Water, a natural necessity of life, is usually at a pH of 7.0. Because CO
dissolves in rain, rain is a safe pH of about 5.6, but what happens when this pH level
changes and drops to even lower acidic levels (U.S. Environmental Protection Agency)?
Near areas such as coal mining fields, highly industrious cities, highways and interstates,
rain often picks up runoff such as high metal ions from the coal, fuel and car exhaust on
the interstates, and carries the heavy metal ions away with the water. When this water
evaporates, the metal ions also evaporate with the water, later producing “acid rain.” How
does this rain affect plants, a basic need for substantial life on earth?
Scientists have performed many experiments to test the effects of acid rain and
varying pH levels on plants. Here at UGA, the four students in my lab group decided to
also scientifically discover the effects of varying pH levels when introduced to one
enzyme, amylase, which is a “crude extract from germinating barley seeds,” used to help
break down starch that is inside of the seed, providing food for the seed as it sprouts
(UGA lab book, 2-4). The lab group wanted to test how different pH levels affect the
amount of time that it takes for the enzyme, amylase, to break down the starch. Amylase
is required to break down the starch (starch hydrolysis), and the byproducts of the starch
feed the seed. The slower the break down of the starch, the longer it would take to feed
the germinating seed.
If it takes too long to feed the germinating seed, the seed may die.
According to the Worthington Biochemical Corporation, enzyme activity for