Differentiate the following:
Fertilisation and double fertilisation

Explanation

### Step-by-Step Solution:

1. **Definition of Fertilization**:
- Fertilization is the biological process where one male gamete (sperm) fuses with one female gamete (egg) to form a diploid zygote. This process is fundamental in sexual reproduction and occurs in various organisms.

2. **Definition of Double Fertilization**:
- Double fertilization is a unique process that occurs in angiosperms (flowering plants), where one male gamete fuses with the egg to form a diploid zygote, while the second male gamete fuses with two polar nuclei to form a triploid primary endosperm.

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