Differentiate between major structural changes in the human ovary during the follicular and luteal phase of the menstrual cycle.

Explanation

### Step-by-Step Solution

1. **Understanding the Phases**: The menstrual cycle consists of two main phases concerning the ovary: the follicular phase and the luteal phase. Each phase is characterized by distinct structural changes in the ovary.

2. **Follicular Phase Changes**:
- During the follicular phase, the primary follicles in the ovary undergo maturation.
- The primary follicles grow and develop into fully mature Graafian follicles. This process involves several stages of follicular development, including the formation of secondary and tertiary follicles.

...