Geitonogamy does not occur in

Options

A. Dioecious plant
B. Monoecious plant
C. Both of the above
D. It occurs in all the plants

Answer

To solve the question "Geitonogamy does not occur in," we need to understand the definitions and characteristics of the types of plants mentioned in the options. Let's break it down step by step.

### Step 1: Understand Geitonogamy
Geitonogamy is a type of pollination where pollen grains from the anther of one flower are transferred to the stigma of another flower on the same plant. This means that for geitonogamy to occur, the plant must have multiple flowers.

**Hint:** Remember that geitonogamy involves two flowers on the same plant.

### Step 2: Differentiate Between Dioecious and Monoecious Plants
- **Dioecious Plants:** These are unisexual plants where individual plants are either male or female. Male plants produce only staminate flowers (with stamens), and female plants produce only pistillate flowers (with pistils). Since there are no male and female flowers on the same plant, geitonogamy cannot occur.

- **Monoecious Plants:** These plants have both male and female flowers on the same individual. This allows for the possibility of geitonogamy, as pollen can be transferred from the male flower to the female flower on the same plant.

**Hint:** Identify whether the plants have both male and female flowers (monoecious) or only one sex (dioecious).

### Step 3: Analyze the Options
1. **Dioecious Plant:** As explained, geitonogamy does not occur here because there are no male and female flowers on the same plant.
2. **Monoecious Plant:** Geitonogamy can occur because both male and female flowers are present on the same plant.
3. **Both of the Above:** This option is incorrect because geitonogamy does not occur only in dioecious plants.
4. **It Occurs in All Plants:** This option is also incorrect, as geitonogamy does not occur in dioecious plants.

**Hint:** Eliminate options based on the definitions of dioecious and monoecious plants.

### Step 4: Conclusion
Based on the analysis, the correct answer is that geitonogamy does not occur in **dioecious plants**.

**Final Answer:** Dioecious plants.