B. the activity keeps blood levels of ammonia within a certain low range that the body can tolerate
Multicellular is the word you're looking for ;-)
It has been estimated that ‘slash and burn’ agriculture is
used by up to 500 million people worldwide. The term describes the practice of
cutting and/or burning of natural vegetation for conversion into agricultural
fields. Besides the disastrous implications for forest ecosystems, the practice
can impact the atmosphere in two main ways if burning is implemented. Firstly
by causing air pollution from the smoke, and secondly by increasing carbon
dioxide in the atmosphere, which is a greenhouse gas and a driver of climate
change. Living trees also remove carbon dioxide from the atmosphere during
photosynthesis, and the process of ‘slash and burn’ effectively removes their
carbon capturing contributions to ameliorating climate change.
