No student devices needed. Know more
26 questions
When heating a solution in a test tube, a student should
point the test tube in any direction
hold the test tube with two fingers
cork the test tube
wear goggles
A student designed an experiment to determine if air temperature had an effect on the rate of photosynthesis in corn plants.
The independent variable in this experiment is the
air temperature at which the corn plants were grown
amount of carbon dioxide used by the corn plants
volume of oxygen produced by the corn plants
number of corn plants used
In order to be accepted, a scientific theory must be
widely tested and supported by extensive data
based on the results of a single experiment
controversial and cause debate
in line with all previous historical ideas
A mineral supplement designed to prevent the flu was given to two groups of people during a scientific study. Dosages of the supplement were measured in milligrams per day, as shown in the table below.After 10 weeks, neither group reported a case of the flu.
Which procedure would have made the outcome of this study more valid?
test only one group with 200mg of the supplement
test the supplement on both groups for 5 weeks instead of 10 weeks
test a third group that receives 150mg of the supplement
test a third group that does not receive the supplement
Which statement best describes a scientific theory?
It is a collection of data designed to provide support for a prediction
It is an educated guess that can be tested by experimentation
It is a scientific fact that no longer requires any evidence to support it.
It is a general statement that is supported by many scientific observations
In an appropriately designed experiment, a scientist is able to test the effect of
a single variable
multiple variables
the hypothesis
scientific observations
Which statement describes the best procedure to determine if a vaccine for a disease in a certain bird species is effective?
Vaccinate 100 birds and expose all 100 to the disease.
Vaccinate 100 birds and expose only 50 of them to the disease
Vaccinate 50 birds, do not vaccinate 50 other birds, and expose all 100 to the disease
Vaccinate 50 birds, do not vaccinate 50 other birds, and expose only the vaccinated birds to the disease.
A new drug for the treatment of asthma is tested on 100 people. The people are evenly divided into two groups. One group is given the drug, and the other group is given a glucose pill. The group that is given the glucose pill serves as the
experimental group
limiting factor
control
indicator
In a scientific investigation, after the question is defined, the next step is most likely
formulating a hypothesis
identifying needed equipment
designing the experiment
collecting the data
A clear plastic ruler is placed across the middle of the field of view of a compound light microscope. A row of cells can be seen under low-power magnification (100×).
What is the average length of a single cell in micrometers (µm)?
10µm
100µm
200µm
2000µm
A transparent metric ruler is placed on the stage of a microscope and observed under low power. The diameter of the field of vision was found to be 2 millimeters. How many micrometers is the diameter?
10
200
1,000
2,000
The diagram below represents the measurement of a biological specimen.
What is the approximate length of the specimen in millimeters?
25 mm
30 mm
35 mm
40 mm
What is the approximate length of the earthworm shown in the diagram below?
9 mm
90 mm
10.6 cm
106 cm
The diagram below represents the measurements of two leaves.
The difference in length between leaves A and B is closest to
20 mm
20 cm
0.65 m
1.6 µm
How much water should be added to the graduated cylinder shown below to increase the volume to 15 milliliters?
11 mL
10 mL
3 mL
4 mL
The diagram below shows a portion of a graduated cylinder.
What is the volume of the liquid in this cylinder?
22 mL
24 mL
25 mL
26 mL
An important function of the ultracentrifuge is to
increase the magnification of different parts of cells
slice specimens embedded in wax into thin sections
transplant nuclei from one cell to another
separate different cell organelles by their density
A student is viewing a plant stem cross section using a compound light microscope.
What parts of the microscope should the student use to bring the image into focus?
A and F
B and E
C and D
D and F
While viewing a specimen under high power of a compound light microscope, a student noticed that the specimen was out of focus. Which part of the microscope should the student turn to obtain a clearer image under high power?
eyepiece
coarse adjustment
fine adjustment
nosepiece
After switching from the high-power to the low-power objective lens of a compound light microscope, the area of the low-power field will appear
larger and brighter
smaller and brighter
larger and darker
smaller and darker
A slide of human blood cells was observed in focus under the low-power objective of a compound light microscope that had clean lenses. When the microscope was switched to high power, the image was dark and fuzzy. Which parts of the microscope should be used to correct this situation?
nosepiece and coarse adjustment
diaphragm and ocular
objective and fine adjustment
diaphragm and fine adjustment
A microscope with 10× and 40× objectives is used to scan a slide to locate a specimen. The largest field of vision would be provided by using the
coarse adjustment
widest diaphragm opening
10× objective
40× objective
The structure of a cell nucleus would be seen in the greatest detail by use of
a compound light microscope
an ultracentrifuge
a dissecting microscope
an electron microscope
The diagram below represents cells seen in the low-power field of view of a compound light microscope.
The length of one of these cells is approximately
200 µm
400 µm
500 µm
2,000 µm
The diagram below represents two cells next to a metric measuring device under the low-power objective of a compound light microscope.
What is the approximate length of a nucleus of one of these cells?
100 µm
500 µm
1000 µm
1500 µm
Base your answer on The diagram below represents the field of view of a compound light microscope. Three unicellular organisms are located across the diameter of the field.
What is the approximate length of each unicellular organism?
250 µm
500 µm
1,000 µm
1,500 µm
Explore all questions with a free account