Perisperm differs from endosperm in

Options

A. Being a diploid tissue
B. Its formation by fusion of secondary nucleus with several sperms
C. Being a haploid tissue
D. Having no reserve food

Answer

To answer the question "Perisperm differs from endosperm in," we need to understand the definitions and functions of both perisperm and endosperm in flowering plants. Here’s a step-by-step breakdown of the differences:

### Step 1: Define Endosperm
- **Endosperm** is a tissue produced in the seeds of flowering plants (angiosperms) that provides nutrition to the developing embryo. It is formed after fertilization from the triploid cell resulting from the fusion of one sperm cell with two polar nuclei in the embryo sac.

### Step 2: Define Perisperm
- **Perisperm** is a tissue that surrounds the embryo in some seeds and is derived from the nucellus (the central part of the ovule). It is formed before fertilization and serves as a food reserve for the developing seed.

### Step 3: Compare Their Formation
- **Formation**:
- Endosperm is formed after fertilization and is triploid (3n).
- Perisperm is formed from the nucellus and is diploid (2n).

### Step 4: Compare Their Functions
- **Function**:
- Endosperm primarily serves as a food source for the embryo during seed development and germination.
- Perisperm also provides nutrition but is often less significant than endosperm in terms of the nutritional support it offers.

### Step 5: Summarize the Differences
- **Key Differences**:
- **Origin**: Endosperm is formed after fertilization; perisperm is derived from the nucellus before fertilization.
- **Ploidy Level**: Endosperm is triploid (3n); perisperm is diploid (2n).
- **Nutritional Role**: Endosperm is the main source of nutrition for the embryo; perisperm serves a supportive role.

### Conclusion
In summary, perisperm differs from endosperm in terms of origin (pre-fertilization vs. post-fertilization), ploidy level (diploid vs. triploid), and their roles in seed nutrition.

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