Problem 99 - Objective Biology for NEET

Question

Following are the non-endospermic seed except (a) Bean (b) Gram (c) Pea (d) Castor

Step-by-Step Solution

Answer

Out of the given options, (d) Castor is an endospermic seed while the rest are non-endospermic.

Step 1: Identify Non-endospermic seeds

Let's go through the list: (a) Bean - is a non-endospermic seed as the food storage is in the cotyledon; (b) Gram - this too is a non-endospermic seed with the food storage being in the cotyledon; (c) Pea - it is a non-endospermic seed as well as the storage is in the cotyledon; (d) Castor - unlike the rest, Castor is an endospermic seed where food storage is in the endosperm.

Key Concepts

Seed Types

In the world of botany, understanding different types of seeds is essential for studying plant biology. Seeds can be categorized based on the presence or absence of endosperm at maturity. In simple terms, seeds are the plant's way of reproducing and ensuring the survival of the species.

Cotyledons in Seed Storage

Cotyledons are the primary leaves in the embryo of a seed. In the case of non-endospermic seeds, also known as exalbuminous seeds, cotyledons are responsible for storing food that will be consumed by the seedling after germination.

During the development of non-endospermic seeds, the endosperm is absorbed by the cotyledons, which become filled with nutrients such as starch, proteins, and fats.

• The pea, for example, has large and fleshy cotyledons that contain all the reserves needed for the plant to grow until it's capable of photosynthesis.
• Consequently, when the seed germinates, the cotyledons may either remain underground, known as hypogeal germination, or rise above the ground, which is called epigeal germination.

For students learning about the role of cotyledons in seed storage, it's essential to grasp that these structures are crucial for the initial growth phase of the plant.

Endospermic vs Non-Endospermic Seeds

In the botanical world, understanding the difference between endospermic and non-endospermic seeds is crucial.

• Endospermic seeds, such as castor, maintain their endosperm as a separate tissue through which nutrition is provided to the developing seedling.
• On the other hand, as seen in options (a) Bean, (b) Gram, and (c) Pea, non-endospermic seeds have cotyledons that have taken over the role of food storage, absorbing the endosperm during the seed's development.

When studying this concept, focusing on the location of food reserve storage within the seed and its role in germination is important. The exercise presented helps in identifying which seeds belong to each category based on the food storage method, thereby enhancing the botanical understanding of seed types.