Cellular Respiration

 During photosynthesis the Sun’s energy is captured & stored in the form of carbohydrates & other organic molecules

What happens to this stored energy?  Most of the stored energy will be used for the life processes of the autotroph  Some will be reserved & available to heterotrophs, who in turn, use it for their own life processes  All cells break down complex organic compounds into simpler molecules  Cells use some of the energy released to produce ATP from ADP & phosphate

Respiration  All cells break down complex organic compounds into simpler molecules  Breaking down releases energy stored in the molecular bonds of the organic compounds  Some of the energy released to produce ATP from ADP & phosphate

Organic Compounds No Oxygen Fermentation (anaerobic) Oxygen Aerobic Respiration ATP Glycolysis

 1 st phase of cellular respiration  Produces ATP & other products  Little ATP formed  Other products will follow one of two additional pathways  Which path followed depends on the presence or lack of O 2

Glycolyisis – a biochemical pathway  6 carbon chain molecule broken & 2 STP molecules, through a series of steps, into 2 – 3 carbon molecules (pyruvic acid molecules) AND 4 molecules of ATP  2 ATP used & 4 made !  Happens in the cytosol

What happens to the Pyruvic Acid?  Depends on whether or not oxygen is present

Where does respiration happen?  In the cytosol if no oxygen is present

Where does respiration happen?  In the mitochondria if oxygen is present

The Outer Membrane  The outer membrane contains many complexes of integral membrane proteins that form channels through which a variety of molecules and ions move in and out of the mitochondrion.

The Inner Membrane  Forms the inner folds of the cristae

Cristae  Cristae are the finger-like projections of the inner mitochondrial membrane and they increase the surface area for the electron tranport carriers and ATP synthase which are located in the membrane.

The Matrix  The matrix contains a complex mixture of soluble enzymes that catalyze the respiration of pyruvic acid and other small organic molecules.