1. Introduction to Fruits

  1. A fruit is a matured and ripened ovary that contains seeds.
  2. It develops after fertilization, although some fruits form without fertilization (called parthenocarpic fruits).
  3. The primary function of fruits is to protect seeds and aid in their dispersal.

2. Structure of a Fruit

  1. A fruit consists of two main parts: the pericarp (fruit wall) and the seeds.
  2. The pericarp has three layers:
    • Epicarp: The outermost layer, often forming the skin of the fruit.
    • Mesocarp: The middle, fleshy layer (e.g., mango).
    • Endocarp: The innermost layer, protecting the seeds (e.g., hard shell in coconut).

3. Classification of Fruits

  1. Fruits are classified into three main types:

4. Simple Fruits

  1. Develop from a single ovary of a single flower.
  2. They can be further classified into fleshy and dry fruits.

a) Fleshy Fruits

  1. Drupe: Has a single seed with a hard endocarp (e.g., mango, coconut).
  2. Berry: Entire fruit is fleshy (e.g., tomato, grape).
  3. Pome: Develops from an inferior ovary, with fleshy receptacle (e.g., apple, pear).

b) Dry Fruits

  1. Fruits where the pericarp is dry at maturity.
  2. They are further classified into:
    • Dehiscent Fruits: Split open when mature to release seeds (e.g., pea, bean, cotton).
    • Indehiscent Fruits: Do not split open at maturity (e.g., maize, sunflower).

5. Aggregate Fruits

  1. Develop from a single flower with multiple ovaries.
  2. Each ovary develops into a small fruit called a fruitlet, forming a cluster.
  3. Examples: Strawberry, raspberry, custard apple.

6. Multiple Fruits (Composite Fruits)

  1. Develop from an inflorescence (group of flowers).
  2. Each flower contributes to a part of the final fruit.
  3. Examples:
    • Sorosis: Develops from catkin or spike inflorescence (e.g., pineapple, jackfruit).
    • Syconus: Develops from a hypanthodium inflorescence (e.g., fig).

7. Introduction to Seeds

  1. A seed is a fertilized and mature ovule that gives rise to a new plant.
  2. It consists of three parts:
    • Seed Coat: The protective outer covering.
    • Embryo: The young plant consisting of a radicle (root) and plumule (shoot).
    • Endosperm: Provides nutrients to the developing seed.

8. Classification of Seeds

  1. Monocot Seeds: Have one cotyledon (e.g., maize, wheat).
  2. Dicot Seeds: Have two cotyledons (e.g., bean, pea).

9. Importance of Fruits and Seeds

  1. Fruits protect the seeds and help in seed dispersal.
  2. Many fruits and seeds are important in human nutrition.
  3. Seed banks help preserve plant biodiversity.

10. Conclusion

  1. Fruits are an essential part of plant reproduction and aid in seed dispersal.
  2. Different types of fruits exist based on their developmental origin.
  3. Seeds play a crucial role in plant propagation and agriculture.

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