.
The ruling patriarch refused to work under the infidel's service and resigned. Georgios Skholarios, who was a famous scholar indeed (studied Tomas Aquinas alongside other stuff), and a stout opponent to unification with the Catholics, who had been imprisoned (mandatory residence) at the Pantokrator Monastery (Molla Zeyrek Câmii) by Konstantinos, was elected as Gennadios II and served for quite a long time. He was no easy going type and is knowned to resighn twice to return to office later in Mehmed's reign too. He's known to have written apollogies for Orthodox Christianity against the Catholic ways as well as Islam and debated with Muslim scholars at the presence of the Sultan.

Since the terrible Latin looting in 1204 the city had never been able to get up again. A European traveller describes its state in 1430s as isolated small towns and yorks seperated with wide watelands, agriculture here and there, lumped inside a ring of walls. It changed after 1453. Mehmed, using enforced migration, filled the city up with people, mostly Muslims but also many Greeks evacuated from neighbouring villages, a sizeable Armenian colony transferred from Brusa and a community of Karaite Jews; had the population boom in a surprisingly short period and ordered (himself and other aristocracy, the Mahmud Paşa named above being a major name) trade facilities, repaired the port to the south etc. AFAIK, in a decade or so, it was the city with the highest population in Europe again. (A couple of valuable articles is sitting next to me right now but I'm too lazy to look up. Will update with more data later. )
.