Exercise 1: Measurements and the Microscopes Break-out Group Number: Section: Student Names (First and Last) Student Panther ID #s Johana Rodriguez 6173932 Jason Charles 6123334 jiuyi huang 6126684 iffat mahmood 3994473 _____________________________________________________________________________ OBJECTIVES: 1. Understand measurements and conversions of the metric system. 2. Learn how to properly use both compound and dissecting microscopes. _____________________________________________________________________________ INTRODUCTION: Numbers and measurements impact every part of our lives, and are tools that scientists, engineers, astronauts, chefs and doctors use to analyze data, build bridges, fly orbiters into space, adjust recipes, and prescribe medication. Collecting and analyzing data allows us to understand patterns in the natural world that are not easily observed with the naked eye, and the natural variation that is inherent to all organisms is the major reason we need measurements. In today’s lab you will learn about basic measurements and common instruments used by scientists on a daily basis. Your ability to learn and use these concepts will be tested and reinforced throughout the semester. ____________________________________________________________________________ Task 1 - MEASUREMENTS IN SCIENCE: Familiarize yourself with the metric system. Recall from last week that a key component of the scientific method is experimentation. This step is necessary for the collection of data that will either lend support to, or lead to the rejection of, the hypothesis being tested. In general, data can be qualitative or quantitative. Qualitative data describe variables based on quality (e.g. smell, appearance, texture, etc) and are usually gathered through interviews, pictures, field notes and/or surveys. Quantitative data define the quantity of a variable through measurements (e.g. length, area, cost, height, age, etc.). The main disadvantage of qualitative data is that they are often too subjective (what smells good to one individual might not smell equally well to another). Therefore, quantitative data, which can be statistically manipulated and analyzed, are the preferred choice of most scientists because they provide objective, less biased measures. However, we will examine both types of data in greater detail throughout the semester. The metric system is used as the international standard to make measurements worldwide. It is based on units of ten (see Table 1 and 2). In contrast, the Imperial Units of Measurement is based on historical precedent, e.g., a foot was first measured as the length of a man’s foot. Because the metric system is widely employed throughout the scientific arena, it will be covered in this lab. Table 1: Prefix Abbreviation Division or Multiple of Metric Unit Pico p 0.000000000001 Nano n 0.000000001 Micro µ 0.000001 Milli m 0.001 Centi c 0.01 Deci d 0.1 Base unit ----- 1 Deka da 10 Hector h 100 Kilo k ...

1. Exercise 1: Measurements and the Microscopes
Break-out Group Number:
Section:
Student Names (First and Last)
Student Panther ID #s
Johana Rodriguez
6173932
Jason Charles
6123334
jiuyi huang
6126684
iffat mahmood
3994473
_____________________________________________________
________________________
OBJECTIVES:
1. Understand measurements and conversions of the metric
system.
2. Learn how to properly use both compound and dissecting
microscopes.
_____________________________________________________
________________________
INTRODUCTION:
Numbers and measurements impact every part of our lives, and
are tools that scientists, engineers, astronauts, chefs and doctors
use to analyze data, build bridges, fly orbiters into space, adjust
recipes, and prescribe medication. Collecting and analyzing data
allows us to understand patterns in the natural world that are
not easily observed with the naked eye, and the natural variation
that is inherent to all organisms is the major reason we need

2. measurements. In today’s lab you will learn about basic
measurements and common instruments used by scientists on a
daily basis. Your ability to learn and use these concepts will be
tested and reinforced throughout the semester.
_____________________________________________________
_______________________
Task 1 - MEASUREMENTS IN SCIENCE: Familiarize yourself
with the metric system.
Recall from last week that a key component of the scientific
method is experimentation. This step is necessary for the
collection of data that will either lend support to, or lead to the
rejection of, the hypothesis being tested. In general, data can be
qualitative or quantitative. Qualitative data describe variables
based on quality (e.g. smell, appearance, texture, etc) and are
usually gathered through interviews, pictures, field notes and/or
surveys. Quantitative data define the quantity of a variable
through measurements (e.g. length, area, cost, height, age, etc.).
The main disadvantage of qualitative data is that they are often
too subjective (what smells good to one individual might not
smell equally well to another). Therefore, quantitative data,
which can be statistically manipulated and analyzed, are the
preferred choice of most scientists because they provide
objective, less biased measures. However, we will examine both
types of data in greater detail throughout the semester.
The metric system is used as the international standard to
make measurements worldwide. It is based on units of ten (see
Table 1 and 2). In contrast, the Imperial Units of Measurement
is based on historical precedent, e.g., a foot was first measured
as the length of a man’s foot. Because the metric system is
widely employed throughout the scientific arena, it will be
covered in this lab.

