Unit 3: Dissolved Oxygen
Water’s the Matter
Pre-test
Teachers Edition
1.
Which of the following is true concerning dissolved oxygen and fish? (Objective
3; correct – C)
A.
B.
C.
D.
E.
2.
The amount of oxygen dissolved in water is
(Objective 2; correct – B)
A.
B.
C.
D.
E.
3.
the temperature of the water.
directly related to
inversely related to
exactly the same as
not influenced by
parallel to
What percentage of the atmosphere is oxygen? (Objective 1; correct – B)
A.
B.
C.
D.
E.
4.
Fish do not use oxygen so the amount of oxygen dissolved in water does
not matter.
Fish remove oxygen from the atmosphere by coming to the surface and
swallowing bubbles.
Fish remove oxygen from the water by using their gills.
The scales of fish have a vast blood supply and they remove oxygen
dissolved in the water.
Fish can breathe with lungs when they need to.
9%
21%
50%
79%
100%
When oxygen moves with respect to water, it mainly moves:
. (Objective 1; correct – A)
A.
B.
C.
D.
E.
by diffusion from the air to the water, as air has a higher concentration of
oxygen.
from the water to the air as large amounts of oxygen are produced by
aquatic plants.
from air to water, as aquatic plants pull the oxygen from the air.
from the water to the air, as the temperature of water is more stable than
the temperature of air.
from the water to the air, as water is more turbulent than the air.
5.
You measure and determine the average amount of dissolved oxygen in five
bodies of water over a year. Which one of the following would have the highest
average dissolved oxygen? (Objective 2; correct – B)
A.
B.
C.
D.
E.
6.
You are investigating the die-off of numerous fish in a river that passes near a
fertilizer plant. You are concerned that the plant may be dumping nitrates into the
river. If you wanted to measure dissolved oxygen in the river when it was at its
lowest, what time of day would be best to sample the water? (Objective 2; correct
– A)
A.
B.
C.
D.
E.
7.
5:00 a.m.
10:00 a.m.
2:00 p.m.
5:00 p.m.
10:00 p.m.
Which of the following does not increase the amount of dissolved oxygen in
water? (Objective 2; correct – B)
A.
B.
C.
D.
E.
8.
a mountain lake with numerous, aquatic plants
a rapid flowing stream at the base of a mountain
a slow moving river in West Texas
a stagnant pond in East Texas
an underground river (aquifer)
diffusion from the atmosphere
bacteria in the water
plants in the water
rapid movement of water over rocks
algae in the water
The amount of oxygen dissolved in water is measured as
same thing as
. (Objective 1; correct – B)
A.
B.
C.
D.
E.
mg/L; parts per billion
mg/L; parts per million
ounces/quart; parts per thousand
ounces/gallon; parts per million
mg/L; parts per thousand
and is the
9.
As the altitude increases, assuming constant water temperature, the amount of
oxygen dissolved in water
. (Objective 1; correct – E)
A.
B.
C.
D.
E.
10.
Dams can affect the amount of oxygen dissolved in water by all but which of the
following ways? (Objective 2; correct – D)
A.
B.
C.
D.
11.
slowing the flow of water
decreasing aeration of water
increasing the temperature of water
increasing the amount of bacteria in water
One problem that occurs when raw sewage enters rivers and streams is:
(Objective 3; correct – A)
A.
B.
C.
D.
E.
12.
stays the same
becomes unstable
increases, then stabilizes
increases
decreases
the bacteria present consume large amounts of dissolved oxygen.
the bacteria present produce toxins that can kill fish.
the bacteria present produce toxins that can kill aquatic plants.
the sewage acts as fertilizer and causes plants to grow too fast.
chemicals used to treat raw sewage will kill both fish and aquatic plants.
You are serving as a research scientist with the Environmental Protection Agency.
You are monitoring the dissolved oxygen of rivers in an area. You record the
amount of oxygen dissolved in the Apple River near the Apple Sewage Treatment
Plant to average 7 mg/dL. The amount of oxygen dissolved of the Big River near
the Big River Golf Course averages 6.5 mg/dL. Additionally, measurements of
dissolved oxygen from the Chattanooga River average 8.5 mg /dL near the
Chattanooga Dam and Electric Plant. The Durham River has an average
dissolved oxygen of 4 mg/dL near the Durham Fertilizer Plant, and the East
River, near the East River Sawmill has an average dissolved oxygen of 8 mg/dL.
Of the five riverside industries, which is most likely ignoring guidelines on
maintaining water quality? (Objective 3; correct – D)
A.
B.
C.
D.
E.
The Apple Sewage Treatment Plant
The Big River Golf Course
The Chattanooga Dam and Electric Plant
The Durham Fertilizer Plant
The East River Sawmill