the actual synthesis of atp by electron transport chain is caused by what?

Answer 1

*edited*
Hmm i'm not sure what you are asking exactly, so I'll break it down to 2 parts. There is no simple answer to this question because SO MANY THINGS ARE HAPPENING!

Basically, the entire process is known as oxidative phosphorylation.
1. The electron transport chain (ETC) consists of a series of electron carriers located on the inner mitochondrial membrane. The electron carriers (protein in nature with prostetic groups) are of progressively lower energy levels. Electrons are transferred from NADH or FADH2 to O2 by a series of redox reactions. So each time the electron is passed down to an electron carrier of a lower energy level, the difference in energy at certain stages release electrons, which is used to actively transport H+ from the matrix of mitochondrion into the intermembrane space.
The subsequent explanation of how ATP is synthesised can be described by the Chemiosmotic hypothesis (also known as Mitchell's Hypo)

2. Electrons released from the ETC is used to actively transport H+ from the matrix of mitochondrion into the intermembrane space. This creates a proton gradient, which will be the source of potential energy for ATP production.
Diffision of H+ from the intermembrane space to the matrix of the mitochondrion through the Fo protein in stalked particles.
This is what happens:
A cyclindrical rotor withiin the membrane spins clockwise when H+ flows through. A rod (or stalk) connecting the rotor and knob also spins, activating catalytic sites on the knob. A protruding knob contains catalytic sites that join inorganic phosphate to ATP to form ATP.
It's difficult to picture ALL of this without a diagram, so I added a link for you. Maybe just run through the animations if you think the level of explanation far exceeds what you are looking for...

Answer 2

The elctron transport chain is when electron carriers, usually Fe3+ are reduced to Fe2+ and the electron is then passed onto the neighbouring Fe3+ as it is attracted by the +ve charge. When this happens evergy is released and a 'random' ADP and a 'random' P join together as a result...this is known as phosphorilation. ADP + P ---> ATP (At the end of the chain the O2 acts as the terminal acceptor of electrons and H+ ions but ya dnt need to know that for this Q)

Answer 3

b. NADH > electron delivery > proton gradient > chemo-osmosis NADH transports electrons to the electron delivery chain which makes use of the skill from the electrons to pump H+ to the inter mem. area adversarial to the [] gradient. Then H+ flows down the [] gradient by ability of the multicomplex protein ATPsynthase with is part of chemiosmosis, for this reason synthesizing ATP.