CELLS UNIT
The Big Ideas
Do your best to ANSWER the questions below in the text box or at least write
down anything you know that it is related to the question. By the time we finish,
you should be able to easily answer all of them.
How does the structure of a cell help it to live?
How are plant and animal cells different?
How do materials get into and out of a cell?
How do plant and animal cells depend upon each other?
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Cell Theory - Guided Reading
BENCHMARK
7CE-1.2 State the cell theory and describe its development
Directions: READ pages 6 - 11 in your green Cells and
Heredity textbook and ANSWER the following questions as you
go along.
What are cells?
Explain the importance of Robert Hooke's contributions to the
cell theory.
Explain the importance of Anton van Leeuwenhoek's
contributions to the cell theory.
Cell Theory - Guided Reading (Continued)
Explain the importance of Matthias Schleiden and Theodor
Schwann's contributions to the cell theory.
Explain the importance of Rudolf Virchow's contributions to the cell
theory.
What three things does the cell theory state?
CELL THEORY
CELLS: THE BASIS OF LIFE
READ the following statements:
cells.
Robert Hooke (1635-1703) looked at thin slices of cork
under the microscope.
microscope.
bee.
an scientists developed what we now call the cell theory.
FOLLOW the reading instructions below:
HIGHLIGHT the name of the man who first saw cells through the microscope.
HIGHLIGHT the type of cell he was looking at.
UNDERLINE the sentence that explains where the name cells came from.
PUT A STAR NEXT TO the year that the nucleus was discovered.
PUT A BOX AROUND the nationality of the two scientists who first developed the "Cell
Theory".
READ the Biography of Robert Hooke on the next page and ANSWER the following question:
What was special about Robert Hooke and his book Micrographia?
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CELL THEORY
Biography of Robert Hooke
When Hooke published his great book Micrographia, it caused an immediate sensation and was
perhaps the first popular science book in history. The famous diarist Pepys obtained a copy as soon
as he could, and wrote,
"Before I went to bed I sat up until two o'clock in my chamber reading Mr. Hooke's
Microscopial Observations, the most ingenious book that I ever read in my life."
Hooke was probably the first scientist to use the microscope to study life in microscopic detail.
Using a compound microscope that he made for himself, he studied organisms as diverse as insects,
sponges and foraminifera (single-celled organisms with shells). Micrographia is a detailed record of
his observations, and includes his own superb drawings of what he saw through his microscope. He
was the first to see clearly such things as the scales on a flea‟s body and the minute hairs on a fly‟s
leg.
His most famous observation was of thin slices of cork, of which he wrote,
"I could exceedingly plainly perceive it to be all perforated and porous, much like a
honeycomb, but that the pores were rectangular. These pores, or cells were indeed the
first microbial pores I ever saw, and perhaps, were ever seen"
In fact, as we know now, Hooke had discovered living cells, which he named because they
reminded him of cells in a monastery.
Hooke also studied fossils and noted the similarities between petrified wood and fossil shells and
living wood and shells, and went on to make the first description of the process of fossilization, in
which minerals gradually replace living tissues to turn dead organisms into stone.
He later went even further, suggesting that seashell
fossils found in high mountains indicate the in the past
the world was subjected to massive earthquakes which
threw up ancient sea beds to form mountains. Hooke
even thought that some of these fossils might be of
species of creatures that no longer existed. Such ideas
were way ahead of their time, and only became popular
in the great revolution which transformed geology and
formed the basis of Charles Darwin‟s theory of
evolution almost 200 years later.
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MICROSCOPE MANIA
TASK 1 - LEARNING THE NAMES OF THE MICROSCOPE
LABEL the microscope diagram using the names at the bottom of the sheet.
CREATE the names into the correct spaces.
COMPARE your answers with the answers of a partner after you both finish
CHECK the answer copy when you have finished.
CORRECT if necessary.
Can you label the parts
of the microscope?
Microscope
Mania
Labels for Microscope Parts
Stage Controls
Base
Light Source
Objective Lens
Neck
Nosepiece
Fine Focus
Observation Tube
Eyepiece
Iris Diaphragm
Stage
Coarse Focus
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MICROSCOPE MANIA
- GUIDELINES FOR DRAWING A GOOD CELL DIAGRAM
1. Take turns READING each statement below to your 1 o'clock partner :
Title - Write the title of the type of cell and underline it with a ruler if there‟s no line already.
Number of Cells - Pick three or four cells and draw them LARGE to show as much detail
as possible - Mark on your diagram if they are drawn to scale or not.
Where to Draw - Draw the cells while you are still at your microscope, NOT when you are
back at your table.
How to Draw & Label - Draw carefully and neatly with a pencil. Label the parts that you
know.
Observations - Write down the observations of the cells next to the diagram. Include color,
shape, any movement, are they connected, what do you see inside, etc.
Magnification - Write down the magnification that you are using.
To CALCULATE magnification you need to MULTIPLY the magnification of the eyepiece and the
magnification of the objective lens:
TYPE OF LENS
MAGNIFICATION
ANSWER the following questions:
Eyepiece
Low power
x10
x4
1. Looking at the diagram on the next page and the
magnification used, which objective lens (low,
medium, or high power) was used on the
microscope to draw this? ___________________
(red line on lens)
Medium power
(yellow line on lens)
High Power
(blue line on lens)
x10
x40
2. If a low power lens was used to see cells, what
would the magnification be? ________________
2. LOOK at the cell diagram on the next page.
3. COMPLETE the chart below:
WHAT IS CORRECT ABOUT THIS
DIAGRAM?
WHAT COULD BE IMPROVED?
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MICROSCOPE MANIA
TASK 4 - GUIDELINES FOR DRAWING A GOOD CELL DIAGRAM
4. GRADE the sample cell diagram using the rubric below.
CELL DIAGRAMS RUBRIC
Excellent (3 points)
Satisfactory (2 points)
Needs Work (1 points)
Missing or Unacceptable (0 Points)
Sample Cells
Score
All diagrams have a title that clearly shows what type of cell is being drawn (1 point possible)
A SMALL number of cells are drawn with large, detailed drawings using pencil.
Detailed observations are written / Diagram labeled when appropriate
Magnification used is noted (40x, 100x, 400x) (1 point possible)
Overall work is well done and neat
TOTAL
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TASK 5 - PRACTICING HOW TO USE THE MICROSCOPE
1. ASK your teacher for a prepared slide.
2. FOCUS on low, medium, and high power.
3. If you finish all six tasks early, prepare a slide using the letter "e" for more practice.
TASK 6 - DRAWING GOOD CELL DIAGRAMS WITH CORRECT MAGNIFICATION
1. FOLLOW the "Guidelines for Drawing a Good Cell Diagram" from Task 4 to DRAW a cell diagram of the
prepared slide.
CELL DIAGRAM
Observations
Color:
Shape:
Movement:
Connected?
What‟s inside?
Other:
Drawn to Scale?
Magnification =
2. ASK your 1 o'clock partner to CRITIQUE your diagram using the rubric.
CELL DIAGRAMS RUBRIC
Excellent (3 points)
Satisfactory (2 points) Needs
Work (1 points)
Missing or Unacceptable (0 Points)
Prepared
Slide
All diagrams have a title that clearly shows what type of cell is being drawn (1 point possible)
A SMALL number of cells are drawn with large, detailed drawings using pencil.
Detailed observations are written / Diagram labeled when appropriate
Magnification used is noted (40x, 100x, 400x) (1 point possible)
Overall work is well done and neat
TOTAL
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