bioenergetics

• photosynthesis is an endothermic reaction
• At low temperatures, the rate of photosynthesis is limited by the number of molecular collisions between enzymes and substrates. At high temperatures, enzymes are denatured
• The chemical reactions that combine carbon dioxide and water to produce glucose are controlled by enzymes
• If the concentration of carbon dioxide is increased, the rate of photosynthesis will therefore increase.
• Leaves with more chlorophyll are better able to absorb the light required for photosynthesis, therefor a higher rate of photosynthesis
• higher light intensity increases rate of photosynthesis
• uses of glucose from photosynthesis- cellular respiration, to produce cellulose found in cell walls, produce amino acids for protein synthesis
• respiration is an exothermic reaction that is continuously occurring in living cells. The energy released supplies all energy needed for living processes
• respiration in cells takes place aerobically and anaerobically to transfer energy
• anaerobic respiration produces lactic acid, and is used in muscle cells
• anaerobic respiration - glucose --> lactic acid
• anaerobic respiration in plant and yeast cells glucose ---> ethanol+co2
• in anaerobic respiration, less energy is transferred than in aerobic
• if insufficient oxygen is supplied in muscle cells during exercise, anaerobic respiration will take place
• the incomplete oxidation of glucose causes a build up of lactic acid and creates an oxygen debt
• blood flowing through the muscles transports the lactic acid to the liver where it is converted back into glucose
• metabolism is the total sum of all chemical reactions in a cell or the body
• metabolism includes the conversion of glucose into starch for storage
• metabolism includes respiration
• metabolism includes the breakdown of excess proteins to form urea for excretion