NAS 2 FINAL EXAM QUESTIONS AN
D THEIR COMPLETE SOLUTIONS
Hypothesis
A suggested explanation that might be true and is subject
to testing by further observations is a(n):
Scientific theory
A concept that is supported by experimental evidence that
explains the facts in an area of study:
A dental student wants to test if fluoride is an effective
additive against tooth decay. The student studies
tooth decay in a population of people who live in
neighborhoods supplied with fluoridated water. This
student would like to ask whether access to
fluoridated water prevents tooth decay. What would be
an effective control group to ask this question?
Individuals with access to water with no fluoride added
If you were to design a long-term research study to
determine why there are no human births in Lapland
during the months of August, September, and
October, you would need to also examine a
comparison population of humans in which births
took place every month. The primary reason for
including a comparison population within the design
of this experiment would be to:
Act as a control that would ensure that the results
obtained are due to a difference in inly one variable
,Two groups of people were tested to determine
whether garlic lowers blood cholesterol levels. One
group was given 800mg of garlic powder daily for four
months and exhibited an average 12% reduction in the
blood cholesterol. The other group was not given any
garlic and after four months averaged a 3% reduction
in cholesterol. The group that was not given the garlic
was the ___________ group.
Control
The use of controls and statistical testing are two
aspects of experimental design that help to ensure
__________.
Objective and reliable results
Which of the following would contain the greatest
amount of information that scientists consider to be
true to the best of their knowledge?
A theory
A researcher is interested in determining the average
length and weight of loblolly pine tree needles in the
southeast United States. Will the data be obtained
through observation or experimentation?
Observation
The manner in which a scientist intends to conduct an
experiment is called:
The experimental design
The expected outcome of an experiment is known as:
A prediction
If the ocular lens is 10X, what would be the total
magnification for the following objective lenses? 5X,
17X, and 35X
50, 170, and 350 respectively
, What is the function of the iris (diaphragm) of the
microscope?
Regulates the amount of light that strikes the lens and
illuminates the specimen
What is the name of the thin glass plate placed on top
of a specimen when preparing a slide?
Cover slip
The microscope that you use in a lab is a(n):
Compound Microscope
What is the name of the circle you see when you look
through the ocular lens of the microscope?
The field of view
When you switch from a low-power objective lens (for
example 4X) to a higher-power objective lens (for
example 10X), what happens to the working distance
between the lens and coverslip?
The working distance decreases
What happens to the field of view when you change
from a low-power objective lens to a higher-power
objective lens? Does it increase or decrease?
The field of view decreases
When should you use the scanning lens on the
microscope?
When you begin your observations of the material on the
slide
How should you clean the lenses of a microscope?
By using clean lens paper and wiping the lenses in a
'circular' pattern
What is the proper way to carry the microscope in
lab?
One hand under the base and one hand on the arm
D THEIR COMPLETE SOLUTIONS
Hypothesis
A suggested explanation that might be true and is subject
to testing by further observations is a(n):
Scientific theory
A concept that is supported by experimental evidence that
explains the facts in an area of study:
A dental student wants to test if fluoride is an effective
additive against tooth decay. The student studies
tooth decay in a population of people who live in
neighborhoods supplied with fluoridated water. This
student would like to ask whether access to
fluoridated water prevents tooth decay. What would be
an effective control group to ask this question?
Individuals with access to water with no fluoride added
If you were to design a long-term research study to
determine why there are no human births in Lapland
during the months of August, September, and
October, you would need to also examine a
comparison population of humans in which births
took place every month. The primary reason for
including a comparison population within the design
of this experiment would be to:
Act as a control that would ensure that the results
obtained are due to a difference in inly one variable
,Two groups of people were tested to determine
whether garlic lowers blood cholesterol levels. One
group was given 800mg of garlic powder daily for four
months and exhibited an average 12% reduction in the
blood cholesterol. The other group was not given any
garlic and after four months averaged a 3% reduction
in cholesterol. The group that was not given the garlic
was the ___________ group.
Control
The use of controls and statistical testing are two
aspects of experimental design that help to ensure
__________.
Objective and reliable results
Which of the following would contain the greatest
amount of information that scientists consider to be
true to the best of their knowledge?
A theory
A researcher is interested in determining the average
length and weight of loblolly pine tree needles in the
southeast United States. Will the data be obtained
through observation or experimentation?
Observation
The manner in which a scientist intends to conduct an
experiment is called:
The experimental design
The expected outcome of an experiment is known as:
A prediction
If the ocular lens is 10X, what would be the total
magnification for the following objective lenses? 5X,
17X, and 35X
50, 170, and 350 respectively
, What is the function of the iris (diaphragm) of the
microscope?
Regulates the amount of light that strikes the lens and
illuminates the specimen
What is the name of the thin glass plate placed on top
of a specimen when preparing a slide?
Cover slip
The microscope that you use in a lab is a(n):
Compound Microscope
What is the name of the circle you see when you look
through the ocular lens of the microscope?
The field of view
When you switch from a low-power objective lens (for
example 4X) to a higher-power objective lens (for
example 10X), what happens to the working distance
between the lens and coverslip?
The working distance decreases
What happens to the field of view when you change
from a low-power objective lens to a higher-power
objective lens? Does it increase or decrease?
The field of view decreases
When should you use the scanning lens on the
microscope?
When you begin your observations of the material on the
slide
How should you clean the lenses of a microscope?
By using clean lens paper and wiping the lenses in a
'circular' pattern
What is the proper way to carry the microscope in
lab?
One hand under the base and one hand on the arm
