Fruits And Seed Formation

fruits and seed formation by Delta publications

Key Notes :

Introduction to Fruits and Seed Formation

  • Fruits are mature, ripened ovaries of flowers.
  • They enclose and protect the seeds during development.
  • Seed formation is a result of the fertilization process in flowering plants.

Process of Fruit and Seed Formation

Pollination

Transfer of pollen grains from the male anther to the female stigma.

Types:

  • Self-pollination (same flower/plant).
  • Cross-pollination (different plants).

Fertilization

  • Fusion of male and female gametes (in the ovule).
  • Results in the formation of a zygote.

Development

  • Zygote develops into an embryo (seed).
  • Ovule becomes the seed, and the ovary becomes the fruit.

Structure of a Seed

Seed Coat: Protects the seed.

Embryo: Contains:

  • Plumule (develops into shoot).
  • Radicle (develops into root).

Cotyledons: Store food for the developing embryo.

Types of Fruits

Simple Fruits

  • Formed from a single ovary.
  • Example: Mango, Pea.

Aggregate Fruits

  • Formed from multiple ovaries of a single flower.
  • Example: Strawberry, Raspberry.

Multiple Fruits

  • Formed from ovaries of multiple flowers.
  • Example: Pineapple, Jackfruit.

Importance of Fruits and Seeds

  • Protection of Seeds: Fruits protect seeds from damage and desiccation.
  • Dispersal of Seeds: Help in spreading seeds through animals, wind, and water.
  • Food Source: Many fruits and seeds are edible and provide nutrients.

Seed Dispersal

  1. By Wind: Seeds like dandelion have lightweight structures.
  2. By Water: Coconut seeds float.
  3. By Animals: Juicy fruits attract animals; seeds are dispersed after consumption.
  4. By Explosion: Seeds are forcefully ejected (e.g., Pea pods).

Germination of Seeds

The process where a seed develops into a new plant.

Requires:

  • Water (activates enzymes).
  • Oxygen (energy production).
  • Optimal Temperature (enzymatic activity).

Let’s practice!