Let me explain the structure of a paddy seed (rice grain) which is actually a fruit called a caryopsis. In this type of fruit, the seed coat is fused with the fruit wall.

Key Labeled Parts:

1. Hull (Husk): This is the outermost protective covering of the paddy seed. It is made up of two structures: the lemma (larger) and the palea (smaller). The hull is inedible and must be removed to get brown rice.

2. Endosperm: This is the largest part of the seed and is the starchy food storage tissue. It provides nutrition to the developing embryo (germ) during germination. The endosperm is what we primarily eat as white rice.

Other Important Parts (for your knowledge):

Embryo (Germ): The baby plant, which can develop into a new rice plant.
Aleurone Layer: A protein-rich layer that surrounds the endosperm.
Scutellum: The cotyledon (seed leaf) of the grass family, which absorbs food from the endosperm for the growing embryo.

Related Topics & Formulae:

Topic: Seed Structure
A seed is a mature ovule that contains an embryo and stored food, enclosed in a protective seed coat. It is a key unit in the sexual reproduction of plants.

Topic: Parts of a Seed
The three main parts of a typical seed are: 1. Seed Coat: Protective outer covering. 2. Endosperm: Nutritive tissue. 3. Embryo: The young plant.

Topic: Types of Seeds
Seeds are classified based on the presence or absence of endosperm: - Endospermic seeds (Albuminous): Endosperm is not completely used up by the embryo (e.g., wheat, rice, castor). - Non-endospermic seeds (Exalbuminous): Endosperm is completely consumed during development (e.g., gram, pea, groundnut).