March 27-28, 2017 Biology, Dynamics of Life Chapter 9, pages 220-241 GlucOSE AND ENERGY March 27-28, 2017 Biology, Dynamics of Life Chapter 9, pages 220-241

ENERGY CYCLE FROM LIGHT TO ATP

REVIEW: PHOTOSYNTHESIS TO GLUCOSE

GLUCOSE TO ATP OVERVIEW

ENERGY OVERVIEW

CELLULAR RESPIRATION OVERVIEW The process by which mitochondria break down glucose to make ATP Two types Aerobic respiration: requires oxygen and carried out by plants, animals, and some bacteria Anaerobic respiration: requires no oxygen and carried out by yeast, some bacteria, and sometimes animals   Chemical equation for aerobic respiration C6H12O6 + 6O2  6CO2 + 6H2O + chemical energy (Chemical/Empirical Forms) glucose + oxygen  carbon dioxide + water + ATP (Scientific Name)

Aerobic Respiration Photorespiration Cellular Respiration The excess respiration taking place in green cells in the presence of light is called photorespiration. It is also called C2 cycle because two carbon glycolic acid acts as the substrate. Three organelles, namely chloroplast, peroxisome and mitochondria are involved in photorespiration. Generally photorespiration is found in C3 plants. It takes place in the presence of oxygen and the respiratory substrate (glucose/pyruvate) to completely oxidise to carbon dioxide and water as end products. This type of respiration is of common occurrence and it is often used as a synonym of respiration

AEROBIC RESPIRATION Aerobic respiration starts outside the mitochondria (plural of mitochondrion) Makes energy for the cell through the breakdown of organic carbon to power aerobic respiration Steps of aerobic respiration Glycolysis: First step breaks down glucose into pyruvate (Intermediate step: Change pyruvate to acetyl CoA) Citric Acid Cycle: Second step uses the acetyl CoA to make electrons for the last step Electron transport chain: Third step uses the electrons to make a lot of ATP

Glycolysis Glycolysis is a series of reactions that and extract energy from glucose by splitting it into two three-carbon molecules called pyruvates. Glycolysis is an ancient metabolic pathway, meaning that it evolved long ago, and it is found in the great majority of organisms alive today In organisms that perform cellular respiration, glycolysis is the first stage of this process. However, glycolysis doesn’t require oxygen, and many anaerobic organisms—organisms that do not use oxygen—also have this pathway.

Differences in Glycolysis

Citric Acid Cycle The citric acid cycle (CAC) – also known as the tricarboxylic acid (TCA) cycle or the Krebs cycle is a series of chemical reactions used to released stored energy from fats, carbohydrates, proteins into carbon dioxide and ATP by extracting elections and hydrogen in the mitochondria

Electron Transport Chain Is a series of reactions of protein complexes that is responsible for producing: Water (with the help of oxygen we breathe) up to 34 ATP (thanks to the proton gradient) NAD and FAD (which are recycled to be used again in the Citric acid cycle and glycolysis) Importance This process happens in the mitochondria this only happens in aerobic conditions( oxygen present). If there is a shortage of oxygen cellular respiration will take an alternative pathway at the end of glycolysis resulting in the the production of lactic acid and ATP.

Adenosine Triphosphate What is the purpose of ATP? All organisms require energy for Active transport – Against the concentration gradient, low to high concentration Cell division-spindle fibers attaching and pulling chromosomes to centrioles Movement-endocyctosis, exocytosis, muscles Production of proteins, nucleic acids, Energy is stored in the ATP molecule The energy is stored in phosphate attached to ADP (Adenosine Diphosphate) to create ATP (Adenosine Triphosphate) The released phosphate attaches to molecules and changes their structural orientation which alters their chemical affinity (reactivity) Molecules with phosphate attached are used to create subunit When the phosphate is used, it detaches and the chemical reaction is usually at the end of the Continual Cycle Cells recycle the ADP to make new ATP to store more energy for future use Many proteins have spots where ATP attaches to provide energy for the protein or molecule to do its job, then the ADP is released for recycling

carbon dioxide + water + sunlight carbon dioxide + water + ATP Energy Over View Photosynthesis Plants Only Uses sunlight to initiate making glucose Carbon dioxide diffuses in Oxygen diffuses out carbon dioxide + water + sunlight  glucose + oxygen Respiration Animals and Plants Uses or eats glucose in plants to access and breakdown glucose Oxygen diffuses or inhales in Carbon dioxide diffuses out glucose + oxygen  carbon dioxide + water + ATP       https://www.youtube.com/watch?v=dHeOyQBuH6E