Question

The chloroplast internal membrane is organized into flattened membranous sacs called ________; they, in turn, are arranged in orderly stacks called ________ that contain energy-transducing machinery.

1) thylakoids, grana
2) thylakoids, stroma
3) matrix, chlorophyll
4) stroma, grana
5) chlorophyll, thylakoids

Answer 1

The chloroplast's internal membrane contains flattened sacs called thylakoids, which are stacked into grana, surrounded by the stroma. The correct answer is 1) thylakoids, grana.

Step-by-step explanation:

The internal membrane of the chloroplast is organized into flattened membranous sacs called thylakoids. These are further arranged into orderly stacks known as grana, which contain the machinery necessary for energy transduction in photosynthesis.

The liquid-filled space surrounding the grana, contained within the chloroplast's inner membrane, is called the stroma. Therefore, the correct answer to the student's question is 1) thylakoids, grana.