Replaced how? If you mean like the Roman empire, that would be incorrect. Both empires considered each other Roman and both empires considered themselves Roman. So when the west fell, the Byzantines did not 'replace' the western Romans in being Roman. Instead, they just kept on being Roman as their western counterparts fell. However, for a period, the Byzantines did manage to reconquer parts of the Western Empire and even Rome, but that was relatively short-lived. In that case, you could argue that the Byzantines sort of did replace the western Romans in being the Roman empire with Rome in its possession. However, that is a stretch in my opinion.
In short: False, the Eastern Romans did not replace the western Romans as they were both seen as Romans, just with different governments.
The Christian Church was a major power in the Western Europe during the Middle Ages. The church was a powerful institution that ordered many facets of life during the Middle Ages. It gave legitimacy to political institutions and provided direction to the lives of the average people as well.
Environmental issues in Africa. Environmental issues in Africa are caused by anthropogenic effects on the African natural environment and have major impacts on humans and nearly all forms of endemic life. Issues include desertification, problems with access to safe water supply, population explosion and fauna depletion