Electrons flow throughout the electron transport chain via redox reactions. They flow from the most negative voltage to the most positive voltage within the chain. Thus the correct flow would be from C (most negative) to B (Less negative) to A (most positive).

Photosystems I and II are each capable of conducting electrons, with photosystem II handing off electrons to photosystem I. This is accomplished by the electron carrier molecule plastocyanin.

Photosystems I and II are responsible for the light-dependent reactions of photosynthesis. These two photosystems work in tandem to create ATP and NADPH products. ATP is created in photosystem II, while NADPH is created in photosystem I.

Excitation of photosystem II splits water in the thylakoid space into hydrogen and oxygen. The hydrogen then passes through ATP synthase to move down its concentration gradient and into the stroma. Excitation of photosystem I passes electrons to NADP⁺reductase to convert NADP⁺to NADPH. Regeneration of NADPH is necessary for the Calvin cycle.

Electrons excited in photosystem I are accepted by, thus convertingto.is the reduced form ofand whileacts as an electron acceptor in certain reactions, the light reactions utilizewhich has an extra phosphate.andare not used to accept electrons in this context.

In order to keep the Calvin cycle going, the 5-carbon molecule that carbon dioxide attaches to in the first step must be remade at the end of the cycle. This molecule is called ribulose-1,5-bisphosphate, or RuBP.

C3 plants use rubisco to fix carbon dioxide; however, oxygen also competes for binding. C4 plants have evolved to use PEP carboxylase, which only binds carbon dioxide, eliminating competition with oxygen. Furthermore, C4 plants separate carbon fixation and the Calvin cycle by location, but C3 plants do not. The light reactions of C3 and C4 plants are very similar, but C4 plants are more suited for arid climates due to their ability to close their stroma for longer periods of time to prevent water loss.

The purpose of the Calvin cycle is thefixationof carbon dioxide, which essentially turns inorganic carbon dioxide into an organic compound that can be used for energy production.C3plants only use the Calvin cycle, whereas C4 plants can use a number of processes to fix carbon, including the use of phosphoenolpyruvate carboxylase (PEP carboxylase).

ABCD correlates to anabolism=build catabolism=destroy. Anabolism is the constructive phase of metabolism during which tissues are built. Catabolism is the opposite of anabolism, representing the destructive phase of metabolism. Metabolism is the total of all the chemical changes that take place in the body.

STEVE is the pathway of sperm through the male reproductive system: Seminiferous Tubules, Epididymis, Vas Deferens, Ejaculatory duct. PAD is the layers of the meninges: Piamater, Arachnoid mater, Dura mater. RICE refers to the treatment for an injury to a joint: Rest, Ice, Compression, Elevation. AWSOME is the signs and symptoms of depression: Affect flat, Weight change, Energy loss, Sad feelings, Others (guilt, loss of pleasure, hopelessness), Memory loss, Emotional blunting.

Phosphorylases are enzymes that attach phosphate groups to acceptors by breaking a chemical bond. Phosphatases are enzymes thatremovephosphate groups.

Glycogen catabolism occurs by activation of glycogen phosphorylase, which then catalyzes the reaction of glycogen into glucose-1-phosphate (and a glycogen chain that is one glucose shorter).