My Classroom Material 117 - BIOLOGY JUNCTION

Metric Measurement Lab

Metric Measurement Lab

Part A: Count your drops!

Take a guess – How many drops of water will it take to equal 1 milliliter? _____ drops

Follow the directions to find the number of drops in 1 milliliter of water, then answer the questions. You will need a small graduated cylinder (25 ml), a beaker of water, and an eyedropper for this section. Remember to read the bottom of the meniscus when you are reading the volume of a liquid in a graduated cylinder.

Fill a small graduated cylinder with 10 ml of water.
Count the number of drops it takes to raise the water to 11 ml. Record the number in the chart.
Leave the water in the graduated cylinder and count the number of drops it takes to raise the water to 12ml. Record the number in the chart.
Leave the water in the graduated cylinder and count the number of drops it takes to raise the water to 13ml. Record the number in the chart.
Calculate your average and round to the nearest tenth.

# of drops to 11 ml

# of drops to 12 ml

# of drops to 13 ml

Average

Based on your average, how close were you to your guess?________

Based on your average, how many drops would it take to make 1 liter? _______

Part B: Water Displacement

Follow the directions to find the volume of three marbles using water displacement.

Add 20 ml of water to a 100 ml graduated cylinder. Record this amount in the chart.
Add three marbles to the cylinder and measure the volume. Record this amount in the chart.
Find the difference between the two measurements and record in the chart. The difference between the two measurements will be the volume of the three marbles.

Volume of Water Before adding Marbles (ml)

Volume of Water After Adding Marbles (ml)

Difference in Volume (ml)

Volume of 3 Marbles

Part C: Mass Mania

The gram is the standard unit of mass in the metric or SI system. The basic instrument used to measure mass is the mass balance. Some mass measurements can be made using an electronic balance.

Check to see that the Pointer is pointing to zero.
If it is not, check to see that all the Riders (weights) are all the way to the left at the Zero mark.
Adjust the balance by turning the Adjustment Screw slowly until it points to zero.
Place your metric ruler on the pan and read & record the ruler’s mass.
After resetting the balance to Zero, measure and record the mass of the empty 50-ml graduated cylinder and then the 3 marbles.
Reset the balance to ZERO when all items have been massed.

Mass of Metric Ruler (g)

Mass of Empty 50-ml graduated cylinder (g)

Mass of 3 Marbles (g)

Part D: Volume by Formula

Use the formula to find the volume of the box. Measure to the nearest centimeter before calculating your answer. If necessary, Round your answer to Two Decimal places.

Volume = length x width x height

__________ x __________ x __________ =________________cm3

Part E: Color Challenge

1. Obtain the following items from your teacher:

3 beakers with colored water- 25 ml of each color (red, blue, and yellow)
1 graduated cylinder (25 ml – 50 ml)
1 eyedropper
6 test tubes labeled A, B, C, D, E, and F

2. Perform each step outlined below using accurate measurements.

Measure 17 ml of RED water from the beaker and pour into test tube A.
Measure 21 ml of YELLOW water from the beaker and pour into test tube C
Measure 22 ml of BLUE water from the beaker and pour into test tube E.
Measure 5 ml of water from test tube A and pour it into test tube B.
Measure 6 ml of water from test tube C and pour it into test tube D.
Measure 8 ml of water from test tube E and pour it into test tube F.
Measure 5 ml of water from test tube C and pour it into test tube B.
Measure 2 ml of water from test tube A and pour it into test tube F.
Measure 4 ml of water from test tube E and pour it into test tube D.

3. Complete the chart.

Test Tube	Color	Final Volume (ml)
A
B
C
D
E
F

Click HERE for Notebook Copy

Metric Measurement PPT Questions

Metric Measurement
ppt Questions

Metric System

1.When and by whom was the metric system developed?

2. The metric system is based on powers of ________.

3. Where is the metric system used?

4. The metric system is especially used by what group?

5. How is the metric system abbreviated & how did it get this abbreviation?

Metric Prefixes

6. Regardless of the ________, the metric system uses the __________ prefixes.

7. Give 3 of the most common metric prefixes and their value.

8. One meter equals how many centimeters? How many millimeters?

Length, Mass, and Volume

9. Define length.

10. What is the SI base unit for length?

11. _________ sticks or __________ rulers are used to determine length in the metric system.

