Question

what is granum......................

Answer 1

Chloroplasts are a type of plastid—a round, oval, or disk-shaped body that is involved in the synthesis and storage of foodstuffs. They are enclosed in a chloroplast envelope, which consists of a double membrane with outer and inner layers, between which is a gap called the intermembrane space. A third, internal membrane, extensively folded and characterized by the presence of closed disks (or thylakoids), is known as the thylakoid membrane. In most higher plants, the thylakoids are arranged in tight stacks called grana (singular granum).
For more, refer to:
https://www.britannica.com/science/photosynthesis/Energy-efficiency-of-photosynthesis#ref366098

Answer 2

Granum is the collective term used for defining the stacks of thylakoids within the chloroplast of the plant.Granum is composed of chlorophyll and phospholipids.It contains the light harvesting system of plant