Describe any two modes by which apomictic seeds and be produced.

Explanation

**Step-by-Step Solution:**

1. **Understanding Apomixis**: Apomixis is a form of asexual reproduction that results in the formation of seeds without fertilization. This process mimics sexual reproduction but does not involve the fusion of male and female gametes.

2. **Mode 1: Diploid Egg Formation**: In some flowering plants, the egg cell (female gamete) is diploid instead of haploid. This means that it does not require fertilization to develop into an embryo. The diploid egg cell can directly develop into an embryo, leading to the formation of a seed without the need for male gamete involvement.

3. **Mode 2: Nucellar Embryony**: Another method of apomictic seed formation occurs in certain plants, such as some varieties of citrus and mango. In this case, cells from the nucellus (the tissue surrounding the embryo sac) undergo division and then protrude into the embryo sac. These nucellar cells then develop into an embryo, resulting in seed formation without fertilization.

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