Synergid Cells

Definition

Synergid cells are specialized cells found in the embryo sac of flowering plants, playing a crucial role in the fertilization process. They are located at the micropylar end of the embryo sac and are involved in guiding the pollen tube toward the egg cell. The synergids also secrete signals that facilitate successful fertilization and help nourish the developing embryo.

5 Must Know Facts For Your Next Test

1. Synergid cells have unique structures, including filiform apparatuses that aid in the attraction and guidance of the pollen tube.
2. These cells undergo programmed cell death after successful fertilization, ensuring that resources are directed to support the developing embryo.
3. Synergid cells can produce signaling molecules that influence pollen tube growth and direct it toward the egg cell.
4. There are typically two synergid cells present in each embryo sac, working together to facilitate fertilization.
5. The interaction between synergid cells and the pollen tube is crucial for ensuring successful double fertilization, which leads to both an embryo and endosperm formation.

Review Questions

• How do synergid cells contribute to the process of fertilization in flowering plants?
  • Synergid cells play an essential role in the fertilization process by guiding the pollen tube towards the egg cell. Located at the micropylar end of the embryo sac, they secrete signaling molecules that attract and direct the pollen tube. This interaction is critical for ensuring that sperm cells can reach and successfully fertilize the egg cell, leading to seed development.
• What mechanisms do synergid cells use to interact with the pollen tube, and why are these interactions significant?
  • Synergid cells utilize specialized structures called filiform apparatuses to interact with the pollen tube. These structures create a conducive environment for the pollen tube's growth and navigation toward the egg cell. The interactions between synergids and the pollen tube are significant because they ensure precise targeting of fertilization, which is essential for successful reproduction in flowering plants.
• Evaluate the importance of synergid cells in plant reproductive success and how their functions might influence plant diversity.
  • Synergid cells are vital for reproductive success as they facilitate precise fertilization, ensuring that sperm reaches the egg cell effectively. Their role in directing pollen tubes also impacts genetic diversity within plant populations by promoting cross-fertilization. By aiding in successful fertilization events, synergid cells contribute to a higher rate of seed production and genetic variation, which is crucial for adaptation and resilience of plant species in changing environments.

Related terms

Embryo Sac: The female gametophyte in flowering plants, containing the egg cell, synergids, and polar nuclei, which will develop into seeds after fertilization.

Pollen Tube: A tube that forms from a pollen grain after it lands on a compatible stigma, allowing sperm cells to travel down to the ovule for fertilization.

Ovary:

The part of the flower that contains the ovules and develops into fruit after fertilization, playing a key role in reproductive development.