Cellular Respiration Chapter 9

Food and Calories The food and drink that you consume provide a source of energy for your cells. The energy is used to make ATP. The food and drink that you consume provide a source of energy for your cells. The energy is used to make ATP. Calorie – the amount of energy needed to raise one gram of water one degree Celsius. Calorie – the amount of energy needed to raise one gram of water one degree Celsius. Kilocalorie (on labels) – 1000 calories Kilocalorie (on labels) – 1000 calories Food also provides the building blocks for your cellular products (proteins, hormones, etc.) Food also provides the building blocks for your cellular products (proteins, hormones, etc.)

An overview of Cellular Respiration Cellular respiration can be aerobic (with oxygen), or anaerobic, (without oxygen) Cellular respiration can be aerobic (with oxygen), or anaerobic, (without oxygen) Aerobic respiration has 3 main steps: Aerobic respiration has 3 main steps: 1. Glycolysis 1. Glycolysis 2. Krebs Cycle 2. Krebs Cycle 3. Electron Transport Chain 3. Electron Transport Chain

Equation for Cellular Respiration: 6O 2 + C 6 H 12 O 6 → 6CO 2 + 6H 2 O + 36 ATP 6O 2 + C 6 H 12 O 6 → 6CO 2 + 6H 2 O + 36 ATP Oxygen and Glucose react or form carbon dioxide, water, and ATP. Oxygen and Glucose react or form carbon dioxide, water, and ATP. Other sugars, starch, fats, and proteins can also be used as energy sources. Glucose is just the simplest energy form. Other sugars, starch, fats, and proteins can also be used as energy sources. Glucose is just the simplest energy form. How does this equation relate to photosynthesis? How does this equation relate to photosynthesis?

Glycolysis – Splitting Glucose Glycolysis occurs in the cytoplasm. Glycolysis occurs in the cytoplasm. One glucose molecule into two molecules of pyruvic acid. One glucose molecule into two molecules of pyruvic acid. Uses 2 ATP but makes 4 ATP. Net 2 ATP Uses 2 ATP but makes 4 ATP. Net 2 ATP Makes 2 NADH+ Makes 2 NADH+ Does NOT use oxygen. Does NOT use oxygen.

The Krebs Cycle Occurs in the matrix of the mitochondrion. Occurs in the matrix of the mitochondrion. Pyruvic acid enters the cycle, where a series of enzyme- controlled reactions create NADH+ and FADH+ (energy carriers) Pyruvic acid enters the cycle, where a series of enzyme- controlled reactions create NADH+ and FADH+ (energy carriers) CO 2 is a waste product. CO 2 is a waste product.

The Electron Transport Chain H+ ions that were generated from the Krebs cycle build up outside of the inner mitochondrial membrane. H+ ions that were generated from the Krebs cycle build up outside of the inner mitochondrial membrane. The H+ ions are forced through ATP synthetase, creating 3 ATPs for every turn. The H+ ions are forced through ATP synthetase, creating 3 ATPs for every turn.

Electron Transport Chain… Oxygen is used as the final electron acceptor. Oxygen is used as the final electron acceptor. H+ and oxygen combine to form water, a waste product. H+ and oxygen combine to form water, a waste product. Without oxygen, the entire process backs up, and ATP cannot be created. Without oxygen, the entire process backs up, and ATP cannot be created.

Summary of Cellular Respiration Glucose is split into pyruvic acid in the cytoplasm In the mitochondria, the Krebs cycle creates CO 2 and NADH+ and FADH+ ATP synthetase creates ATP on the inner membrane of the mitochondria. Oxygen and H+ make water. A total of 36 ATPs are formed by aerobic respiration.

Anaerobic Respiration If your body uses energy very quickly, pyruvic acid can build up. If your body uses energy very quickly, pyruvic acid can build up. ATP is produced anaerobically by turning the pyruvic acid into lactic acid. ATP is produced anaerobically by turning the pyruvic acid into lactic acid. Lactic acid builds up in muscles and is painful. Lactic acid builds up in muscles and is painful. Intake of oxygen (heavy breathing) removes lactic acid from your muscles. Intake of oxygen (heavy breathing) removes lactic acid from your muscles.

Anaerobic Respiration.. Fermentation is a valuable anaerobic process used to make ATP by yeasts and bacteria. Fermentation is a valuable anaerobic process used to make ATP by yeasts and bacteria. Fermentation produces CO 2 and ethyl alcohol as by- products. Fermentation produces CO 2 and ethyl alcohol as by- products. Valuable in the food and drink industry: yogurt, beer, wine, cheese, sauerkraut… Valuable in the food and drink industry: yogurt, beer, wine, cheese, sauerkraut…