12. Define mass.

13. If two object are the same size, will theyhave the same mass? Explain your answer.

14. What is the SI unit for mass?

15. What common object has approximately the mass of one gram?

16. How could you change the mass of an object?

17. A ___________ ___________ __________ is a scale used to measure metric masses.

18. Why will a triple beam balance give the same mass for an object no matter what planet it is on?

19. Define weight.

20. Explain why the weight of an object can change?

21. What is the SI unit for measuring weight?

22. What is gravity?

23. The force of gravity depends on what 2 things?

24. The greater the distance, gravity _________ so weight would be ____________.

25. The more mass an object has, the pull of gravity is _________ so the object will have ___________ weight.

26. How much less gravity does the moon have than the Earth?

27. If you had a mass of 36 kilograms on Earth, what would be your mass on the moon?

28. If you had a weight of 60 Newtons on Earth, what would be your weight on the moon?

29. What planet has 2.5 times more gravity than the Earth?

30. Would your mass be the same on Jupiter? your weight?

31. Define volume.

32. How do you find the volume of a box?

33. The units for the volume of a box would be _________ centimeters.

34. Find the volume of a cube that is 3 cm on all sides.

35. What is the base unit for the volume of a liquid?

36. What scientific equipment is used to measure the volume of liquids?

37. Liquids make a curved upper surface when poured into graduated cylinders, so you must read the _____________ of the curve known as the ________________.

38. In the metric system, 1 cm3 equals __________________ of water having a mass of ________________.

Water Displacement and Density

39. ____________ ______________ is a method used to tell the volume of irregularly shaped objects.

40. If a rock causes the water level in a graduated cylinder to rise from 8.8 to 10 ml, what is the volume of the rock?

41. What is the mass of 25 ml of water? (Hint: look back at your answer to question #38.)

42. What is the mass of 1 liter of water?

43. Define density.

44. When finding the density of an object, the ___________ of an object measured in ___________ is divided by its _____________ measured in ______________ or ______________.

45. What are the units of measurement for density?

46. Sketch the density wheel that can be used to solve density problems.

47. If you know the mass and density, how can you determine the volume using the density wheel?

48. Find the density if the mass of an object is 24 g and the volume is 8 cm3.

49. Find the volume if the density is 3g/cm3 and the mass is 24 grams.

50. Find the mass if the density is 2g/cm3 and the volume is 8cm3 .

51. What is the density of 1 gram of water?

52. What is the volume of .5 kg of water?

53. In terms of density, why do some objects float?

54. Objects with a density less than __________ will float on top of water.

55. A toy boat has a density of 1.5 g/ml. Will the toy boat float?

56. What is true about objects that have a density equal to water?

57. How do fish and submarines that are denser than water float?

58. Why did the Titanic float before it hit the iceberg?

59. Why did the Titanic sink after hitting the iceberg?

Metric System

Metric System (SI)

Scientist use a single, standard system of measurement. The official name of the measurement system is SYSTEME INTERNATIONAL d’UNITES (International System of Measurements) or SI.

The metric system is based on the number 10.

Main Units of Measurement
Length	Volume	Mass
meter (m)	liter (l)	gram (g)

Using the above values (meter, liter, & gram) as the base, their value can be increased or decreased by moving the decimal point to the right (lowers the value) or left (raises the value).

Metric Conversion Table
Kilo- (k)	Base Unit (m, l, g)	Centi- (c)	Milli- (m)	Micro- (µ)	nano- (n)
x 1000	meter, gram, liter	100	1000	1000	1000
1000	1	.01	.001	.000001	.000000001

Convert the following values by moving the decimal point the correct number of spaces and in the right direction .

