Ap Biology Essay on Atp

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a)The ATP molecule is composed of three components. At the centre is a sugar molecule, ribose (the same sugar that forms the basis of RNA). Attached to one side of this is a base (a group consisting of linked rings of carbon and nitrogen atoms); in this case the base is adenine. The other side of the sugar is attached to a string of three bonded phosphate groups. These phosphates are the key to the activity of ATP. Especially, the bond between the last phosphate and second to last phosphate is very unstable and when broken releases a very large amount of energy, which is essential to all life processes. b)First, chemiosmosis occurs across the inner membrane of the mitochondria which is called the cristae. Basically, H+ ions are pumped (via active transport...therefore requiring ATP) from inside the matrix of the mitochondria across the cristae, into the intermembranous space. This will create a pH/voltage/proton gradient, so then the H+ ions will move back into the matrix by going through ATP synthase proteins embedded within the cristae. Then the H+ go back in, ATP is generated. c)ATP (adenosine triphosphate) is known as the molecular currency. ATP provides energy for cells to perform functions. One type of enzyme is ATP-ase which is used in active transport. Active transport is vital in regulating concentrations in cells, that would otherwise be non-apparent due to ions/solutes diffusing down an electrochemical or concentration gradient. To go against a concentration gradient, proteins that provide this function require energy, and that energy is in the form of ATP. ATP is released during respiration, and without it, the human body would not survive. The best example of active transport is the sodium potassium pump. Sodium ions are pumped out of the cell against a concentration gradient, whilst potassium ions are pumped in. 2 potassium, enter a cell for every 3 sodium ions pumped out. This means that there is a negative net charge of the cell , as more...
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