Seeds

Definition

Seeds are the reproductive structures produced by flowering plants and gymnosperms, containing the embryo and stored nutrients that enable the plant to grow into a new organism. They play a crucial role in the plant life cycle, allowing for reproduction, dispersal, and genetic diversity. Seeds are protected by a seed coat and can remain dormant until environmental conditions are favorable for germination.

5 Must Know Facts For Your Next Test

1. Seeds can remain dormant for extended periods, sometimes years, until conditions such as moisture, temperature, and light are suitable for germination.
2. The structure of seeds varies significantly among different plant species, with some having adaptations for wind or water dispersal, while others rely on animals.
3. Seeds provide a food source for various organisms, playing an essential role in ecosystems by supporting biodiversity and food webs.
4. Angiosperms produce seeds within fruits, which aid in seed dispersal mechanisms, while gymnosperms typically produce naked seeds on cones.
5. The genetic material within seeds contributes to the variability and adaptation of plant populations over time, promoting evolutionary processes.

Review Questions

• How do seeds contribute to the reproductive success of plants?
  • Seeds enhance reproductive success by allowing plants to reproduce sexually and promote genetic diversity through the combination of parental traits. They protect the developing embryo and provide stored nutrients that support growth during germination. Additionally, seeds can be dispersed over long distances by wind, water, or animals, facilitating colonization of new habitats and reducing competition among offspring.
• Discuss the role of seed structure in determining its method of dispersal and germination requirements.
  • The structure of seeds influences how they are dispersed and their requirements for germination. For example, seeds with smooth surfaces may be adapted for wind dispersal, while those with hooks or sticky surfaces may attach to animal fur for transport. Additionally, some seeds have hard coats that require specific environmental conditions or physical abrasion to break dormancy and allow water absorption necessary for germination.
• Evaluate the ecological implications of seed dormancy and dispersal mechanisms in plant populations and ecosystems.
  • Seed dormancy and dispersal mechanisms have significant ecological implications for plant populations and ecosystems. Dormancy allows seeds to survive unfavorable conditions and germinate when environments become suitable, promoting resilience in fluctuating climates. Effective dispersal strategies enhance genetic diversity by spreading seeds across varied habitats, which can lead to adaptation in changing environments. This dynamic interaction supports ecosystem stability, as diverse plant communities are better equipped to respond to disturbances and support various animal species.

Related terms

Germination: The process by which a seed develops into a new plant, starting with the emergence of the radicle, or root, from the seed.

Cotyledon: The first leaf or leaves that appear from a germinating seed, providing essential nutrients to the developing plant before true leaves form.

Pollination: The transfer of pollen from the male structures to the female structures of flowers, enabling fertilization and the formation of seeds.