Which of the following is incorrect about the excretory system of human?

Options

A. About 10 million nephrons are found in each kideny.
B. The right kidney is located lower than that of the left kidney.
C. Ultraflitration occurs at the level of Bowman's capsule
D. Longer the loop of Henle more will be the concentration of urine.

Answer

To determine which statement is incorrect about the excretory system of humans, let's analyze each option step by step.

**Step 1: Analyze the first option**
- The statement claims that about 10 million nephrons are found in each kidney.
- In reality, each human kidney contains approximately 1 million nephrons, not 10 million. Therefore, this statement is incorrect.

**Step 2: Analyze the second option**
- This option states that the right kidney is located lower than the left kidney.
- This is true because the right kidney is positioned lower than the left kidney to accommodate the liver, which is a larger organ. Hence, this statement is correct.

**Step 3: Analyze the third option**
- The statement mentions that ultrafiltration occurs at the level of Bauman's capsule.
- This is also true. Ultrafiltration occurs in the glomerulus, and the filtrate is collected in Bowman's capsule (also known as the glomerular capsule). Thus, this statement is correct.

**Step 4: Analyze the fourth option**
- The statement claims that the longer the loop of Henle, the more concentrated the urine will be.
- This is true as well. A longer loop of Henle allows for greater reabsorption of water and sodium chloride, leading to more concentrated urine. Therefore, this statement is correct.

**Conclusion:**
After analyzing all the options, the first option is the incorrect statement. Each kidney contains about 1 million nephrons, not 10 million.

**Final Answer:**
The incorrect statement about the excretory system of humans is: "About 10 million nephrons are found in each kidney."

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