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# 2c-d, Cellular respiration & cell compartmentalization and its origins

Questions on cellular respiration and the origins of cell compartmentalization.

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• If ATP=Energy, then what's ADP?
ATP stands for Adenosine triphosphate .
Loss of of an inorganic phosphate (Pi) from ATP results in ADP.
• At , can you explain how you knew that the efficiency could be calculated by energy stored in ATP over total energy from oxidation of glucose?
• When glucose is broken down, it releases 686Kcal, but ATP only stores 219Kcal, so he divides 219 by 686 to get a percentage of the energy that is actually stored in ATP. The other part of it is released by heat.
• Are students allowed to use a calculator on free response questions?
• From the College Board website:
"A four-function (with square root), scientific, or graphing calculator is permitted on both the multiple-choice and free-response sections of the AP Biology Exam since both sections contain questions that require data manipulation. Students may bring two permitted calculators to the exam. Calculators should be in good working order and may not be shared. "
So yes, don't worry, you can use a calculator.
• How I am supposed to implicitly know the equations used in 2c? Are they given? I wouldn't know them otherwise.
• what does heat have to do with atp
• Heat has nothing to do with ATP. What you are confused with is the part about the excess energy. This question is kind of a physics question but because of the Conservation of Energy the resulting energy always has to be the same. However, efficiency can never be 100%. In this case some of the excess energy is converted into thermal energy which is also known as heat.
• if ATP=Energy, then what's ADP?=low energy+size=the type of ATP it is or was
(1 vote)
• ATP stands for Adenosine TriPhosphate. This has 3 phosphate groups attached.
AMP stands for Adenosine MonoPhosphate. This has 1 phosphate group attached.
The bonds between the phosphates are where the energy is stored. ATP, with its 3 phosphate groups, is like a fully charged battery (a phosphate could be removed). ADP is like a partially charged battery (A phosphate could be added OR removed).
• it could be big atp and small atp, it dipends on what type of atp it is
(1 vote)
• ATP is Adenosine Triphosphate in which the molecule still has three phosphate groups attached to it. ADP is Adenosine Diphosphate in which the molecule now has two phosphate groups attached. The terminal phosphate bond is released which forms from the ATP, ADP, inorganic phosphate, and energy.