Are Modified Leaves Which Enclose and Protect?

The buds of many woody plants are protected by a covering of modified leaves called bud scales. The bud scales enclose and protect the embyonic cells of the apical meristem which can remain dormant for extended periods.

Are the modified leaves which enclose and protect the other parts of a flower when it is still a bud?

Answer: When a flower is a bud, it is surrounded by sepals, which in many cases are green, as in this example. They protect the flower bud and are behind/underneath the petals when the flower opens. Together, all of the sepals are called a calyx.

What are the modified leaves that protect the ovule called?

In the center of a typical flower are the carpels, modified leaves which enclose the ovules. These are often fused to form a single pistil in the center of the flower.