Discuss the overall mechanism of cellular respiration•Differentiate aerobic and anaerobic respiration•Write the overall equation of cellular respiration and•Give the importance of studying cellular respiration

Cellular Respiration

Mitochondria a membrane bound cellular

structure and is found in most of the eukaryotic cells.

ranges from 0.5 to 1.0 micrometer in diameter.

power plants of the cells. plays an important role in the

production of ATP via the process of oxidative phosphorylation.

Cellular Respiration

rod shaped structure found in both animal and plant cells.

a double membrane bound organelle.

It has the outer membrane and the inner membrane.

The membranes are made up of phospholipids and proteins.

Structure of Mitochondria

Components of MitochondriaOuter membrane

It is smooth and is composed of equal amounts of phospholipids and proteins.

It has a large number of special proteins known as the porins

The outer membrane is freely permeable to nutrient molecules,ions, energy molecules like the ATP and ADP molecules. 

Inner membrane more complex in structure. It is folded into a number of

folds many times and is known as the cristae. 

is strictly permeable, it is permeable only to oxygen, ATP and it also helps in regulating transfer of metabolites across the membrane.

Components of Mitochondria

Intermembrane space space between the

outer and inner membrane of the mitochondria,

it has the same composition as that of the cell's cytoplasm.

Components of Mitochondria

Matrix is a complex mixture of

proteins and enzymes. These enzymes are

important for the synthesis of ATP molecules, mitochondrial ribosomes, tRNAs and mitochondrial DNA.

Components of Mitochondria

Cellular Respiration

the process by which the organisms obtain

the energy available in the carbohydrates

•ATP –used as cellular energy currency

Two types of Cellular Respiration:

•Aerobic Respiration: a type of respiration which is carried on in the presence of oxygen by which the oxygen is obtained from air or from water in which is dissolved.•Glucose + Oxygen Carbon dioxide + Water + Energy

Two types of Cellular Respiration:

Anaerobic Respiration – a type of respiration in which a number of one- celled organisms, including yeast and many forms of bacteria, can carry on in the absence of oxygenGlucose Lactic acid + Energy

Aerobic Respiration

Cellular Respiration

Glycolysis (Glucose Splitting Reaction)

It is the process in which one molecule of glucose is broken down to form two molecules of pyruvic acid

Occurs in the cytoplasm of the cell

4 ATP and 2 NADH are produced but this pathway produces a net gain of 2 ATP per molecule of glucose

Krebs Cycle (Citric Acid cycle)

named after Hans Kreb. occurs in the mitochondrion of a cell.

For each turn of the cycle, 3 molecules of carbon dioxide are produced from one pyruvic molecules and 5 pairs of hydrogen atoms are removed by coenzymes NAD and FAD

forms (per two molecules of pyruvic acid) carbon dioxide, two ATP molecules, 6 NADH molecules, and 2 FADH2 molecules.

Electron Transport Chain (ETC)

•This occurs in the cristae of the mitochondria where a series of cytochromes and coenzymes exist.

• The electrons in NADH and FADH2 flow through a series of electrons transport acceptors. The electron pass through a series of oxidation-reduction reaction, giving up energy to form ATP.

At the end, the electrons, hydrogen ions, and free oxygen combine to form water molecules.

Electron Transport Chain (ETC)

Chemiosmosis

• - involves the pumping of protons through special channels in the membrane of mitochondria from the inner to the outer compartments.• is the movement

of ions across a selectively permeable membrane, down their electrochemical gradient• Peter Mitchell

ANAEROBIC RESPIRATIONFermentation

• It is a process in which energy can be released from glucose even though oxygen is not available. •During this stage, the pyruvic acid produced by glycolysis

accepts 2H from NADH, and changes to some other end product. • In yeast cells, the end products are ethyl alcohol and

carbon dioxide.• In certain bacteria and in muscles, the pyruvic acid

changes to lactic acid.

Cellular Respiration

Overall Process

Overall equation during cellular respiration 

•Glucose + Oxygen CO2 + H2O + ATP

•Each ATP molecule is capable of releasing 7.3 kilocalories of energy per mole.

Sources• http://highered.mheducation.com/sites/0072507470/student_view0/chapter25/animation__electron_transport_system_and_atp_synthesis__quiz_2_.html

• http://highered.mheducation.com/sites/0072507470/student_view0/chapter25/animation__how_glycolysis_works.html

• http://highered.mheducation.com/sites/0072507470/student_view0/chapter25/animation__how_the_krebs_cycle_works__quiz_2_.html

 • https://en.wikipedia.org/ • e- BIOLOGY: The next Generation by Gil Nonato C. Santos and et.al