3. Table 1:
Prefix
Abbreviation
Division or Multiple of Metric Unit
Pico
p
0.000000000001
Nano
n
0.000000001
Micro
µ
0.000001
Milli
m
0.001
Centi
c
0.01
Deci
d
0.1
Base unit
-----
1
Deka
da
10
Hector
h
100
Kilo
k
1000
Mega
M

4. 1000000
Giga
G
1000000000
Table 2:
Unit (abbreviation)
Measures
Meter (m)
Length
Liter (L)
Volume
Gram (g)
Mass
Degree Celsius (°C)
Temperature
In this task you will practice measuring length, temperature,
volume and mass using the metric system. When taking
measurements, we often need to convert between units. In order
to do this, we must first have information about the size of the
unit we are interested in converting to or converting from. Table
1 provides a partial list of these measures. For example,
suppose we know that the length of a table is 1.5 meters, but we
want to know how many centimeters this corresponds to. Based
on Table 1, we know that the “centi” prefix means 0.01.
Therefore, a centimeter (cm) equals 0.01 (one hundredth) of a
meter (m), or there are 100cm in 1m. To calculate the number of
cm in 1.5m, we can either:
(1) Divide 1.5 by 0.01 � 1.5m x (1cm/ 0.01m) = 150cm or 1.5m
/ 0.01 = 150cm
(2) Multiply 1.5 by 100 � 1.5m x (100cm/1m) = 150cm
In both examples, the meters cancel out, leaving the answer in
centimeters.
I.CONVERSIONS

5. Convert the following measures:
2 meters
=
200
centimeters
=
2000
millimeters
87 millimeters
=
0.087
meters
=
8.7
centimeters
II.MEASURING LENGTH
This sheet is 8.5 inches by 11 inches. Convert these values to
centimeters and then calculate area (in cm) of the page in
centimeters. 1 inch = 2.54 centimeters. Use the conversion table
below to convert our paper dimensions from inches to
centimeters. Calculate the area of the page using metric values.
Width:
8.5 in
X
2.54cm
=
21.6cm
1 in

6. Length:
11 in
X
2.54 cm
=
27.9cm
1 in
Length of our paper:
27.9cm
Width of our paper:
21.6cm
Area of a piece of paper (Area = Width x Length):
60.3cm2
Questions:
1. What are some potential sources of error when making
measurements?
Some of the error sources can be
instrumental,environmental,procedural,and human. All of these
errors can be how they affect the results.
2. Why is it important for all scientists to use a standard system
of measurements?
It is important that other scientists can understand and replicate
the same measurements so that it is true for everyone.

7. III. MEASURING VOLUME
Volume is the space occupied by an object. Units of volume are
usually cubed units of length, but can also be expressed as
divisions/multiples of a liter, i.e., 1L = 1000 cm3 = 1000 mL.
In scientific laboratories, volume is measured using pipettes,
beakers and graduated cylinders. In general, pipettes are used to
measure small volumes (≤ 25 mL), while larger volumes (≥ 25
mL) are measured with graduated cylinders.
When liquid is in a container, the liquid may “respond” to its
container and create a curve. This curve is called a meniscus.
When reading the scale on the side of a container (e.g. a
graduated cylinder), you must account for the meniscus. To
properly read the measurement, hold the container level with
the meniscus at eye level and read the value at the bottom of the
curve.
1. Look at the image to the left of water in a graduated cylinder
with units in mL. Record the volume of water in the space
provided below. Assume the graduated cylinder is level and at
eye level.
36 mL
IV. Mass, Volume, and Density
Water displacement can be used to measure the volume of a
solid object. The following exercise will demonstrate this
process.
Navigate to http://phet.colorado.edu/sims/density-and-
buoyancy/density_en.html
Once the virtual lab is loaded, you should see a pool of water
and a wooden block. You should also be able to see the mass

