Question

The Grana and Stroma are the parts of which cell organelles
A. Mitochondria
B. Chloroplast
C. Ribosome
D. Golgi body

Answer 1

Hint: The grana and stroma are the parts of the cell organelle which is also known as the kitchen of the cell and is a semi-autonomous cell organelle like mitochondria found in plant cells.

Complete answer:
The grana and stroma are present inside the cell organelle chloroplast. It is a type of plastid. It is a double membraned cell organelle.

Additional Information:
Chloroplast has the following feature:
- The chloroplast contains three parts: the envelope, stroma, and the lamellar system.
- It is also known as the autoplast and the photosynthetic apparatus.
- Envelope: The envelope is a double membrane structure, the outer membrane is freely permeable but the inner membrane has shown selective permeability.
- Stroma or Matrix: Proteinaceous and consists of double-stranded circular DNA known as plastidome. The enzyme RUBISCO, which is also the most abundant enzyme on earth, is present in the stroma of the chloroplast.
- Lamellar System: It consists of thylakoids which are also double membrane-bound structures. They are also known as Baggy Trousers. Thylakoids are considered as the structural units of the chloroplast. 2-7 thylakoids are stacked together to form a structure known as grana. In-plant cells each chloroplast has a total of 40-60 grana but these are absent in the chloroplast of algae and bundle sheath cells of C4 plants.
- The inner membrane contains light-harvesting units known as quantasomes. These structures take part in photosynthetic reactions.

So, the correct answer is, ‘chloroplast’.

Note:
Chloroplasts are known as Semi-autonomous cell organelles because they have the following two features:
> They possess their own DNA, RNA, and ribosomes.
> They also possess their protein-synthesizing machinery.
> A chloroplast can be of a variety of shapes. In Chlamydomonas it is cup-shaped, in ulothrix it is girdle shaped, the spiral-shaped chloroplast is seen in spirogyra, and discoidal chloroplast is seen in higher plants.