Kidneys perform which function?

Options

A. Digestion
B. Reproduction
C. Excretion
D. Respiration

Answer

**Step-by-Step Solution:**

1. **Identify the Function of Kidneys**: The kidneys are primarily known for their role in the excretory system. Their main function is to filter blood and remove waste products from the body.

2. **Understand the Excretory System**: The excretory system is responsible for the elimination of waste materials from the body. The kidneys play a crucial role in this system by filtering out nitrogenous wastes.

3. **Recognize the Type of Waste**: The primary nitrogenous waste that the kidneys help to excrete is urea. Urea is produced from the breakdown of proteins and is a key component that needs to be removed from the bloodstream.

4. **Differentiate from Other Systems**: It is important to note that while other systems in the body (like the digestive and respiratory systems) also deal with waste, they do not specifically handle nitrogenous waste. For example, the lungs are involved in the exchange of gases (carbon dioxide and oxygen), not in the removal of nitrogenous waste.

5. **Conclude the Function of Kidneys**: Therefore, the main function of the kidneys is to act as excretory organs that filter blood and remove nitrogenous waste, primarily in the form of urea.

**Final Answer**: The kidneys perform the function of excretion by removing nitrogenous waste, primarily urea, from the body.

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