Cell Structure and Function

Barbara J. Baker               Doolittle West Primary School
                               521 East 35th Street
                               Chicago IL  60616
                               (773) 535-1050

Objectives:

Discuss scientific advances brought about by the Mars Surveyor Space Program 
   which impact on daily life, especially any animal and plant cell movements.
Identify laboratory apparatus like microscopes, slides and coverslips; use the 
   microscopes to view cells and organisms.
Learn vocabulary pertaining to cells. 
Draw and color what is seen under the microscope.
This lesson could be used for grades 3rd-5th. 
 
Vocabulary:  cell membrane         endoplasmic reticulum
             cytoplasm             golgi bodies
             nucleus               Paramecium
             mitochondria          Euglena
             lysosomes             Ameoba

Materials Needed:

Newspaper articles about the Pathfinder landing on Mars.  Microscopes, slides 
and coverslips, flowers and onions, posters of enlarged animal and plant cells, 
plant and animal cell component labels, cartoon posters of 3 types of cells and 
various strands of human hair, Elodea specimen and pond water (Elodea is a 
commercially available alga).  This is a list of materials for each student in 
the class with the exception of microscopes: posters of enlarged animal and 
plant cells and cartoon posters of Paramecium, Euglena, and Amoeba; lemon 
gelatin dessert mix; l pint (125-ml) resealable plastic bag; quart bowl; large 
grape. 
 
Strategies:

1.  Classroom discussions about the Mars Space Program.
2.  Articles on the Mars space program read aloud in class followed by role 
    playing.
3.  Locating articles that discuss possible fossils of cells found on Mars.
4.  Using a slide to observe Elodea specimen under the microscope.
5.  Observing what type of movement the specimen is making.
6.  Flagellar, ciliate, and amoeboid motion will be looked for under 
    the microscope.
7.  Predict the condition of hair by observing a strand under the microscope.
8.  Determine which end of the hair strand was attached to a live cell.
9.  Gather some pollen from a flower, place it on a slide, and observe the 
    pollen under the microscope.
10. Draw the cells you see from items 4, 8, and 9 above on a sheet of paper; 
    color the cells.
11. Observe the same slide 30 minutes later or the next day to see what changes 
    occurred.
12. A cooperative team will use a small picture of the animal cell that is 
    labeled with the parts of the cell to identify the same parts on the 
    enlarged poster of the animal cell that is not labeled.
13. The other cooperative group will place and paste the parts of the plant cell 
    on the enlarged poster of the plant cell using the small labeled picture of 
    the plant cell as a guide.
14. Each student will make a World-Class Cell Model.
    a. Have an adult helper mix the ingredients for the gelatin dessert 
       according to the instructions on the box.
    b. Allow the gelatin to cool to room temperature. 
    c. Pour the gelatin into the resealable bag, seal the bag, and place it in 
       the bowl.
    d. Set the bowl and bag in the refrigerator and chill until the gelatin is 
       firm (about 3 to 4 hours).
    e. Remove the gelatin from the refrigerator and open the bag.
    f. Using your finger, insert the grape into the center of the gelatin
    g. Reseal the bag.
    h. Place the bag of gelatin on a flat surface such as the kitchen counter.
       Observe its shape.
    i. Hold the bag over the bowl as you gently squeeze it (the bowl is used 
       in the event that you squeeze too hard and the bag opens).  Observe the 
       shape of the bag as you squeeze
15. Thin layers of onion cell skin will be prepared, placed on slides, covered 
    with coverslips, and observed under the microscope. 
16. Write a rap or poem concerning the structure and/or movement of cells.

Performance Assessment:

1.  Students will share the articles on Mars with role playing.
2.  Students will take a multiple choice quiz on the hierarchy of the 
    organizational levels of living things.  Below is an example of testing 
    students on knowing the difference between cell, tissue, organ, system and 
    body.  You may rewrite it leaving cell off each item. 
  
    Directions:  On the quiz below one list would be in a correct order if
    you were to write organ in the blank.  Which list is that?

    a. cell, tissue, system, body, ______
    b. cell, tissue, ______, system, body
    c. ______, cell, tissue, system, body
    d. cell, ______, tissue, body, system

3.  The nature of movements of cells in the human body will be discussed.
4.  The labeled posters of plant and animal cells will be read aloud.
5.  A simple model of a cell with 3 parts will be made.
    a. Each student will understand that the plastic bag represents the membrane 
       of the model cell.   
    b. Each student will properly name the pale color of the gelatin dessert as 
       the grayish jellylike material cytoplasm, that fills the cell.
    c. Floating in the gelatin is a grape the represents the nucleus.