bio lab test 1
Which of the following items will you need to make a wet mount?
transfer pipette clean slide Bunsen burner timer tweezers cover slip
One inch is equal to 2.54 centimeters.
true
The formation of a green color after heating with Benedict's reagent indicates that a sample contains simple sugars.
true
When measuring the volume of water in a graduated cylinder it is important that your eye is parallel to the meniscus.
true
The liter is the metric base unit of measurement for
voulme
The negative control used in this experiment was
distilled water.
Which of the following is NOT a commonly used unit of length in the metric system?
electrometer
Which color change represents a positive reaction for the presence of starch using the iodine test?
yellow to purple
The centigram is the smallest unit of weight.
False
In the metric system, the base unit of weight is the
gram
When biuret reagent is added to a solution containing protein, the solution turns pink or purple. In the absence of protein, the solution is blue. Biuret reagent was added to solutions that may or may not contain protein. The data can be seen in the table below. What is the dependent variable in this experiment?
the color change from blue to purple
The meniscus is
the lowest margin of water level.
When testing for starch within the potato and onion, the test tube containing potato turned purple while the test tube containing onion turned orange. What can you conclude about the amount of starch in these two vegetables?
the potato contained a higher concentration of starch than the onion.
Match each reagent with the type of macromolecule that it can be used to detect 1.simple sugars. 2.protein. 3.starch.
1.Benedict's 2.biuret 3.iodine
Arrange the following steps of applying immersion oil in the correct sequence.
1.Focus on the specimen using the 40x objective lens. 2.Turn the objectives to half way between the 40x lens and the 100x lens. 3.Apply a drop of immersion oil directly onto area of the slide you were viewing. 4.Rotate the 100x lens over the microscope slide, and use the fine focus adjustment knob to sharpen the image.
Indicate the correct order of steps as you bring an object into focus under high power.
1.Place slide on stage and secure with stage clips. 2.Turn on the light and center the specimen over the light source. 3.Focus specimen on scanning objective using coarse focus adjustment 4.Rotate to low power objective, then use fine focus to sharpen the image 5.Rotate high power lens into position. 6.Readjust fine focus under high power to produce the sharpest image.
Match each test with the substance it is intended to detect. 1.lipids = 2.protein 3.simple sugars 4.starch
1.brown Paper test 2.biuret test 3.Benedict's 4.iodine
Which objective lens requires oil to be applied?
100x
The temperature outside is 40 degrees Celsius. What is this in degrees Fahrenheit?
104
The magnification of the ocular lens is
10x
What is the minimal drying time for the paper lipid test
15 min
Normal room temperature is 77 degrees Fahrenheit. What is the normal room temperature in Celsius?
25 c=(f-32)/1.8 F=(1.8*C)+32
What lens could get dirty with oil if you move the revolving nosepiece in the wrong direction after viewing under oil immersion?
40x
Please match each measurement with its equivalent answer. 1 millimeter 1000 millimeters 15 millimeters 1 centimeter 0.000515 kilometers
= 0.001 meter =1 meter =0.015 meters =0.01 meter =0.515 meters
You have successfully focused on an object with the 10x and 40x objective lenses. You have rotated the 100x objective lens into position but are unable to obtain a sharp image by rotating the fine focus adjustment knob. Which of the following is most likely to correct this problem?
Add a drop of immersion oil before rotating the 100x lens into position.
Which reagent is used to detect the presence of simple sugars?
Benedict's
Which of the following tests requires heating prior to observing results?
Benedict's test
The total magnification achieved using a 10× objective lens with a 10× eyepiece lens is 20×.
False
On the Celsius scale, water freezes at 32 degrees.
False , FP= 0 degree Celicus
During the paper test, solution 2 left a faint stain behind and was determined to be milk while solution 4 left a very definite and greasy stain behind and was determined to be oil. What can be concluded about the lipid content of milk?
It contains a lower concentration of lipids than oil.
A student is testing for the presence of protein, simple sugars, starch, and lipids using the tests summarized in the table below. The student tests an unknown solution using each of the tests and observes that the solution turns blue-black when he tests for protein. Which of the following conclusions can the student make?
No conclusion can be drawn; the student made an error.
A wet mount requires the addition of certain dyes and cell fixatives approximately 12 hours before viewing the specimen.
false
The fine adjustment knob on the microscope
fine-tunes the focus.
