RESPIRATION Unit 5 - Ecology

Cellular Respiration  A series of metabolic processes that take place within a cell in which biochemical energy is harvested from organic substance (e.g. glucose) and stored as energy carriers (ATP) for use in energy- requiring activities of the cell.

What does that mean?  We cannot use food directly as energy, we have to break the bonds within nutrients to get energy in the form of ATP.  To make ATP we take glucose from the food we eat plus oxygen we breathe in and make energy and water, plus the waste product carbon dioxide.

Where does respiration happen?  Remember the powerhouse of the cell?  mitochondria

Respiration Formula  C 6 H 12 O O 2  6 CO H 2 O + (ATP)  Glucose is the fuel for the cell, but it is not in a form that we can use, it has to be converted into ATP, the ultimate cellular energy source.  What looks familiar about this formula?  Remember, the cycle of matter!

Types of cellular respiration  Occurs in the presence of oxygen  Maximizes ATP output  Each cycle through aerobic respiration makes 36 ATP molecules.  Happens without oxygen  Minimal ATP output (since it occurs without additional oxygen)  Each cycle through anaerobic respiration makes 2 ATP molecules. AerobicAnaerobic

Anaerobic Respiration  Occurs in animals  This is what happens to your muscles after you work out too long, you build up lactic acid.  Occurs in plants and fungi  This is how bread and beer is made.  Ex. Yeast, CO 2 released causes bread to rise. Lactic Acid FermentationAlcoholic Fermentation