8. and volume of the block (which you can change using the
sliders), and you should be able to see the density. Finally, you
should be able to see where you can change the material the
block is made of. Let’s start by changing the material to
aluminum.
1. What is the density of the aluminum block?
2.70 kg/L
2. (i) As you increase / decrease the volume of the aluminum
block, what happens to its mass? (ii) What happens to the
volume when you increase / decrease the mass? (iii) What does
this tell you about the relationship between volume and mass of
an object?
i
as the mass increases the volume of the aluminum increases as
well.
ii
as you increase the mass of the aluminum the volume of the
water increases as well.
iii
as the mass increases/decreases the volume will
increase/decrease.
1. (i) Now, instead of using an aluminum block, select “My
Block”. (i) How does the density of “My Block” change in
response to increasing and decreasing mass? (ii) How does the
density of “My Block” change in response to increasing and
decreasing volume? (iii) What does this tell you about the
relationships between mass, volume, and density?
i
If we increase the mass, then the density will also increase
ii
If we increase the volume the density decreases, if we decrease
the volume then the density increases
iii

9. mass is how heavy something is, volume tells how big it is, and
density is mass divided by volume.
3. Now, set the material back to aluminum. Using your mouse,
pick up and drop the aluminum block into the pool of water.
Record the volume of the pool while the block (i) is in the pool,
and when the block (ii) is not in the pool. (iii) How much water
does the aluminum block displace? (iv) What does the amount
of water displacement tell you about the aluminum block?
i
105.00 L
ii
100.00 L
iii
5.00 L
iv
The amount of water displacement tells you the volume of the
aluminum block
We just determined that mass and volume of a material are
related in such a way that increasing or decreasing one causes a
respective increase or decrease in the other. Let’s change the
material of the block back to wood to gain more insight on this
relationship, and their relationship with density.
1. Change the block material to wood.
2. Change the mass of the wood to 2.00 kg (you can manually
type in the mass). What is the volume?
5.00 L
3. (i) How does the volume change if you double the mass of the
wooden block to 4.00kg? (ii)What does this tell you about the
relationship between mass and volume of a material?
i
It doubles the volume to10.00L.
ii

10. the volume of the object is proportional to its mass.
4. How does the density change if you double the mass of the
wooden block from 2.00kg to 4.00kg?
The density remains the same as you change it from 2.00kg to
4.00kg
5. Using your mouse, drag and drop the wooden block into the
pool of water. What happens?
The wooden block floats inside the pool of water
6. How much water does the wooden block displace?
It displaces 2L
7. What does the amount of water displacement tell you about
the wooden block?
It has less density than the other block.
8. What do you think explains the different behavior of wood
and aluminum in water?
Both objects have different densities compared to the water,
higher density will sink, lower density will float.
SUMMARY: Based on these findings, we could say that a
material has a constant, unchanging density. In fact, density of
materials is such a constant that we use it as a defining
characteristic to help identify different materials. And since the
density of a material is an unchanging value, changes in volume
or mass of that material must occur in relation to one-another
such that density remains constant. In other words, a tiny tree
branch will always float on the surface of a large lake, just as a
large tree trunk will float in a swimming pool because, even
though the mass and volume of the wood and water change, they
always change equally so that the density of each material
remains the same. This allows us to develop the following
formula relating (D)ensity, (M)ass, and (V)olume to one

11. another:
D = M/V
Using this equation, if we know the enough about the material,
we can always calculate what we do not know. For example:
1. On your web page in the upper right-hand corner, you can
change the experiment to different types of blocks. Change the
experiment to “Mystery.”
Using the scale and pool of water, calculate the density of
Block A and Block E.
Mass
Volume
Density
Block A:
65.14 kg
3.38 L
19.3 kg/L
Block E:
3.53 kg
1.00 L
3.53 kg/L
2. If you know the density of an object is 3.75 kg/L, and you see
that it displaces 1.50 L of water, how much mass does the
object have?
5.63 kg
3. If you know an object has a density 0.33 kg/L, and you see
that it displaces 5 L of water, (i) how much mass does the
object have? (ii) How much volume does the object have?
i
1.65 kg
ii

