Sex organs of Riccia are

Options

A. Projecting
B. Embedded
C. Occur in receptacles
D. Borne laterally.

Answer

To answer the question about the sex organs of Riccia, we can break down the information step by step:

### Step-by-Step Solution:

1. **Identify the Organism**: Riccia is a type of liverwort, which belongs to the group of non-vascular plants known as bryophytes.

2. **Understand the Structure**: The body of Riccia is thalloid, meaning it does not have distinct stems, roots, or leaves. This thallus structure is important in understanding where the reproductive organs are located.

3. **Reproductive Process**: In Riccia, sexual reproduction occurs through the fusion of male and female gametes.

4. **Male Gamete Formation**: The male gametes are produced in structures called antheridia. These antheridia are located dorsally within a chamber known as the antheridium chamber.

5. **Female Gamete Formation**: The female gametes are produced in structures called archegonia, which are also found dorsally.

6. **Location of Sex Organs**: Both the antheridia and archegonia are embedded within the thallus of the Riccia plant. This means they are not projecting outwards or located in separate receptacles; instead, they are integrated into the plant body.

7. **Conclusion**: Based on the above information, the correct answer to the question "Sex organs of Riccia are" is that they are **embedded**.

### Final Answer:
The sex organs of Riccia are **embedded**.

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