Cell Lab
Name ____________________________
Introduction: Cells are the basic unit of life. Specific cell parts often are best studied by observing certain living
or once living materials. Cell walls are observed in cork cells. Cell membranes and cytoplasm are observed easily
in cheek cells. These same specific cell parts can be found in other types of cells also.
Objectives In this lab investigation you will:
1) Observe a variety of lining and once living materials under the microscope
2) Determine if these materials do or do not show a cellular type of organization
3) Study specific cell parts – the cell wall, cell membrane, cytoplasm, nucleus, and chloroplasts.
Procedures
Part A – The Cell Wall
In a cork cell the cell wall is easily visible. However, the cell is no longer living. The cell wall remains as the only
evidence of once living materials. The cell wall is one of the cell parts that are found in all plant cells, but not in
animal cells.
1) Use a razor blade to slice off a very thin section of cork. The slice should be made from the side of the
cork, not its top or bottom. Caution – to avoid cutting yourself, slice away from your fingers, not toward
them.
2) Prepare a wet mount of your cork slice.
3) Examine the cork under low power. It may be easiest to find individual cork cells by looking at the outer
edges of your cork slice.
4) Examine the cork under medium power. In the space below draw several cork cells as they appear under
medium magnification. On your drawing label the cell wall.
Object: _____________________
Magnification: _______________
Answer the following questions:
1) Describe the appearance of these cork cells.
2) Are these cells alive?
3) Are the cells filled with living material or are they empty?
4) Are cork cells part of a producer or consumer?
5) What cellular structure gives these cells their boxy shape?
6) Use your textbook to determine
a. Who is the scientist credited with first seeing these structures?
b. What is the name of the chemical that makes up the cell wall?
Part B – Cell membrane, nucleus and cytoplasm
Human cheek cells are excellent for examining cell membranes and cytoplasm.
1) Place a drop of methylene blue on a slide.
2) Gently scrape the inside of your cheek with the blunt end of a toothpick (up front)
3) Dip the toothpick into the methylene blue on your slide and swirl it once or twice.
4) Add a coverslip and then examine the slide under low power. Then examine it under high power.
5) Look for cells that are separated from one another rather than those found in clumps. In the space below
draw what you see under high power.
6) On your drawing label the following - cell membrane, nucleus, and cytoplasm
Object: __________________
Magnification: ____________
Answer the following questions:
1) Describe the shape of the cheek cells.
2) Do the cheek cells have cell walls? Explain.
3) Do the cheek cells have cell membranes? Explain
4) Why might the shape of cheek cells be less regular than the shape of cork cells?
5) What is the dark spot you saw inside your cheek cells?
6) Are cheek cells alive? Explain
7) Do cheek cells come from producers or consumers?
8) Do you have evidence that living things (or once living things) are composed of basic units called cells?
Explain your answer.
9) Referring to your notes or textbook – Who is the scientist credited with concluding that animals are made
up of living cells?
Part C - Comparison of plant and animal cells
You will look at two new cells under the microscope. Determine which of the following organelles can be seen –
cell membrane, cell wall, cytoplasm, nucleus, and chloroplast. Complete the following chart as you look at each
slide.
Living or
dead?
Frog blood
cells
Elodea
(plant)
Cellular
General
organization? shape of the
(yes or no)
cell?
From a
producer or
a consumer?
Cell wall
present?
(yes or no?)
List
additional
organelles
present
Frog blood cells
1) obtain a prepared frog blood slide (from up front)
2) observe the cells under low and high power
3) make a drawing of the blood cells in space provided below
4) based on your observations – complete the ‘blood cells’ portion of the data table
Object: ________________
Magnification: __________
Elodea
1) Obtain an Elodea leaf (from up front)and prepare a wet mount slide of it
2) Using low power, position your slide so that you are looking at the edge of the leaflet. Locate green,
oblong cells. The small green organelles that you see are chloroplasts. You may observe movement of the
chloroplasts within the cell.
3) Observe these cells under high power and make a drawing of them in the space provided below
4) Based on your observations – complete the ‘elodea’ portion of the data table
Object: __________________
Magnification: ____________
Answer the following questions:
1) What color are chloroplasts?
2) What is the function of chloroplasts?
3) Using the data table as a reference – answer the following questions.
a. What cell parts are found only in the cells of producers?
b. Name 2 differences between plant and animal cells (producer and consumer)
Part D: Cell nucleus and nucleolus
1) Remove the thin transparent layer of cells from the inside of a section of onion. Lay this thin layer on a
slide. Make sure to unfold any overlapped portion of the cell layer so that it lays perfectly flat on the slide.
2) Add a drop or two of iodine stain to the onion section and then cover with a coverslip.
3) Observe the onion cells under low, medium and then high power of your microscope.
4) Find cells with a good, visible nucleus. Examine the nucleus carefully and locate the tiny structures within
the nucleus. These structures are the nucleoli.
5) In the space provided below make a drawing of two cells under high power.
6) Label the following on your drawing – cell wall, nucleus, nucleoli, and nuclear membrane.
Object: _________________
Magnification: ___________
Answer the following questions:
1) What is the main function of the cell nucleus?
2) What is the main function of the nuclear membrane?
3) Why were the cells stained with iodine?
4) What is the main function of the nucleoli (plural of nucleolus)?
Analysis – complete the diagrams below as instructed
1) Complete figure 1. It shows a “typical” plant cell. Label the parts listed below.
cell wall
cell membrane
nucleus
cytoplasm
chloroplasts
nucleolus
Figure 1 – plant cell
2) Use your text to determine where the following plant cell parts are located. Draw and label each of these
parts onto Figure 1 as they would appear under an electron microscope.
vacuole
mitochondria golgi bodies
ribosomes
lysosome
endoplasmic reticulum
3) Complete figure 2. It shows a “typical” animal cell. Label the parts listed below.
cell membrane
nucleus
nucleolus
cytoplasm
Figure 2 – animal cell
4) Use you text to determine where the following animal cell parts are located. Draw and label each of these
parts onto Figure 2 as they would appear under an electron microscope.
mitochondria centrioles
golgi bodies
ribosomes
lysosome
endoplasmic reticulum