Logical Chain: The Evolutionary Advantage of Double Fertilization

Question: Why did angiosperms evolve double fertilization?

Step 1 — Problem to solve: A growing embryo needs nutrition. In gymnosperms, the nutritive tissue (endosperm) is pre-formed BEFORE fertilization, wasting energy when fertilization does not occur (unfertilized ovules still have nutritive tissue).

Step 2 — Angiosperm solution: Angiosperms evolved "conditional endosperm" — the endosperm forms ONLY if fertilization occurs (triple fusion must happen). This means nutritive tissue is NOT wasted.

Step 3 — Mechanism: Double fertilization ensures:

• Syngamy → embryo (the next generation)
• Triple fusion → endosperm (food supply, conditional on fertilization) Both happen simultaneously, so a seed develops only when it has BOTH an embryo AND food for it.

Step 4 — Consequence: This is more efficient than gymnosperms:

• No wasted endosperm in unfertilized ovules
• Seed quality is higher (every seed has a guaranteed food supply)
• Better germination success

Step 5 — NEET Application: "Double fertilization is an adaptation that couples embryo formation with endosperm formation, ensuring resources are allocated only to developing seeds."

Why This Matters for NEET

Higher-order questions may ask about the "significance" or "advantage" of double fertilization. The answer is: it couples embryo development with endosperm formation, ensuring nutritional support is produced only when fertilization actually occurs.