Biology Past Paper PDF

made by Echo https://t.me/xb5bot Page (50) When there is not enough oxygen to perform cellular respiration, some cells will rely on glycolysis for ATP, and recycle NAD via fermentation. Many types of ferm entation in biological organisms, 2 examples: - Ethanol Fermentation: bacteria, fungi. y...

made by Echo https://t.me/xb5bot Page (50) When there is not enough oxygen to perform cellular respiration, some cells will rely on glycolysis for ATP, and recycle NAD via fermentation. Many types of ferm entation in biological organisms, 2 examples: - Ethanol Fermentation: bacteria, fungi. yeast - Lactic Acid Fermentation: muscle cells when oxygen ‫ وإﻋﺎدة ﺗﺪوﻳﺮ‬، ATP ‫ﺮ ل‬‫ ﺗﺤﻠﻞ اﻟﺴ‬‫ ﺳﺘﻌﺘﻤﺪ ﺑﻌﺾ اﻟﺨﻼﻳﺎ ﻋﻠ‬، ‫ ﻣﻦ اﻷﻛﺴﺠﻴﻦ ﻷداء اﻟﺘﻨﻔﺲ اﻟﺨﻠﻮي‬‫ﻔ‬‫ﻮن ﻫﻨﺎك ﻣﺎ ﻳ‬‫ﻋﻨﺪﻣﺎ ﻻ ﻳ‬.‫ اﻟﻔﻄﺮﻳﺎت‬، ‫ﺘﻴﺮﻳﺎ‬‫ اﻟﺒ‬:‫ ‐ ﺗﺨﻤﻴﺮ اﻹﻳﺜﺎﻧﻮل‬:‫ أﻣﺜﻠﺔ‬2 ، ‫ﺎﺋﻨﺎت اﻟﺒﻴﻮﻟﻮﺟﻴﺔ‬‫ اﻟ‬‫ أﻧﻮاع ﻛﺜﻴﺮة ﻣﻦ اﻟﻔﻴﺮﻣﺎ ﻓ‬.‫ ﻋﻦ ﻃﺮﻳﻖ اﻟﺘﺨﻤﻴﺮ‬NAD ‫ ﺧﻼﻳﺎ اﻟﻌﻀﻼت ﻋﻨﺪ اﻷﻛﺴﺠﻴﻦ‬:‫ﺧﻤﻴﺮة ‐ ﺗﺨﻤﻴﺮ ﺣﻤﺾ اﻟﻠﺒﻨﻴﻚ‬ is low, for example :- pyruvate accepts the H+ from NADH. producing NAD, lactic acid, CO2 Produces 2 ATP per glucose (less e fficient) When oxygen becomes available again lactic acid is oxidized back to pyruvic acid and enters the Krebs cycle. ATP 2 ‫ﺮﺑﻮن ﻳﻨﺘﺞ‬‫ أﻛﺴﻴﺪ اﻟ‬‫ ﺛﺎﻧ‬، ‫ ﺣﻤﺾ اﻟﻠﺒﻨﻴﻚ‬، NAD ‫ إﻧﺘﺎج‬.NADH ‫ ﻣﻦ‬+H ‫ ﻳﻘﺒﻞ‬Pyruvate -:‫ ﺳﺒﻴﻞ اﻟﻤﺜﺎل‬‫ ﻋﻠ‬، ‫ﻣﻨﺨﻔﺾ‬ ‫ ﺣﻤﺾ اﻟﺒﻴﺮوﻓﻴﻚ وﻳﺪﺧﻞ‬‫ ﻳﺘﻢ ﺗﺄﻛﺴﺪ ﺣﻤﺾ اﻟﻠﺒﻨﻴﻚ إﻟ‬، ‫ﺎ ﻣﺮة أﺧﺮى‬‫( ﻋﻨﺪﻣﺎ ﻳﺼﺒﺢ اﻷﻛﺴﺠﻴﻦ ﻣﺘﺎﺣ‬e fficient ‫ﻞ اﻟﺠﻠﻮﻛﻮز )أﻗﻞ‬‫ﻟ‬.‫دورة ﻛﺮﻳﺒﺲ‬ The Cori cycle. During exercise, muscle glycogen serves as a source of glucose 6 -phosphate for the lactate pathway (steps 1 through 3). This lactate is carried by the blood (step 4) to the liver, where it is converted back to glucose 6 -phosphate (steps 5 and 6). This is next converted into.(3 ‫ إﻟ‬1 ‫ ‐ﻓﻮﺳﻔﺎت ﻣﺴﺎر اﻟﻼﻛﺘﺎت )اﻟﺨﻄﻮات ﻣﻦ‬6 ‫ﻮﺟﻴﻦ اﻟﻌﻀﻼت ﻛﻤﺼﺪر ﻟﻠﺠﻠﻮﻛﻮز‬‫ ﻳﻌﻤﻞ ﺟﻠﻴ‬، ‫ أﺛﻨﺎء اﻟﺘﻤﺮﻳﻦ‬.‫دورة ﻛﻮري‬ ‫ ﻳﺘﻢ ﺗﺤﻮﻳﻞ‬.(6 ‫ و‬5 ‫ ‐ﻓﻮﺳﻔﺎت )اﻟﺨﻄﻮات‬6 ‫ اﻟﺠﻠﻮﻛﻮز‬‫ ﺣﻴﺚ ﻳﺘﻢ ﺗﺤﻮﻳﻠﻬﺎ إﻟ‬، ‫ﺒﺪ‬‫ اﻟ‬‫( إﻟ‬4 ‫ﻳﺘﻢ ﺣﻤﻞ ﻫﺬا اﻟﻼﻛﺘﺎت ﺑﺎﻟﺪم )اﻟﺨﻄﻮة‬ ‫ إﻟ‬‫ﻫﺬا اﻟﺘﺎﻟ‬ Page (50)  made by Echo https://t.me/xb5bot Page (51) free glucose (step 7), which can be carried by the blood (step 8) back to the skeletal muscles. During rest, this glucose can be used to restore muscl e glycogen (step 9). ، ‫ أﺛﻨﺎء اﻟﺮاﺣﺔ‬.‫ﻞ اﻟﻌﻈﻤ‬‫ ﻋﻀﻼت اﻟﻬﻴ‬‫( اﻟﻌﻮدة إﻟ‬8 ‫ﻦ ﺣﻤﻠﻬﺎ ﺑﻮاﺳﻄﺔ اﻟﺪم )اﻟﺨﻄﻮة‬‫ ﻳﻤ‬‫ واﻟﺘ‬، (7 ‫اﻟﺠﻠﻮﻛﻮز اﻟﺤﺮة )اﻟﺨﻄﻮة‬.(9 ‫ )اﻟﺨﻄﻮة‬muscl e glycogen ‫ﻦ اﺳﺘﺨﺪام ﻫﺬا اﻟﺠﻠﻮﻛﻮز ﻻﺳﺘﻌﺎدة‬‫ﻳﻤ‬ Page (51)