Photosynthesis and Cellular Respiration

Transcription

1 Photosynthesis and Cellular Respiration Photosynthesis a set of chemical reactions that converts carbon dioxide and water to food for plants, cyanobacteria and plant like protists Carbon Dioxide + Water + Light Energy Glucose + Oxygen

2 Cellular Respiration is a set of reactions partially occurring in the mitochondria that produces energy compounds for cells. This process occurs in ALL organisms Glucose + Oxygen Carbon Dioxide + Water + Energy

3 Plants give off oxygen as a by product of photosynthesis, and aerobic organisms use oxygen in cellular respiration. The products of one process are the raw materials of the other. Happens in Plants AND Animals Carbs and O 2 Happens in Plants MITOCHONDRIA CHLOROPLAST ATP CO 2 and H 2 O

4 Photosynthesis Occurs in the chloroplasts of green plants Chlorophyll molecules absorb light energy and begin the process

5 There are two steps involved: Step 1: The Light Dependent Reactions Photosynthesis starts with chlorophyll molecules in the thylakoid membranes It traps light and transfers its energy to ATP molecules This stage supplies the chemical energy needed to drive synthesis forward Step 2: The Light Independent Reactions (The Calvin Cycle) The reactions of photosynthesis in which carbon dioxide molecules are used to produce carbs such as glucose The energy is stored as chemical energy in the bonds of glucose

6 Cellular Respiration 1eyo The Mitochondrion The powerhouse of the cell The site of the second part of cellular respiration Location where most ATP is produced 2 Forms of Cellular Respiration: Aerobic Respiration uses oxygen, produces large amounts of ATP Anaerobic Respiration does not use oxygen, produces small amounts of ATP

7 Aerobic Cellular Respiration Occurs in 2 stages: 1) Glycolysis a series of reactions occuring in the cytoplasm that breaks a glucose molecule in into two pyruvate molecules and forms two molecules of ATP and ATP Glucose doesn't require oxygen and happens in all cells ATP

8 2) Oxidative Respiration (The Krebs Cycle) a series of reactions occurring in the mitochondrion that uses oxygen to convert pyruvate into carbon dioxide, water, and ATP 2 6 Carbon Dioxide and and 34 ATP 6 Water

9 What about prokaryotic cells??? no mitochondria=no oxidative respiration Much less efficient at producing energy!

10 Anaerobic Cellular Respiration 2 methods: 1) Alcoholic Fermentation (Ethanol) glucose is first broken down by the reactions of glycolysis it is the conversion of pyruvate to alcohol (ethanol and CO 2 ) occurs in yeast cells products of fermentation include: breads, pastries, wine, beer, liquor, soy sauce total ATP produced = 2 (from glycolysis)

11 2) Lactic Acid Fermentation the conversion of glucose to lactic acid glucose is first broken down by glycolysis occurs in the cytoplasm of bacterial and animal cells accumulation of lactate molecules in muscle tissue causes stiffness, soreness and fatigue lactic acid must be changed back to pyruvic acid in the presence of O 2 used to make cheese and yogurt total ATP produced = 2 (from glycolysis)

12 Rigor Mortis extreme lactic acid build up death=lowered body temp glucose ferments in body tissues high levels lactic acid in tissues causes rigid muscle tissue