12. 5L
V. MEASURING TEMPERATURE
Temperature is the amount of heat present in a particular
substance, and it is recorded in degrees Celsius (oC). The
Celsius scale is based on water freezing at 0 oC and boiling at
100 oC. To convert between Fahrenheit and Celsius the
following equations are used:
F = C (1.8) + 32 or C = (F – 32) /1.8
Using the internet, determine today’s sea surface temperature
for San Francisco Bay, California in Fahrenheit. Using the
formula above, calculate what that temperature is in Celsius. Do
the same thing for the city of San Francisco. Record your
answers below in Table 6.
Table 6:
Object
Temperature (°C)
Temperature (°F)
SF Bay
22.22
72
SF City
10.8
51.4
_____________________________________________________
________________________
Task 2 - USING THE MICROSCOPE

13. Microscopes are tools used to examine specimens too small to
be observed with the naked eye. There are two types of
microscopes that you will use in this lab, compound light and
dissecting microscopes. In general, a compound light
microscope is used to visualize very small items (e.g. blood
cells) while a dissecting microscope is used for observing much
larger items (e.g. mouthparts of a grasshopper).
A. Familiarize yourself with the use of the light microscope
1. Navigate to the following website, which will simulate using
a compound microscope
https://www1.udel.edu/biology/ketcham/microscope/scope.html
2. Identify each part labeled on the compound microscope in
Figure 4 and note its function in Table 7:
Oculars
Body Tube

14. Nosepiece
Arm
Objective
Slide Holder
Stage Clip
Coarse Focus
Adjustment
Stage
Fine Focus
Adjustment
Condenser iris diaphragm
Substage
Lamp

15. Field Iris
Diaphragm
Base
Figure 4. Major parts of a compound light microscope
Table 7:
Part
Function
Objective lens
Responsible for magnifying the image of a specimen 10x, 40x,
100x
Stage
Flat surface where the slide with the specimen is placed
Condenser Iris Diaphragm
Condenser: Collects light from illuminator and focuses it on the
specimen
Iris Diaphragm: Controls the amount of light reaching the
specimen
Substage Lamp
Light on the bottom of the stage
Oculars
Where you look through to see the specimen. Also helps
magnify the image
Arm

16. Connects to the base and helpful for carrying the microscope
Coarse Focus Adjustment
Moves the stage up and down to bring the image into focus
Fine Focus Adjustment
Part of the coarse adjustment, brings the image into sharp focus
3. Follow the voice-guided tutorial to familiarize yourself with
the microscope controls and view options.
Questions:
a. View the letter e slide under the scope.
b. (i) Draw the letter e below as you view it through the
microscope with the lowest power objective. (ii) As you view
the letter e, how is it oriented? Upside down or right side up?
(iii) What does that tell you about how the microscope
processes the image?
i
e
How to draw: Place your cursor in the cell to the left. Click on
Insert>Drawing>+New>Select Line>Scribble. Now draw what
you see with your mouse. When done choose save and close.
ii
is oriented upside down
iii
they process the image like a mirror, you see the image is
flipped.
c. Observe how the image moves when the slide is moved to the
left or right.
when the image moves to the right when the slide moves to the
left and vice versa.
d. What happens to the brightness of the view when you switch

17. from the 4X to the 10X objective?
The brightness gets brighter.
B. Magnification
1. Examine your microscope. (i) What do the numbers on the
objectives mean? Assume that you see the number 10x on your
oculars. (ii) What do you think that means?
i
ii
2. Calculate the total magnification (objective magnification x
ocular magnification) for each objective (4x-40x) and record in
Table 8 below.
Table 8.
Objective Magnification
Ocular Magnification
Total Magnification
4 X
10 X
40 X
10 X
10 X
100 X
40 X
10 X
400 X
Questions:
a. How many times is the image of the e magnified when it is
viewed through the highest power objective lens?
10 X, was the objective used to be able to see clearly the “e”
image.
b. If you didn’t know what you had on your slide (an e) and you

18. began examining it at the highest power, how could you
determine it was an e?
First, start from the lowest magnification and increase the
magnification until you are able to see the image clearly.
C. Field of View
The field of view is the area you can see when you look through
the lens of a microscope (Fig. 5). Understanding the size of this
field under different magnifications is important because it
allows you to estimate the size of objects in your view. The
following procedure demonstrates the determination of field of
view (FOV) under various magnifications.
Procedure:
1. Click on the “Try this” button, and then select the “m1”
slide.
Figure 5: Field of view under various magnifications
2. Following the instructions, try to calculate the height of the e
from top to bottom.
150 micrometer
3. Follow the similar instructions for the m2 and m3 slides.
m2
8 micrometer
m3
2 micrometer
Questions:

19. a. Discuss the advantage and limitation of viewing specimens
under highest magnification.
Advantage
An increase in detail can be viewed
Disadvantage
Less of the slide is able to be seen
b. What about the low-power objective?
Advantage
Covers a wide field of view
Disadvantage
Smaller parts of a specimen cannot be fully viewed
D. DEPTH OF FIELD
The depth of field is the difference in distance of the nearest
object in focus on a plane and the furthest object in focus on a
plane. The following procedure will demonstrate how to use the
microscope to determine the depth of the field of view.
1. Navigate to
https://www.youtube.com/watch?v=kJZh9wY37UM
2. (i) As the instructor adjusts the focus, what do you notice
about the strings in view? (ii) Can you identify the order that
the strings are layered from top to bottom?
i
the focus can only focus on one string at a time.
ii
blue, red, yellow
Questions:
a. How does depth of field affect viewing specimens that are

20. thick?
The depth of field allows us to study properly microscopic
structures in three dimensional ways.
b. (i) Are all three threads visible under the low power? (ii) Can
they all be seen at the same time under higher power?
i
low power provides the greatest depth of field.
ii
no,because of the narrow depth field.
c. Which objective provides the greatest depth of field?
low power
E. Preparing Wet Mounts of Biological Specimens
1. Navigate to
https://www.youtube.com/watch?v=RfaSyfDBQzU. Take note
how the instructor prepares a slide for viewing under the
microscope. This prepared slide is called a wet mount
MICROSCOPE TIPS:
This is an air bubble, NOT your specimenThese are cotton
fibers, not your specimen

21. 2. Next, navigate to https://www.youtube.com/watch?v=Sb-
gf0e534k. (i) As you watch the video, note the diversity of
organisms you see. As you observe the microorganisms, (ii)
why do parts of some of them move in and out of focus, while
other parts remain in focus?
i
ii
F. Dissecting Microscope
1. Navigate to
https://www.youtube.com/watch?v=JNCeBBwfb_0
2. Observe the demonstration on how to use a dissection
microscope.
3. What are some major differences between compound
microscopes and dissection microscopes?
dissection microscope is used to watch living organism. while
compound is used to see dead organism or bacterias.
4. When would you use a dissection scope instead of a
compound microscope?
RAN OUT OF TIME HERE .
Ocular Lens

22. Zoom
Magnification Adjustment
Arm
Focus
Adjustment
Transmitted Light Source
Stage
Base
Figure 6.Major parts of a dissecting microscope
G. Comparison of Compound and Dissecting Microscopes

23. Compare the two types of microscopes we examined today in
Table 9.
Table 9:
Characteristic
Dissecting Microscope
Light Microscope
Magnification
Resolution
Size of field of view
Depth of field
Orientation of Specimen (Letter e’s)
INSTRUCTIONS FOR ASSIGNMENT

24. BSC 2010L Asynchronous Week Midterm Study Guide
TOPICS FOR STUDY GUIDE
Lab 1 – Measurements and Microscopes
● Conversions
● Density and Volume Displacement
● Compound Microscopes vs. Dissecting Microscopes
● Wet Mount Slides
● Depth of Field / Field of View
● Magnification
● Other Relevant Topics
Your notes can be written in whatever format you believe is
clearest (bullet points, T-charts,
brief paragraphs etc.) but each lab should consist of roughly 2
pages of notes minimum. Length
will vary based on note format so it may be more helpful to
think of this in terms of amount of
time this should take. This assignment is intended to take the
place of our in-person class
meeting and should take you roughly the same amount of time
as a typical lab might. You should
spend approximately 2 hours creating notes for your section in
order to make sure they are
complete and accurate. This study guide is what you and your

25. group members will use to study
for the midterm, so if you miss any important information, you
will lose points. Please be
thorough. Notes MUST be in your own words. Simply copying
and pasting from lab
materials or the internet will be considered plagiarism. If you
are copying images, figures,
etc make sure to note where those were pulled from to avoid
plagiarism. Notes should be typed
and organized in “Word-Document” format.
Be advised that if your notes are unclear, incomplete, lacking in
accuracy, or insufficient in
length that you will not receive full points on this assignment.
This assignment is worth 20
points, but it is to your own benefit to complete it as detailed as
possible, since this content will
form the basis for your midterm exam, which is worth nearly ¼
of your grade for this class at
230 points.