1. 69.8 meters (m) = ________________ centimeters (cm)

2. 152.97 milliliters (ml) = ________________ liters (l)

3. 42.67 liters (l) = _____________ milliliters (ml)

4. 299.32 kilometers (km) = ____________ nanometers (nm)

5. 26 grams (g) = _____________ kilograms (kg)

6. 123.43 centigrams (cg) = ______________ grams (g)

7. 75.2 liters (l) = __________________milliliters (ml)

8. 456.3 grams (g) = ________________ micrograms µg

9. 4507.22 kilometers (km) = _______________millimeters (mm)

10. 0.00297456 kilograms (kg) = ___________ nanograms (ng)

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Microscope Lab

Learning to Use the Microscope

Introduction

“Micro” refers to tiny, “scope” refers to view or look at. Microscopes are tools used to enlarge images of small objects so as they can be studied. Microscopes range from a simple magnifying glass to the expensive electron microscope. The compound light microscope is the most common instrument used in education today. It is an instrument containing two lenses, which magnifies, and a variety of knobs to resolve (focus) the picture. It is a rather simple piece of equipment to understand and use. In this lab, we are going to learn the proper use and handling of the microscope.

Objectives

Demonstrate the proper procedures used in correctly using the compound light microscope.
Prepare and use a wet mount.
Determine the total magnification of the microscope.
Develop a checklist to insure the proper handling of the microscope.

Materials

Compound microscope
Glass slides
Cover slips
Eye dropper
Beaker of water
The letter “e” cut from newsprint
Scissors

Procedures

Proper Handling of the Microscope

Carry the microscope with both hands — one on the arm and the other under the base of the microscope.
One person from each group will now go over to the microscope storage area and properly transport one microscope to your working area.
The other person in the group will pick up a pair of scissors, newsprint, a slide, and a cover slip.
Remove the dust cover and store it properly. Plug in the scope. Do not turn it on until told to do so.
Examine the microscope and give the function of each of the parts found below.

a. Eyepiece –

b. Body tube –

c. Objectives –

d. Stage –

f. Diaphragm –

g. Coarse adjustment –

h. Fine adjustment –

i. Base –

j. Light source –

Preparing a wet mount of the letter “e”.

With your scissors cut out the letter “e” from the newsprint.
Place it on the glass slide so as to look like (e).
Cover it with a clean cover slip. See the figure below.

Using your eyedropper, place a drop of water on the edge of the cover slip where it touches the glass slide. The water should be sucked under the slide if done properly.
Turn on the microscope and place the slide on the stage; making sure the “e” is facing the normal reading position (see the figure above). Using the course focus and low power, move the body tube down until the “e” can be seen clearly. Draw what you see in the space below.

Describe the relationship between what you see through the eyepiece and what you see on the stage.

7. Offer an explanation of why this happened.

8. Looking through the eyepiece, move the slide to the upper right area of the stage.
What direction does the image move?

9. Now, move it to the lower left side of the stage. What direction does the image move?

10. Re-center the slide and change the scope to high power. You will notice the “e” is out of focus. Do Not touch the coarse focus knob, instead use the fine focus to resolve the picture.

11. Locate the diaphragm under the stage. Move it and record the changes in light intensity as you do so.

Determining Total Magnification:

1. Locate the numbers inscribed on the eyepiece and the low power objective and fill in the blanks below.

Eyepiece magnification ______________

(X)

Objective magnification ______________

Total Magnification _____________X

2. Do the same for the high power objective.

Eyepiece magnification ______________

(X)

Objective magnification ______________

Total Magnification _____________X

3. Write out the rule for determining total magnification of a compound microscope.

4. Remove the slide and clean it up. Turn off the microscope and wind up the wire so it resembles its original position. Place the low power objective in place and lower the body tube. Cover the scope with the dust cover. Place the scope back in its original space on the storage cart.

Summary:

Develop a procedure by which anyone can follow to demonstrate the proper handling of the microscope.

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Microscope Lab

Microscope Lab – Using the Microscope and Slide Preparation

Examine the microscope and familiarize yourself with the parts of the microscope.

1. Magnification

The magnification written on the ocular lens (eyepiece) is _____________

The magnification on the Scanning objective ___________ Low Power Objective ___________
High Power Objective ___________

What is the total magnification for each lens (multiply ocular times objective)

Scanning _____________ Low Power ______________ High Power ________________

2. Diaphragm

Examine the diaphragm, what are the numbers written on it? ____________________

Which setting makes the specimen the lightest? ________________ The darkest? _______________

3. Lenses

Twist the ocular lens, does yours have a pointer? _____________ What is the purpose of the pointer? __________________________________________

Find out what happens to your viewing field if you do not have an objective fully clicked into place. ____________________________________________

4. Viewing a Slide

Obtain a prepared E slide. Focus the slide first with the scanning objective, then click to lower power and focus again. Finally, focus the slide under high power. Remember, at high power, you should ONLY use the fine adjustment knob.

