Which of the following does not alter an enzymes structures

How does buring fossil fuels impact does carbon cycle? what large impact does this have on the envirnment?

What can be said about farmers in highly developed countries? a) they have little or no negative impact on the environment. b) they practice subsistence agriculture. c) they are able to incorporate polyculture into their farming practices. d) they utilize organic farming techniques on a regular basis. e) they rely on large amounts of energy from fossil fuels.

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal response by in order to it's core temperature.