What is the function of the lysosomes in animal cells?
Show answer & explanation
Correct answer: B
Explanation
Correct Answer
Break down waste materials and cellular debris
Explanation
Lysosomes are spherical, membrane-bound organelles found in animal cells that function as the cell's waste disposal and recycling system. They contain highly acidic environments filled with powerful digestive enzymes (hydrolytic enzymes) capable of breaking down all types of biological polymers—including proteins, nucleic acids, carbohydrates, and lipids. Their primary role is to degrade worn-out cell parts, foreign substances (like bacteria or viruses), and cellular debris.
Other functions mentioned in the options belong to different organelles: proteins are transported by the endoplasmic reticulum and Golgi apparatus, ATP is produced by the mitochondria, and lipids are synthesized by the smooth endoplasmic reticulum.
Key Points
Lysosomes maintain a low internal pH (around 4.5 to 5.0), which is optimal for their digestive enzymes to function efficiently.
They protect the cell by engulfing and destroying invading pathogens such as bacteria and viruses through a process called phagocytosis.
They play a vital role in autophagy, which is the process of degrading and recycling the cell's own damaged or obsolete organelles to maintain cellular health.
When a cell is severely damaged or dead, lysosomes can rupture and release their digestive enzymes, causing the cell to digest itself.
Additional Facts
Due to their ability to completely destroy their own damaged host cell, lysosomes are commonly referred to as the "suicide bags" of the cell.
If the enzymes inside lysosomes are missing or defective due to a genetic mutation, waste products build up inside the cell, leading to severe metabolic conditions known as Lysosomal Storage Diseases (such as Tay-Sachs disease).
Important Questions and Answers
Question: Which specific type of enzymes are packed inside a lysosome to break down cellular waste?
Answer: Hydrolytic enzymes (or acid hydrolases) are the enzymes responsible for breaking down waste materials inside lysosomes.
Question: Which organelle is responsible for synthesizing and packaging the hydrolytic enzymes that are eventually sent to lysosomes?
Answer: The rough endoplasmic reticulum synthesizes the enzymes, and the Golgi apparatus modifies and packages them into lysosomes.