Unlike most other cells in the human body, mature red blood cells (RBCs) do not contain a nucleus or mitochondria. This allows RBCs to carry more hemoglobin, and therefore oxygen, through the bloodstream. Based on the information above, which of the following is most likely true about RBCs? Choose 1 answer: A) RBCs generate lactate as a waste product. B Due to a lack of mitochondria, RBCs do not produce ATP. C
and ethanol are byproducts of ATP production in RBCs. D Oxygen is used as the terminal electron acceptor in RBCs.
The Correct Answer and Explanation is:
The correct answer is B) Due to a lack of mitochondria, RBCs do not produce ATP.
Explanation:
Mature red blood cells (RBCs) lack many organelles, including the nucleus and mitochondria. This unique feature is essential for their primary function: transporting oxygen. However, this also limits their ability to perform certain cellular processes, especially those that require energy production in mitochondria.
- Lack of Mitochondria: RBCs do not have mitochondria, which are the primary sites for ATP production through oxidative phosphorylation (a process that requires oxygen). Mitochondria are responsible for the electron transport chain and the production of ATP in most cells. Without mitochondria, RBCs cannot produce ATP through oxidative phosphorylation.
- Energy Production in RBCs: RBCs still need energy to carry out their functions, particularly the active transport of ions like sodium and potassium, as well as maintaining their structure and deformability. To meet their energy requirements, RBCs rely on anaerobic glycolysis (also known as the Embden-Meyerhof pathway), a process that occurs in the cytoplasm. In this pathway, glucose is converted to pyruvate, and ATP is produced without the need for oxygen. This means that RBCs do not depend on mitochondria for ATP generation.
- Other Answer Choices:
- A) RBCs generate lactate as a waste product: While lactate is produced as a byproduct of anaerobic glycolysis, the key point here is that RBCs rely on anaerobic glycolysis to generate ATP, not that lactate is the main focus. However, lactate is indeed produced, but it’s not the best answer here.
- C) Ethanol is a byproduct of ATP production in RBCs: Ethanol is not produced in RBCs. Ethanol is typically a byproduct of fermentation, which is different from the anaerobic glycolysis pathway that RBCs use.
- D) Oxygen is used as the terminal electron acceptor in RBCs: This is incorrect. RBCs do not perform oxidative phosphorylation because they lack mitochondria. Therefore, oxygen is not used as the terminal electron acceptor in RBCs.
Thus, the most accurate and relevant statement is B: RBCs do not produce ATP through mitochondrial processes due to the lack of mitochondria. Instead, they rely on anaerobic glycolysis to meet their energy needs.
