Microscopic Life

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Transcript Microscopic Life

Microscopic Life
Investigation Three
Elodea
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Elodea is a aquatic plant.
Turn to page 15 in your packet. Read
directions.
Create a wet mount of the elodea leaf.
One person will bring a slide, dropper,
coverslip, and forceps to the back counter.
Place materials on a paper towel.
Identify your pond and place half of an elodea
leaf on your slide using the forceps. Add 2-3
drops of pond water and cover slide with a
coverslip. Dry, wash and secure all materials.
Return to your table. Complete Part 1 and 2.
Elodea Discussion Questions
1. What do you see when you look at the
Elodea?
2. When you focus up and down through
the leaf sample, what did you notice?
3. Are the rectangles flat, like designs
drawn on the surface of the leaf, or are
they three dimensional?
4. Are the boxes empty?
5. How many layers of these “bricks” do
you see?
Cell Size
6. What are the boxes or bricks that you see on
the Elodea leaf?
7. Are all of the cells on the Elodea leaf the
same size?
8. How many layers of cells are there in an
Elodea leaf?
9. Are the large cells on the top of the leaf or
the bottom?
10. How big are the Elodea cells?
11. Did you notice anything moving inside any
of the cells? What did it look like?
ELODEA NOTES
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Cells are the basic unit of life. The
boxes or bricks that you see on the
Elodea leaf are cells. Cells are the
units from which the Elodea leaf is
made.
Cells are filled with a fluid called
cytoplasm. Cytoplasm can sometimes
be seen moving inside the cells of
living plants.
The green balls moving in the
cytoplasm are chloroplasts. They
give green plants their color.
Part 2 and 3
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What else was in the elodea slide? Were
they alive?
What makes you think they are/are not
alive? What’s your evidence?
What do you think they are?
Complete Part 2 and 3 on p. 15.
Make sure you write down and draw
exactly what you see in the field of
view.
Discuss observations with table.
Wet Mounts of Paramecium
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View Lab Techniques/CD ROM
Bring slide, dropper, cotton ball, and
coverslip to the back sink. Work on
top of the paper towels, take one drop
of pond water and add it to the slide.
Pull a few pieces of cotton filament
from the cotton ball and place it onto
of the pond water. Put coverslip on
top and return to your table.
Paramecium – single celled
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What movements did you observe?
What did you see on the inside of the
paramecium?
What did you see on the outside of the
paramecium?
How big was it at 100x? 400X?
Are they living or nonliving? What is your
evidence?
Could you see if it was doing all of the things
you have listed in your definition of a living
organism?
Did you see it eat or use energy? Give
waste? Reproduce? Etc…
What might we do to see some of these
activities?
Elodea vs Paramecia
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What did the microscopic structure of
the elodea look like?
What did the microscopic structure of
the paramecium look like? Did it look
like it was made out of cells?
Do the things inside of the paramecium
look like the things inside the elodea
cells?
What were some similarities and
differences?
Paramecium vs Elodea Facts
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Paramecia are single celled organisms.
Just like the individual green “bricks” in the
Elodea are individual cells, each paramecium
is an individual cell.
The Elodea plant is an organism. It is made
of many cells and it is a multicellular
organism.
The paramecium is an organism. It however,
has one cell, single-celled organism.
Paramecia and other single celled organisms
belong to the kingdom of life called Protista.
Some common protist are ameba, euglena,
and flagellates.
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The Elodea plant and the individual
paramecium cell are both organisms
because they can live on their own.
The individual Elodea cell, although it
shows signs of life, is not an organism.
Evidence: The Elodea cells stay in one
place; paramecium move around. Elodea
cells are stuck together; paramecium
are alone.
Elodea cells are part of a bigger
organism; paramecium are not.
An organism is always free-living. It is
not a part of a larger living organism.
Characteristics of Cells
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Cells are alive.
Life happens in cells and only in cells.
Some cells live alone while others live
with millions of others, like the Elodea
leaf cells.
Not all cells are organisms, because
not all cells are able to live
independently.
An organism, single or multi-celled,
can do all characteristics of life.