Draw the E exactly as it appears in your viewing field for each magnification. The circles below represent your viewing field. The E should take up as much space in the drawing as it does in your viewing field while you’re looking at it.

Scanning

Low Power

High Power

5. Depth Perception

Obtain a prepared thread slide. You will only need to view it under scanning at this point. Your task is to figure out which thread is on top, which is in the middle, and which is on bottom. You should notice that as you focus the thread, different thread will come into focus at different times. The one that comes into focus the first should be the top thread.

What is the color order of your threads?

6. Making a Wet Mount of a Slide

1. Gather a few strands of cotton from a cotton ball using forceps. If your specimen is too thick, then the cover slip will wobble on top of the sample like a see-saw, and you will not be able to view it under High Power.

2. Place ONE drop of water directly over the specimen. If you put too much water, then the cover slip will float on top of the water, making it hard to draw the specimen, because they might actually float away. (Plus too much water is messy)

3. Place the cover slip at a 45 degree angle (approximately) with one edge touching the water drop and then gently let go. Performed correctly the cover slip will perfectly fall over the specimen.

Draw the specimen as it appears in your viewing field under scanning, low and high power.

Scanning

Low Power

High Power

7. Staining a Specimen

1. Place one drop of stain (methylene blue) on the edge of the cover slip. Caution: Methylene Blue will stain clothes and skin!

2. Place the flat edge of a piece of paper towel on the opposite side of the cover slip. The paper towel will draw the water out from under the cover slip, and the cohesion of water will draw the stain under the slide.

3. As soon as the stain has covered the area containing the specimen, you are finished. The stain does not need to be under the entire cover slip. If the stain does not cover as needed, get a new piece of paper towel and add more stain until it does.

4. Be sure to wipe off the excess stain with a paper towel.

Draw your specimen as it appears under low power. Used color pencils to show how the stain appears. It may appear darker or lighter in spots. Use shading to show darker and lighter spots.

Scanning

Low Power

High Power

8. Investigation of Pond Water

1. Prepare a wet mount of pond water – a sample of pond water is provided in a jar. The best specimens usually come from the bottom and probably will contain chunks of algae or other debris that you can see with your naked eye. (Be careful that your slide isn’t too thick)

2. Use the microscope to focus on the slide – try different objectives, some may be better than others for viewing the slide..

3. Make three separate drawings below at different areas of the slide and at different magnifications. Label where appropriate.

Drawing Specimens

1. Use pencil – you can erase and shade areas
2. All drawings should include clear and proper labels (and be large enough to view details). Drawings should be labeled with the specimen name and magnification.
3. Labels should be written on the outside of the circle. The circle indicates the viewing field as seen through the eyepiece, specimens should be drawn to scale – i.e……if your specimen takes up the whole viewing field, make sure your drawing reflects that.

Scanning

Low Power

High Power

9. Investigation of Large Specimen

Light microscopes are only useful for viewing small thin specimens. In biology, you will perform dissections on larger specimens an may need to magnify the area of interest. In this situation, a stereoscope may be the best instrument. Stereoscopes present a larger field of viewing and handle depth much better than the light microscope. The drawback of the stereoscope is that it does not have a high magnification. Examine one of the stereoscopes in the room. They will be positioned around the room with specimens.

Practice changing the light source and the focus on the stereoscope. For each specimen determine which light and magnification is best for viewing.

Name of specimen ____________________________________________

Magnification _________ Light ____________ Reasons _____________________________________________________________

10. Measuring with a Microscope

Use a clear ruler to determine the width of the viewing field under the scanning objective. Position the ruler so that the millimeter marks are visible in your viewing field. Remember that there are 1000 micrometers in a millimeter.

Estimate the length (diameter) of your viewing field in micrometers _____________________

You cannot use this method to determine the diameter under high power (try switching objectives). Instead you can use a mathematical proportion method to determine the diameter under high power.

High power field diameter = low power field diameter x low power magnification / high power magnification

What is the diameter (in micrometers) of your high power field _____________________

Fill out the table below after viewing prepared specimens.

Name of Object

Measurement of Object

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Metric Conversion Table

Microscope Lab – Using the Microscope and Slide Preparation