Final answer:
The sepals are collectively called the calyx and they protect the flower before it opens.
Step-by-step explanation:
The sepals are collectively called the calyx. They are the green structures that protect the flower before it opens. The calyx is made up of the whorl of sepals. Sepals are usually photosynthetic organs, although there are exceptions, and they form the outermost whorl of a flower.
The sepals are the leafy structures at the base of a flower that protect the flower bud, and collectively, they are known as the calyx.
In flower structure, the sepals are the green, leafy parts at the base of the flower. They serve to protect the unopened floral bud. Collectively, the sepals are known as the calyx, which is typically green. Therefore, the answer to the question 'The ________ are collectively called the calyx' is a) Sepals.