Sean-Zarina-CR+essays


 * 26. ** ** Tom notices that he is a lot more short of breath after he finishes a 200 meter sprint than when he jogs for 3 miles. ** ** He is confused because he feels as if he should feel more tired when he runs for a much longer distance. Explain to him why it makes sense that he is indeed more short of breath after running a sprint than jogging. ** ** Make sure to explain it using your scientific knowledge of cellular respiration. **

Tom is short of breath after sprinting a 200 meter dash because he is using his oxygen quicker than when he is jogging for 3 miles. When he sprints his body uses his oxygen quickly and he will feel short of breath. When he jogs he goes at a slower pace and doesn’t need as much energy as fast as he would while sprinting. While it is true that Tom will use more energy overall while jogging for 3 miles he doesn't use the energy as fast as sprinting. When Tom jogs he moves slower than when he sprints so he uses ATP and oxygen at a faster rate because he is moving faster. His body cannot get enough oxygen to replace the oxygen he is using to make ATP so he feels out of breath. While jogging he moves slowly and his body can replace the oxygen he uses to make ATP so he is not out of breath.


 * 27. **** A scientist isolates mitochondria form human cells and places them in an acid solution. The acid penetrates the intermembranous space of the mitochondria. The scientist then notices that the mitochondria start making ATP despite the fact that he is not providing any glucose for them. How is it possible that the mitochondria are still making ATP? (Think back to what an acid is, what it releases when placed in a solution and why this would make the mitochondria synthesize ATP). **

When an acid is mixed with a solution hydrogen ions are released. These hydrogen ions are actively transported into matrix by the energy lost when electrons are passed down by the ETC. This makes a high concentration of hydrogen ions in the matrix. Next the ions will diffuse back to the intermembranous space through the ATP synthase and ATP will be made, without glucose. This can only go on for so long because the ETC will run out of energized electrons.

** 28. Genetic testing reveals that baby Helen has a defective gene that results in the defective production of one of the proteins in the electron transport chain. Because of faulty instructions in her DNA, one of the proteins in her ETC is mis-shapen, and therefore it cannot perform its function as efficiently. Baby Helen is “failing to thrive” as she is having a hard time gaining weight and reaching developmental milestones. Using your knowledge of the ETC and its role in making ATP, explain why you think baby Helen is having the problems described above. **

Helen is having these problems because the proteins in the ETC are made to pass down the electrons from one to another, to make process called chemiosmosis. In chemiosmosis ATP is made, and it supplies the energy needed for the cell. The cell needs the ATP to perform its functions. Helen's proteins in the ETC cannot pass down the electrons as fast as a normal protein, causing the mitochondria to produce ATP slower. Since the cells are getting the ATP slowly in Helen's body they are failing to perform their functions as quickly as normal cells would. Therefore, Helen develops at a slower rate.


 * 29. **** Compare the basic transformation of energy during photosynthesis and cellular respiration. **

During Photosynthesis the plant changes the energy from sunlight to glucose and it uses water, carbon dioxide and sunlight to do so. In cellular respiration the mitochondria changes the energy in the glucose into ATP so it can perform its functions and to uses Oxygen do convert the glucose. In both process an electron transport chain is used and they both complete chemiosis. The processes have different steps; cellular respiration has Gylcolsis, Citric acid cycle and ETC but photosynthesis has just light-dependant reactions and the Calvin cycle. Though the processes are different they both are necessary for life on Earth.


 * 30. **** Describe the role of ATP in biochemical reactions. What is ATP used for in your cells? How do your cells get energy out of a molecule of ATP? How is ATP recharged? **

The molecule ATP supplies the energy for the biochemical reactions. Without energy the reactions could not happen. Your cells use ATP for just about any thing needing energy, such as active transport. The cells get the energy by breaking the third bond in the ATP. When broken energy is released and ATP turns into ADP. ATP is considered rechargeable because the cell just bonds another phosphate to the ADP to make the molecule ATP once again. Therefore, ATP is very important in biochemical reactions.