World Environment Day is celebrated on: ((MCAER 2014))

✅Explanation: Mitochondria are commonly known as the "powerhouses of the cell" due to their role in producing energy through cellular respiration.

📌 Other Options Explanations:
-Option B: The control centers of the cell are typically considered to be the nucleus.
-Option C: Protein factories are ribosomes.
-Option D: Packaging centers are the Golgi apparatus.

🔑Key Points:
-Mitochondria
-All eukaryotic cells have mitochondria, which are double membrane-bound organelles that generate adenosine triphosphate (ATP), the primary energy source required by the cell.
-It is commonly known as the "Powerhouse of the cell."
-Both plant and animal cells contain the double-membraned, rod-shaped mitochondria.
-Its diameter varies from 0.5 to 1.0 micrometres.
-The structure is made up of an inner membrane, an outer membrane, cisternae, the intermembrane space and matrix.
-The quantity of mitochondria differs from cell to cell.
-RBC which is a type of living cell lacks mitochondria, whereas liver cells have about 2000 per cell.
-In contrast to eukaryotes, bacteria do not have membrane-bound organelles like mitochondria or chloroplasts.
-Mitochondria without an outer membrane are called mitoplast.

🛑Additional Information:
-The mitochondria also perform signaling, cellular differentiation, cell death, and maintenance of cell cycle growth.
-Mitochondria have their own genetic material.
-The intermembrane space serves as a barrier between the layers of proteins and phospholipids that make up the outer membrane and the inner membrane.
-The mitochondrion's outer membrane is made up of numerous unique proteins called porins and covers its surface. 
-The genome of human mitochondria is circular DNA.