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The following instructional plan is part of a GaDOE collection of Unit Frameworks, Performance Tasks, examples
of Student Work, and Teacher Commentary. Many more GaDOE approved instructional plans are available by using
the Search Standards feature located on GeorgiaStandards.Org.
Georgia Performance Standards Framework for Biology 9-12
Unit: Organization
General Task
How Are Cells Differentiated?
Overview: Making microscopic observations of different types of cells, students will compare
and contrast cell organelles and their functions and relate how these structures maintain
homeostasis in all living things.
Standards (Content and Characteristics):
SB1.
Students will analyze the nature of the relationships between structures and
functions in living cells.
a. Explain the role of cell organelles for both prokaryotic and eukaryotic cells,
including the cell membrane, in maintaining homeostasis and cell reproduction.
SB3.
Students will derive the relationship between single-celled and multi-celled
organisms and the increasing complexity of systems.
b. Compare how structures and function vary between the six kingdoms
(archaebacteria, eubacteria, protists, fungi, plants, and animals).
d. Compare and contrast viruses with living organisms.
SCSh2. Students will use standard safety practices for all classroom laboratory and field
investigations.
a. Follow correct procedures for use of scientific apparatus.
b. Demonstrate appropriate technique in all laboratory situations.
c. Follow correct protocol for identifying and reporting safety problems and
violations.
SCSh4. Students use tools and instruments for observing, measuring, and manipulating
scientific equipment and materials.
a. Develop and use systematic procedures for recording and organizing information.
SCSh5. Students will demonstrate the computation and estimation skills necessary for
analyzing data and developing reasonable scientific explanations.
d. Consider possible effects of measurement errors on calculations.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology 9-12  Organization
August 17, 2007  Page 1 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
Enduring Understandings:
• Cells have particular structures that underlie their functions.
• Regardless of cell type, cellular components function together to maintain homeostasis.
• All organisms and systems are organized from simple parts into complex systems that
must maintain homeostasis in order to survive.
Essential Questions:
1. How are unicellular and multicellular organisms similar and different?
2. How are prokaryotic and eukaryotic cells similar and different?
3. How do organelles work together to maintain homeostasis in the cell?
4. Why is cell differentiation necessary for the survival of multicellular organisms?
Pre-Assessment:
Placemat Activity:
Group students into 4, have a placemat for each group. The placemat can be a piece of butcher
paper divided into four sections. Label sections as : Characteristics of Eukaryotes, Examples of
Eukaryotes, Characteristics of Prokaryotes, Examples of Prokaryotes. Give students 5 minutes
to brainstorm as much as they know for their placemat. See Placemat template below. A
different placement could be created to pre-assess student knowledge of the characteristics and
types of plant and animal cells.
Outcome /
Performance
Expectations:
•
•
•
General Teacher
Instructions:
Materials Needed:
Compare cell types and describe the function of individual cell
organelles in cell functioning and reproduction
Describe homeostasis as involving the transport of materials in a
cell and in an organism
Explain the role and mechanisms of homeostasis in maintaining
life as they relate to cell structure
This activity will take approximately two full block periods. The
instructions in this lab may need to be adjusted depending on the type of
microscopes available for student use (compound microscope or digital
microscope) and the skill levels of your students.
The focus of second part of this activity is to compare structures from
multi-cellular organisms with those of the less complex organisms. The
students are NOT to be assessed on the different types of cells. The
assessment should be on the organization necessary for the complex
organisms to carry out the life processes and survive.
Part 1
• Compound microscope or digital microscope
• prepared slide of bacteria
• Methyl blue
• paper towel
• ruler (clear)
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 2 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
Safety Precautions:
Task with Student
Directions:
• Elodea or Lettuce
• Yogurt with “active” culture
• 2 slides and coverslips
• Iodine stain
• Onion
• eyedropper
• Cover slips
• Toothpicks
• Prepared slides of human epithelial tissue.
