Exam 1 Short answer and essay questions (40 points).
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Your score will be added to your multiple choice exam score, for a total of 100 points.
Environmental experts have identified five underlying causes of the
environmental problems we face. What are the basic causes according to
your textbook? 2 points
ANS: According to the textbook, the basic causes of environment problems are
population growth, unsustainable resource use, poverty, not including the costs of
environment of economic goods and services in market prices, and without really
understand about the nature, we trying to manage and simplify it. Since there are five
of them, but the major problem is poverty which is seriously affect the human health
and the environment.
List 2 benefits to this planet that insects provide. 1 point
ANS: Insects play an important to pollinating flowers, without the, flowers would not
grow, and we will not have fruits and vegetables like nowadays. Also, insects eat
other insect, it is the rule of nature and it control the population of insects like pests,
so this control is very important to the earth’s natural capital.
Name five reasons microbes are said to be the real rulers of the earth. 3
ANS: First, microbes convert nitrogen gas in the atmosphere that the plants can
absorb it from the soil to get nutrients and they can stay alive. Second, if without
microbes, the soil decompose organic wastes into nutrients then will not been taking
up by plants, and we will eat them. Third, microbes can break down the waste in
water and it will be clearer for us to drink. Fourth, microbes help controlling disease
when species eat our crops. Fifth, some harmful bacteria can be prevented by some
microbes, and stop them to go into our lungs. So, microbes are the real rulers of the
earth, because they help and the environment a lot.
Define pH and the pH scale. How is the pH scale used? What is it a measure
of, exactly? 3 points
ANS: PH is the acidity or alkalinity of a solution, and pH scale is a measurement
scale to measure acidity and alkalinity of a solution which is based on the
concentrations of hydrogen ions. PH scale range is from ph 0-14, ph 0-6.9 is acidic,
and ph 7.1-14 is alkaline, if it is exactly ph7, it is neutral. The ph scale can be used to
measure how acid is it in the water and soils.