Question

The structure that is formed by stacking of organized flattened membranous sacs in the chloroplasts are
A. Stroma lamellae
B. Stroma
C. Cristae
D. Grana

Answer 1

Hint: Across all green plants and algae, chloroplasts are found. They are the manufacturers of plants' food. These are present in the guard cells which are located in the plants' leaves. They contain significant amounts of light from the sun-trapping chlorophyll.

Complete answer:
The chloroplast is an organelle that comprises chlorophyll, a photosynthetic pigment that absorbs and converts sunlight into an energy source and thereby releases oxygen from the water. The chloroplast will have its own DNA and can reproduce independently from the rest of the cell. They also provide the amino acids and lipids desired for chloroplast membrane manufacturing. Thylakoids are stacked in piles like a stack of coins called grana in the chloroplast, which seem to be green-colored plastids. Grana are connected by stromal lamellae, extensions that run it into neighboring granum through one granum, via the stroma. A core aqueous region known as the thylakoid lumen is enclosed by the thylakoid membrane. A stack of thylakoid discs is a granum. Chloroplasts can have between 10 and 100 granules. Grana, also called intergranal thylakoids or lamellae, are associated with stroma thylakoids. Grana thylakoids and stroma thylakoids can be categorized by various concentrations of protein.
So, the correct answer is option (D).
Additional Information:
When seedlings arise from the ground, chloroplasts form from proplastids. Light includes Thylakoid formation. Using a combination of differential and gradient centrifugation, thylakoids can be extracted from plant cells. As well as lumenal proteins, thylakoids contain numerous integral and peripheral membrane proteins. Yet more data on the protein level of thylakoids were given by recent proteomics analyses of thylakoid fractions. Grana is an array of structures known as thylakoids, which are cell membrane discs on which photosynthetic activity reactions are light-dependent.

Note: The grana thylakoids are organized in the form of cylindrical piles and are linked via tubular junctions in higher-order plants to the stroma thylakoids, and electron tomography has defined this.