Part 2
• Compound microscope
• Prepared slides
• Leaf (cell types vary in the formation of this organ, lead students to
see the variety of cells)
• Stem (either monocot or dicot, do not focus on the difference
between these two, the focus is on differentiation of cells)
• Root (meristem)
• Epithelial
• Cardiac muscle
• Nerve
• Smooth muscle
• Bone
• Follow correct microscope handling directions.
• Follow glass safety rules (handling slides/ slip covers)
• Follow chemical safety rules for toxic chemicals
• Wear goggles and aprons.
• Methyl blue and Iodine stain clothes.
Procedures:
All students should complete the following sections and put all
observations, measurements and calculations in their lab notebooks.
Part 1
1. Measuring the field of view:
•
Turn on the microscope's light source.
•
Adjust the amount of light for your eyes using the diaphragm
located underneath the stage.
•
Calculate the total magnification of each objective by
multiplying the power of the objective (the even number printed
on the objective) by the ocular (the number that has an "x"
behind it printed on the eye-piece). Record value in a data table.
•
Place a clear ruler on the stage and determine the diameter of the
field of view while using the low power objective (generally
10x). Record value in a data table.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 3 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
•
Calculate the diameter of the high power field of view by
dividing the low power field of view diameter by the number of
times the low power magnification can be divided into the high
power magnification. Record value in a data table. Example: If
the low power field of view is 2mm or 2000 microns, the low
power magnification is 10x and the high power magnification is
40x, then the high power field of view is 2000 microns divided
by 4 = 500 microns. Record value in a data table.
Teacher note: The
small size of bacteria
may prohibit direct
student observations.
2. Viewing Prepared Slides:
Set up a station for
students to view
Bacteria Place the prepared slide of bacteria on the stage of the
bacterial cells
microscope.
(prepared slide).
• Using the low power objective (usually 10x) find and focus on
Have a poster or
some bacteria cells.
some other visual aid
• Adjust the slide so that the bacteria cells are in the center of
showing the structure
the field of view.
of a bacterial cell.
• Using the ruler determine the distance between the bottom of
the objective and the slide and record the information on the
data sheet.
• Adjust the microscope to high power (not the oil immersion
Teacher note: the
objective) and refocus on the cells. If necessary re-adjust the
size of a single cell
position of the cells so that they are again the in center of the
can be determined by
field of view.
dividing the diameter
• If your microscope has an oil immersion objective (100x),
of the field of view by
adjust the microscope to oil immersion with the assistance of
the approximate
your teacher and again refocus and adjust the position of the
number of cells that
cells if necessary.
fit across that
• Draw a circle on the data sheet to represent your field of view
diameter.
at this magnification then draw several bacteria cells in that
circle. Indicate the total magnification that you are using and
estimate the size of one of the cells.
Teacher note: Skin
cells from the
underside of the wrist
can be obtained with
a small piece clear
tape eliminating the
use of toothpicks.
The tape can be
placed directly on a
slide and stained as
described.
Human epithelial cells Slide:
If necessary, the teacher can prepare the human epithelial slide
and have it setup for students to view. Gently scrape the inside of
the cheek with a toothpick. Wash cells from toothpick to slide
using a pipette of distilled water, or stir toothpick into a drop of
water on a slide. Dispose of toothpick properly. Add a coverslip.
Add iodine or methyl blue by drawing the stain under the
coverslip using a paper towel.
•
Place the prepared slide on the stage of the microscope.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 4 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
•
•
Teacher note:
Instruct students to
dip only the tip of a
toothpick into the
yogurt, and transfer
that small drop onto
the slide.
Observe the cells as you have done in the previous portions of
this activity. Record your observations on the data sheet.
Again after making the circle in the space, make a drawing of
the cell and label all of the structures that you see. Indicate the
total magnification you are using and estimate the size of one
of the cells.
3. Preparing Your Own Slides:
• Slide One: Yogurt
• Place a very small dollop of yogurt on a microscope slide.
• Mix the yogurt in a drop of water, add a coverslip, place the
slide on the stage of a compound microscope.
