Why is it important to monitor and control pH and temperature when preparing culture media?

pH is critical because certain cultures will not grow in acidic or basic media. on the other hand, some cultures perfer pH extremes. most cultures will grow between pH 5.5 and 7.5. In addition, both temperature and pH can cause breakdown of media components (sugars can burn, proteins can denaure, etc.) which would render the medium useless.Why is it important to monitor and control pH and temperature when preparing culture media?
things won't grow on wrong ph and temp. here is something to think about. human body temp is 37 degree centigrade. enzymes work great. Chicken body temp is 42 degree temp. The exact same enzymes as human in the chicken won't work on 37 and it has to be 42. why?'; no one knows.