How is the metric system different than the standard United States system?
The metric system is based on units of 10.
What is the advantage of using a wet mount?
The motility of a specimen can be viewed under a microscope. The wet mount is a safer way to view pathogenic organisms. The specimen can be viewed as living cells. The contrast of a specimen is enhanced with the addition of water to the slide.
While testing an unknown solution a student adds Benedict's reagent and watches as the contents of the test tube turn green. The student then added amylase and heats the test tube. This causes the contents to turn red. Which of the following conclusions could the student make?
The solution has both simple sugars and starch.
The Celsius scale is primarily used in climate studies and industry.
True
When comparing the milligram, gram, microgram, and kilogram, the largest unit of weight is the kilogram.
True
When biuret reagent is added to a solution containing protein, the solution turns pink or purple. In the absence of protein, the solution is blue. Biuret reagent was added to solutions that may or may not contain protein. The data can be seen in the table below. What conclusion can be drawn from this data?
Tube D contains protein, while tubes A, B, and C do not.
In the weight exercise of the metric system lab, what object/materials did you practice weighing?
beaker and salt
Which reagent is used to detect the presence of protein?
biuret
total magnification calculations
When the scanning (4x) objective is used the total magnification will be 40x. When the low power (10x) objective is used the total magnification will be 100x. When the high power (40x) objective is used the total magnification will be 400x. When the oil immersion (100x) objective is used the total magnification will be 1000x.
Which of the following are functions of carbohydrates? (Select all that apply)
catalytic activity storage of genetic information storage of energy structural support
In the metric system, the base unit of temperature is the
celcius
The __________ causes the stage to move upward or downward.
course adjustment knob
When preparing a wet mount specimen for viewing, the specimen should be covered with
cover slip
47.0 milligrams =
all choices : 0.047 grams, 0.00047 hectograms 0.47 decigrams 4.7 centigrams
Proteins are polymers composed of
amino acids
When measuring the volume of a liquid in a graduated cylinder, at which point should the measurement be taken?
at the meniscus
The mechanical stage upper knob causes the stage to move
back and forth.
Pond water can contain many types of organisms. Which of the following are you most likely to find in a pond water sample? Please select all that apply.
bacteria algae human cells protozoa virus
Which properties of water contribute to the formation of the meniscus?
high heat of vaporization , high heat capacity,adhesion,density,univeral solvent,
When Benedict reagent is added to a solution containing simple sugars, the solution turns green, orange, or red. In the absence of simple sugars, the solution is blue. Benedict reagent was added to solutions that may or may not contain simple sugars. The data can be seen in the table below. The contents of the unknown solutions would be considered the
independent variable.
Which group of molecules are insoluble in water?
lipids
Which classes of macromolecules have a significant role in energy storage? (Select all that apply)
lipids, carbohydrates
In the metric system, the base unit of a liquid is the
liter
The coarse adjustment knob on the microscope
locates the focus plane.
A change in what component of microscopy influences the apparent size of the objects being viewed?
magnification
In the length unit exercise, what tool did you use to measure the circles?
metric ruler
Emulsifiers are
molecules with a polar end and a nonpolar end that can be used to disperse lipids into polar liquids such as water.
What does the term motile mean?
movable
An unknown liquid sample is tested for chemical composition. You receive the following results: iodine test = yellow; biuret test = blue; Benedict's test = blue; and paper lipid test = clear. Which of the following are present in this sample? (Select all that apply)
none
Which objective lens provides the highest total magnification?
oil immersion
Using oil immersion is useful because
oil immersion increases the resolving power of the specimen.
In the metric system, the ________ describes the relationship of each unit to the base unit.
prefix
n the weight exercise, the tare button was used to
reset the scale
The mechanical stage lower knob causes the stage to move
right and left
The objective lenses of the compound light microscope are attached to the
rotating nosepiece.
What instrument did you use to weigh objects in the metric system lab?
scale
Which objective lens provides the least total magnification?
scan
Which molecule is hydrolyzed (digested) by amylase?
starch
The positive control for the Iodine test was the
starch solution.
An unknown sample is tested for chemical composition. You receive the following results: iodine test = purple; biuret test = blue; Benedict's test = green; and paper lipid test = greasy spot. Which of the following are present in this sample?
starch,sugar,lipids
When converting between Fahrenheit and Celsius you should
subtract 32 and then divide by 1.8.
