Cellular+Energetics

__Molecules and Cells/ Cellular Energetics__ Lab #5 - Cell RespirationWhat are respiration, dormancy, and germination? How does the rate of cellular respiration relate to the amount of activity in the cell? __Summary:__ Cells that are actively dividing (germinating) have a higher rate of cellular respiration than dormant cells. An organism's metabolism transforms matter and energy, subject to the laws of thermodynamics.

change in free energy= change in heat - (temperature in Kelvins)(change in spontaneity)

path of carbon: glucose (glyolysis outside of the mitochondria) --> pyruvate --> acetyl coA --> oxaloacetate --> CO2 molecules leave reaction in citric acid cycle --> electron transport chain (gains electrons from electron carriers NADP and FADH2) --> forms water and 34 ATP molecules
 * Summary of cellular respiration**

A six carbon glucose molecule is brought into the mitochondria where it then goes through glycolysis. Glycolysis breaks the glucose molecule into two pyruvates. This process uses 2 ATP and 2 NADHs.

__ Vocabulary words and definitions __ Glycolosis: · Process that breaks down sugars to release energy · C-H bonds are broken and energy is released · Occurs in the cytoplasm · Transforms glucose into pyruvate in order to go into the Kreb’s Cycle or produce 2 ATP o If oxygen is present then the pyruvate moves into the mitochondria for cellular respiration o If oxygen is absent, the pyruvate goes through fermentation in the cytoplasm · Produces 2 ATP Fermentation: · Regenerates NAD+ · Deriving energy from the oxidation of organic compounds · Heterotrophs use this process to convert sugars into ATP · Lactate fermentation o Occurs in humans when muscles don’t get enough oxygen · Alcohol fermentation o Bacteria and fungi o Used to make bread rise and alcoholic beverages Cellular Respiration: · Glycolosis, Krebs Cycle (Citric Acid Cycle) · Reactants: glucose and oxygen · Products: Water, Carbon Dioxide and ATP · Occurs in the mitochondria and cytoplasm · Used to create energy in the form of ATP · Released energy from sugar molecules · Occurs in all living cells Photosynthesis: · Converts light energy into usable energy so that photosynthesis produces ATP · Reactants: Co2 and H2O · Products: O2 and sugar · Occurs in the chloroplast (thylakoid and stroma) · Occurs only in autotrophic cells Kreb’s Cycle: · Breaks Acetyl Coenzyme A down into carbon dioxide and transfers released energy into electron carriers o NADH and FADH2 are the carriers · Breaks down bonds in order to release electrons and energy · Occurs in the mitochondrial matrix · Produces 2 ATP Calvin Cycle/Dark reaction: · Occurs in the stroma of chloroplasts · Uses the energy from electron carriers to produce organic compounds from carbon dioxide and water Electron Transport Chain: · Passes electrons from electron carriers to oxygen, using released energy to make ATP · Occurs in the inner mitochondrial membrane Oxidative Phosphorylation: · Process that synthesizes ATP from ADP Pyruvate: · Formed when sugar is broken down for energy in the presence of oxygen Chemiosmosis: · Diffusion of ions across a selectively-permeable membrane

__People and their experiments__

**Hans Krebs: He was a German physician and biochemist who identified the Urea Cycle and the Krebs Cycle. He discovered that metabolic chemical reactions produces energy in cells and this won him the Nobel Prize in 1953, which he shared with Fritz Lipmann. His father was an ear, nose and throat surgeon and this inspired him to study science and medicine. He earned his Ph.D. at the University of Hamburg in 1925 and then studied chemistry in Berlin for one year. Krebs identified the Krebs Cycle in 1937 at the University of Sheffield. **   ** Melvin Calvin: ** He was an American chemist who discovered the Calvin Cycle and won the Nobel Prize in Chemistry in 1961. He was born in Minnesota and shortly moved to Detroit as a young child. He attended and graduated from Central High School in 1928. He earned in Bachelor of Science in 1931 and his Ph.D. in chemistry in 1935. After these accomplishments, he spent four years doing postdoctoral work and then created a family by marrying and having three children. Eventually, Calvin and his team mapped the complete route that carbon travels through a plant during photosynthesis starting from its absorbtion as atmospheric CO2 to its conversion to carbohydrates and organic compounds. He spent his final years studying oil-producing plants as renewable sources of energy and testing the chemical evolution of life…which he wrote a book on that was published in 1969. 