• First focus using the low-power objective.
• Then, rotate to the high-power, and focus.
• Finally, use the oil immersion objective to
• Draw a perfect circle in the space on the data sheet to
represent your field of view at this magnification and draw
three cells (labeling all the parts that you can see) in that
circle. Give as much detail as you can. Indicate the total
magnification and estimate the size of one of the bacteria cells.
• Slide Two: Onion
• Place a drop of water in the middle of a clean slide.
• Remove a section of the skin from the inside layer of the onion
and place it on the slide in the drop of water. Make sure the
skin is smooth and is not folded or twisted.
• Place the cover slip over the top by placing the edge of the
cover slip on the end of the drop of water, and then gently
lower the cover slip down on the drop of water.
• Observe through the microscope (by first using low-power and
working up to high-power). Are any of the organelles moving?
Record your observations on the data sheet.
• Draw a perfect circle in the space on the data sheet to
represent your field of view at this magnification and draw the
cells you see (labeling all the parts that you can see) in that
circle. Give as much detail as you can. Indicate the power that
you are using and estimate the size of one of the cells.
• Place one drop of iodine on the slide just to the side of the
cover slip. Using a small piece of paper towel on the opposite
side, draw the stain under the cover slip. Let the slide set for 3
minutes letting the iodine stain the cells.
• Again observe the cells through the microscope.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 5 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
•
•
Draw a perfect circle in the space on the data sheet to
represent your field of view at this magnification and draw the
cells you see (labeling all the parts that you can see) in that
circle. Give as much detail as you can. Indicate the total
magnification and estimate the size of a single onion cell.
Clean and dry the slide and cover slip when done.
• Slide 3: Elodea
•
•
•
•
•
Place a drop of water on the slide again, and put an Elodea leaf
or a small piece of leafy lettuce in the water.
Put the cover slip in place as you did before and observe the
leaf through the microscope (again going from the scanning
objective to high-power).
Observe the cells. You may have to use a lower power to see
all of one cell at a time.
Again after making the circle in the space, make a drawing of
the cell and label all of the structures that you see. Indicate
total magnification and estimate the size of a single Elodea
cell.
Clean and dry the slide after your observations and data
collection.
Complete the following analysis items using the drawings and data
collected over the two days.
Analysis:
• Indicate the diameter of the field of view of low and high power
• Calculate the total magnification power of the microscope with
each objective.
• Give the size of the cells observed (estimated) and indicate the type
of cell each represents
Bacteria (prepared)
Bacteria (yogurt)
Onion
Elodea or Lettuce
Human skin cell
•
Visit this website:
http://www.tulane.edu/~dmsander/Big_Virology/BVHomePage.
html
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 6 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
• Pick a virus from the website and sketch a diagram of
your virus. Label the parts and give their function.
• Compare the structure of a virus to that of a cell.
• Compare the size of virus to that of a cell and an
organelle( ribosomes, for instance.)
• Compare eukaryotic and prokaryotic cells using a graphic
organizer.
• Compare plant and animal cells using a graphic organizer.
• From the estimated cell size, have the student measure their height
and width to determine how many cells it would take to make a
body their size. Show calculations.
• Make a composite drawing of the largest cell observed with the
other cells drawn inside of it in proportion to see that many
bacteria cells can fit inside a human cell.
•
In an essay type format, students will compare and contrast the
cell organelles and their functions to the single-celled organisms
and how these structures maintain homeostasis in all living
things. Students should also include a diagram (flow chart) of
how organisms are organized. Students will need to include in
their discussions why multi-cellular organisms require
differentiation to maintain homeostasis.
Inquiry Using the Digital Microscopes
Part I.
All students will show proficiency with the microscope (either digital or
compound) prior to completing the activity by:
Measuring the field of view:
• Turn on the microscope's light source.
• Adjust the amount of light for your eyes using the diaphragm
located underneath the stage.
