Paul Andersen introduces the concept of bioenergetics. He explains how living organisms utilize free energy in the Universe. He begins with a brief discussion of thermodynamics and Gibbs free energy. He then explains how reactions can be exergonic or endergonic. He also introduces the concepts of photosynthesis and cellular respiration.
Paul Andersen explains the process of photosynthesis by which plants and algae can convert carbon dioxide into useable sugar. He begins with a brief description of the chloroplast. He describes the major pigments in a plant (like chlorophyll a and b). He then describes both the light reaction and the Calvin cycle. He finishes with a discussion of photorespiration and strategies for avoiding this problem evolved in CAM and C4 plants.
Paul Andersen covers the processes of aerobic and anaerobic cellular respiration. He starts with a brief description of the two processes. He then describes the important parts of the mitochondria. He explains how energy is transferred to ATP through the processes of glycolysis, the Kreb cycle and the Electron Transport Chain. He also explains how organisms use both lactic acid and alcoholic fermentation.
Paul Andersen explains how a respirometer can be used to measure the respiration rate in peas, germinating peas and the worm. KOH is used to solidify CO2 produced by a respiring organism.
Paul Andersen explains how pigments can be separated using chromatography. He shows how you can calculate the Rf value for each pigment. He then explains how you can measure the rate of photosynthesis using leaf chads and water containing baking soda.
Mr. Andersen shows you how to sink leaf chads in preparation for the AP Biology photosynthesis lab. An empty syringe is used to remove gas from the leaves before the lab. As the chloroplasts absorb light they produce oxygen bubbles which eventually cause the leaves to float.
Mr. Andersen walks you through the cellular respiration lab.
Paul Andersen details the processes of photosynthesis and respiration in this video on free energy capture and storage. Autotrophs use the light reactions and the Calvin cycle to convert energy from the Sun into sugars. Autotrophs and heterotrophs use cellular respiration to convert this sugar into ATP. Both chemosynthesis and fermentation are discussed. The evolution of photosynthesis is also discussed.
Paul Andersen describes how free energy is used by organisms to grow, maintain order, and reproduce. A brief discussion of the first and second law of thermodynamics is also included. Disruptions in the amount of free energy can cause death and disruptions to popultaions, communities, and ecosystems.
Paul Andersen attempts to explain Gibbs Free Energy. He begins by using three spontaneous reactions to explain how a change in enthalpy, entropy and temperature can affect the free energy of a system. He then applies this concept to cellular respiration and photosynthesis.
