Which of the following describes a lysosome?
Multiple Choice
A double-membraned organelle that is the “powerhouse” of the cell.
A tiny, membranous sac that contains enzymes that degrade worn cell parts and debris.
A nonmembranous structure that is essential for mitosis.
A complex network of interconnected membranes that is a communication system within the cell.
The Correct Answer and Explanation is :
The correct answer is:
A tiny, membranous sac that contains enzymes that degrade worn cell parts and debris.
Explanation:
Lysosomes are membrane-bound organelles that play a crucial role in the degradation and recycling of cellular waste, damaged organelles, and foreign materials. They are often referred to as the cell’s “garbage disposal” or “clean-up” system. Lysosomes contain hydrolytic enzymes, which are capable of breaking down a variety of substances, including proteins, lipids, carbohydrates, and nucleic acids. These enzymes are active at the acidic pH maintained inside the lysosome, which is crucial for their function.
Lysosomes form from the Golgi apparatus, and their primary function is to digest unwanted material within the cell. For instance, when an organelle or other cell component becomes damaged, the lysosome fuses with the damaged part, releasing its enzymes to break it down into simpler components that can either be recycled for new cellular processes or excreted as waste. They are also involved in processes such as autophagy (the breakdown of the cell’s own components) and endocytosis (the uptake and digestion of materials from outside the cell).
The other options are incorrect because:
- A double-membraned organelle that is the “powerhouse” of the cell refers to the mitochondrion, which is responsible for energy production in the form of ATP.
- A nonmembranous structure that is essential for mitosis refers to the centrosome, which plays a key role in organizing microtubules during cell division.
- A complex network of interconnected membranes that is a communication system within the cell describes the endoplasmic reticulum, which is involved in protein and lipid synthesis and plays a role in intracellular signaling.
In summary, lysosomes are essential for maintaining cellular homeostasis by breaking down and recycling waste materials and cellular debris.