• Place the clear ruler on the stage and determine the diameter of
the field of view while using the low power objective (the
shortest one). Record value in a data table.
• Adjust to high power (do not use the oil immersion objective –
100x) and calculate the diameter of its field of view using the
directions provided above. Record value in a data table.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 7 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
•
Calculate the total magnification of each objective by
multiplying the power of the objective (the even number printed
on the objective) by the ocular (the number that has an "x"
behind it printed on the eye-piece). Record value in a data table.
Part 2
Provide students with a variety of prepared slides of both prokaryotic
and eukaryotic cells as well as materials to make their own slides.
Using the digital microscope each group will:
Capture and save an image of each of the following:
• Prokaryotic Cell
• Eukaryotic Cell
• Plant Cell
• Animal Cell
• Bacteria Cell
Place the images and the following information into a multimedia or
word processing document. Incorporate the information listed below.
• Type of cell
• Magnification used when image was captured
• Size of each cell
• Label any organelles visible
• Method for preparing each slide
• Create a graphic organizer to compare eukaryotic and prokaryotic
cells
• Create a graphic organizer to compare plant and animal cells
Resources:
Homework /
Extension:
Conclusion:
In an essay type format, students will compare and contrast the cell
organelles and their functions to the single-celled organisms and how
these structures maintain homeostasis in all living things. Students
should also include a diagram (flow chart) of how organisms are
organized. Students will need to include in their discussions why multicellular organisms require differentiation to maintain homeostasis.
http://cellsalive.com/
http://www.tulane.edu/~dmsander/Big_Virology/BVHomePage.html
Students complete Cell_Venn Diagram –ORHave students visit this website: http://cellsalive.com/
• Research organelles and determine the basic functions of
each organelle.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 8 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
•
Instructional Task
Accommodations for
ELL Students:
•
•
•
•
•
•
•
In a paragraph, describe the role each organelle plays in
maintaining homeostasis in the cell.
Pair with more advanced native language speaking partner
(allow for translation in native language for comprehension) as
needed
Provide paragraph summary template ( fill in the blank format)
Provide bilingual support using word to word translation such as
dictionaries, and glossaries
Provide native language text books and support material
whenever possible
Keep language simple, eliminate unnecessary text, modify
difficult text ( use visual representations of texts
Give a written example of what observations measurements and
calculations in their lab notebooks should look like
Highlight / or color code key points in directions of microscope
viewing, measuring, and calculating
Instructional Task
• Review and Implement IEP accommodations for specific
Accommodations for
student needs
Students with
Specific Disabilities: Other Accommodations may include
•
•
•
•
Instructional Task
Accommodations for
Gifted Students:
•
•
Word banks, and /or sentence starters for written lab report
Provide step by step check off sheet for activities
Verbal responses to explain student’s detailed drawings and or
graph
Highlight / or color code key points in directions of microscope
viewing, measuring, and calculating
Students may view, measure, and make calculations of
additional cell types and record in lab notebooks
Research size of viral particles; include drawing of a virus
indicating the appropriate scale.
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 9 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
Pre-assessment Placemat Template:
Characteristics of Eukaryotes
Examples of Prokaryotes
Examples of Eukaryotes
Characteristics of Prokaryotes
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 10 of 11
Copyright 2007 © All Rights Reserved
One Stop Shop For Educators
Georgia Performance Standards Framework for Biology 9-12
Cell Venn
Make a Venn diagram using the following organelles for prokaryotic and eukaryotic cells. Then
use the same organelles for plant and animal cells.
1.
2.
3.
4.
5.
cell membrane
cell wall
nucleus
ribosomes
cytoplasm
Prokaryotic Cells
Plant Cells
6. endoplasmic reticulum
7. vacuole
8. mitochondria
9. chloroplast
10. lysosomes
Eukaryotic Cells
Animal Cells
Georgia Department of Education
Kathy Cox, State Superintendent of Schools
Biology  9-12  Organization
August 10, 2007  Page 11 of 11
Copyright 2007 © All Rights Reserved