Electron flow/ Conventional flow Huh?

Yea conventional flow is the flow of holes or positive charge carriers, electron flow is the flow of electrons. On a fuse it doesnt matter since the current is the same in a series loop, it is kept at the positive since the entire vehicle is negative. But in reality it will not matter either way is a chassis short does not occur.

 Not sure about the flow question but it really doesnt matter what you want to think of as moving, you can say electrons move or holes move. Holes being the absence of an electron, its like leaving a parking spot and instead of saying cars are leaving, you say parking spots are forming, one is just the negative effect of the other. You can not lose electrons in a loop, so the movemement will always be equal and opposite.

The diode question is the same way, you can flood the N-side (cathode) with electrons to forward conduct or you can pull the electrons from the P-side (anode). Eitherway you will still cause the depletion layer to fill and forward conduct.

hope that helps...

Well its not that postive charges move technically, the positive charge only exists because of the loss of an electron. They are directly related, if you remove an electron you will have a positive charged area. No positive charge carrier technically moves, protons cant move only the electrons are mobile. The hole movement is just a play on words describing the electron movement.

Technically in a diode the electrons do move from the cathode to the anode (N to P), so the positive charge cariiers move in the opposite direction.

KIRCHOFFS LAW...IF I REMEMBER CORRECTLY....CHECK IT OUT...!!