CELLULAR RESPIRATION Lesson 4.4 Overview of Cellular Respiration

CELLULAR RESPIRATION  Key Concept: The overall process of cellular respiration converts sugar into ATP using oxygen.

CELLULAR RESPIRATION CONTINUED  Cellular Respiration is an aerobic process =it needs oxygen to take place  Cellular respiration occurs in the Mitochondria.(recall they are the “powerhouses” where most energy/ATP is produced)

MITOCHONDRIA  Before ATP is produced, foods must first be broken down by glycolysis.  Glycolysis- splits glucose into 2 3-carbon molecules and makes 2 molecules of ATP.  Glycolysis is an anaerobic process-it does not need oxygen to take place.  Glycolysis occurs in the cytoplasm.  Glycolysis is necessary for cellular respiration to occur. Its products are then broken down in mitochondria to make more ATP.

FIGURE

CELLULAR RESPIRATION Stage 1: KREBS CYCLE  Occurs in matrix (interior space of mito) and makes molecules that carry energy to stage 2  Step 1 : The 3-carbon molecules from glycolysis are broken down= small ATP  CO2 is given off as waste.  Step 2 : Energy is transferred to stage 2 Stage 2: ELECTRON TRANSPORT  Takes place in inner mitochondrial membrane and uses the energy carrying molecules from KC and oxygen to make ATP  Step 3: The energy carrying molecules from glycolysis and KC enter Electron Transport Chain in inner membrane  Step 4: LARGE # of ATP molecules made.  Oxygen enters and water is made.  Water and heat are given off as waste

CELLULAR RESPIRATION EQUATION