PHOTOSYNTHESIS
THE CALVIN CYCLE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
concentration gradient in the stroma
|
|
|
Brownian motion of the protons.
|
|
|
peer pressure from the electrons in the stroma.
|
|
|
movement of electrons through the electron transport chain
|
Detailed explanation-1: -As the electron passes along the electron transport chain, energy from the electron fuels proton pumps in the membrane that actively move hydrogen ions against their concentration gradient from the stroma into the thylakoid space.
Detailed explanation-2: -During photosynthetic electron transport, protons accumulate at high concentration inside the thylakoid space. The concentration gradient between the inside and outside of the thylakoids is the energy source used by the ATP synthase. Protons pass through a channel of the CF0-CF1 ATP Synthase enzyme.
Detailed explanation-3: -The hydrogen ions are allowed to pass through the thylakoid membrane through an embedded protein complex called ATP synthase. This same protein generated ATP from ADP in the mitochondrion.
Detailed explanation-4: -ATP is created when hydrogen ions are pumped into the inner space (lumen) of the thylakoid. Hydrogen ions have a positive charge. Like in magnets, the same charges repel, so the hydrogen ions want to get away from each other. They escape the thylakoid through a membrane protein called ATP synthase.
Detailed explanation-5: -The ions flow through ATP synthase from the thylakoid space into the stroma in a process called chemiosmosis to form molecules of ATP, which are used for the formation of sugar molecules in the second stage of photosynthesis.