BOTANY LABORATORY PRACTICAL (PLANT ANATOMY AND MORPHOLOGY) - O.A. SHEVCHUK - 2014

THE FLOWER

TOPIC 6. STRUCTURE OF THE ANTHER, OVARY, AND OVULE

General notes. The anther serves as the carrier of male hereditary information. Within the anther locules, a tetrad of microspores is formed from each Cell of the sporogenous tissue via Meiosis. These microspores develop into pollen grains, which represent the male gametophyte of a flowering plant. As an organ of spore production, the anther possesses a complex Structure. When examining it, pay close attention to the structural features and Functions of its individual parts.

The Ovary also features a complex Cytology/cytology/67.html">Development and Structure. Its locules contain ovules, where tetrads of megaspores are formed from the archesporial cell through meiosis. One of these megaspores develops into the embryo sac (female gametophyte).

During double Fertilization, the diploid zygote—formed by the fusion of the egg cell and a sperm cell—develops into the embryo, while the triploid zygote, resulting from the fusion of the diploid central cell and a sperm cell, forms the triploid endosperm. As a consequence, a seed develops from the ovule, and a fruit develops from the ovary.

Objective: to study the morpho-Water/140.html">Anatomical Structure of stamens (androecium); to examine the morpho-anatomical STRUCTURE OF THE pistil (gynoecium), as well as the types of Ovaries and gynoecia.

Materials and equipment: live and fixed floral material, flower models, charts, permanent Microscope slides (transverse section of an anther, transverse section of an ovary), and laboratory equipment.

Tasks

1. Study The structure of the anther and its component parts.

2. Examine the Structural Features of the ovary and ovule.

3. Study the structure of the embryo sac.

4. Examine various shapes of stamens.

5. Examine various types of androecium.

Label the drawings and draw Conclusions.

Conclusion

Self-control questions

1. WHAT IS A flower, and what parts does it consist of?

2. What is referred to as the androecium of a flower?

3. Provide Examples of flowers with polypetalous and sympetalous stamens. Characterize them.

4. What parts does a stamen consist of?

5. What types of pollen grains do you know? Describe them.

6. What is the gynoecium?

7. How does a unicarpellate gynoecium differ from a syncarpellate one?

8. What are the types of coenocarpous gynoecium?

9. What is the difference between superior, inferior, and half-inferior ovaries?

10. What is the structure of the pistil?

11. What are the types of placentation (ovule arrangement)?

12. What is the structure of the ovule?

13. What is the embryo sac? How is it formed and what Cells does it consist of?