The Reason Red Blood Cells Only Live About 120 Days

question 21

Multiple Choice

The reason red blood cells only live about 120 days is because red blood cells

• A) lack a nucleus and therefore cannot defend themselves from pathogen attack.
• B) lack a nucleus and therefore cannot repair and rebuild cell structures.
• C) are attacked and eaten by white blood cells.
• D) are physiologically inferior cells that are not made to last very long.
• E) are destroyed by the high levels of oxygen they carry.

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Definitions:

Posttranslational Regulation Mechanism

Processes that modify a protein's function after it has been synthesized, impacting its activity, localization, or stability.

Proteolytic Processing

The enzymatic cleavage of protein precursors to form their active or mature states, a critical process in cellular regulation.

Chemical Modification

The alteration of a chemical compound's structure to change its properties or activity, often used in pharmaceuticals and materials science.

Protein Degradation

The process by which proteins are broken down into their amino acid components, often regulated by cellular mechanisms for metabolism and homeostasis.