Cairo, Egypt, in its history[?] has had a significant number of fortified gates protecting both inner and outer city. Apart from the purpose of defense they were also used for differentiation of the varied social and economic classes. Often the gates were heavily decorated as artistic pieces.
... electrons, which is then captured by a primary acceptor protein.
The chlorophyll's electron can follow either of two different pathways, cyclic or non-cyclic.
Cyclic ...