Cell Biology

Concept: Cells contain specialized structures called organelles, each performing a specific function. The mitochondria are responsible for producing energy required for cellular activities. Mitochondria generate energy in the form of ATP (Adenosine Triphosphate) through the process of cellular respiration. Because they supply energy to the cell, they are commonly referred to as the "powerhouse of the cell".
Step 1: Understanding the role of mitochondria.
Mitochondria break down glucose and other nutrients in the presence of oxygen to produce ATP, which powers metabolic activities such as movement, synthesis of molecules, and active transport.
Step 2: Eliminating other options.

• Nucleus controls genetic information and cell activities.
• Ribosomes are responsible for protein synthesis.
• Golgi apparatus modifies and packages proteins for transport.

Thus, the organelle known as the powerhouse of the cell is mitochondria.