The Parts of A Perfect Flower

Guinevere Miller               Englewood High School
                               6201 S. Stewart Ave.
                               Chicago, Ill. 60621
                               (312) 723-1710 Ext. 643

Objectives: 

Upon completion of this lab activity, the student will be able to
  (1) identify each flower part.
  (2) explain the role of each flower part.

Materials needed:

(1) Gladiola/lilies               (7) construction paper
(2) razor blades                  (8) toothpicks
(3) glass slides                  (9) two dissecting microscopes
(4) paper towels                 (10) overhead projector
(5) markers                      (11) prepared lab sheets
(6) glue or scotch tape          (12) prepared transparency 

Strategy:

 (1) The students should study the model of the flower and determine whether the 
     flower is complete or incomplete, perfect or imperfect.  The students 
     should now focus their attention on the diagram of the flower and label all 
     flower structures. 
 (2) The students should carefully dissect the flower, answer questions and do 
     the required drawings.
 (3) As the students dissect their flower, use the overhead projector to show
     each flower part.
 (4) Have each student or each group of students tape or glue and label each 
     flower part on construction paper. 
 (5) Have the students observe pollen grains and ovules under the dissecting 
     microscope. 

Student Activities:

Part A: The Sepals and Petals.  Carefully examine your specimen.
          Trace the stem to the base of the flower.

 (1) Does the stem appear wider as it nears the base of the flower?
 (2) What is the thick part of the stem called?
 (3) What is its function?
 (4) Do you see green leaves surrounding the bottom of the flower?
 (5) What are they called?
 (6) How many can you count on your specimen?
 (7) What is their function?
    
     Observe the colored petals of your flower
   
 (8) How many are present?
 (9) What advantage to the flower are colored petals?

Part B: The Pistil and Stamen.  Carefully remove enough sepals and petals from 
        your flower so that you can observe the inner parts.  Do you see a large 
        stalklike part in the center of the flower?  This part is called the 
        pistil.  It is divided into three areas.  The large, bottom part is 
        called the ovary, the middle area is called the style and the top part 
        is called the stigma. 

(10) Draw and label the three areas of the pistil: stigma, style and ovary.
                 
     Surrounding the pistil are several upright stalks.

(11) What are these called?
     If you observe carefully, you can see structures attached to the tops of 
     the stalks. 
(12) What are these called?
(13) What do they produce?

Part C: The Ovary.  Carefully remove the pistil from your flower.
        With your razor blade, cut across the ovary.

(14) What do you see inside the ovary?
(15) What is the function of the ovary?  
(16) What is the biological function of the flower?
(17) Draw the stamen and label the anther and the filament.
(18) Name the three ways that pollen may be carried.
(19) What is a perfect flower?
(20) What is a complete flower?