The endosperm of an angiosperm differs from that of a gymnosperm in that it :

Options

A. contains glycogen rather than starch
B. contains less fat
C. does not form until fertilization takes place
D. only lasts a few days

Explanation

To answer the question "The endosperm of an angiosperm differs from that of a gymnosperm in that it:", we can follow these steps:

### Step 1: Understand the Definitions
- **Angiosperms** are flowering plants that produce seeds enclosed within a fruit.
- **Gymnosperms** are non-flowering plants that produce naked seeds, meaning their seeds are not enclosed within a fruit.

### Step 2: Identify the Role of Endosperm
- **Endosperm** is a tissue that provides nourishment to the developing embryo within the seed. It plays a crucial role in seed development.

### Step 3: Compare Endosperm in Angiosperms and Gymnosperms
- In **angiosperms**, the endosperm is formed **after fertilization** and is typically **triploid (3N)** due to a process called double fertilization.
- In **gymnosperms**, the endosperm is formed **before fertilization** and is usually **haploid (N)**.

### Step 4: Analyze the Options Given
The options provided are:
A. Contains glycogen rather than starch
B. Contains less fat
C. Does not form until fertilization takes place
D. Only lasts a few days

From our understanding:
- Option A is incorrect as the type of storage material varies but is not the primary difference.
- Option B is not a defining characteristic.
- Option C is correct because the endosperm in angiosperms does not form until after fertilization.
- Option D is incorrect as the lifespan of the endosperm is not a defining factor in this context.

### Conclusion
The correct answer is **C: Does not form until fertilization takes place**.

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