Problem 115 - Objective Biology for NEET

Question

An adult human excretes how much urine per day? (a) 1-1.5 litre (b) 1.5-2 litre (c) 5-1 litre (d) 3 litre

Step-by-Step Solution

Answer

The urine excretion per day by an adult human is between 1-2 litre i.e., option (a) or option (b).

Step 1: Analyse the Options

Look through the options presented to determine if the answer can be rationalised. The options given vary quite a bit, from 1 litre per day up to as much as 5 litres.

Step 2: Use Biological Knowledge

Refer to biological knowledge or resources to know that the average urine output of an adult human is about 1 to 2 litres per day. This is a well-known basic fact about the human body.

Step 3: Choose the Correct Answer

From the given options, the one that falls within this range is (a) 1-1.5 litres and (b) 1.5-2 litres.

Key Concepts

Urine Output

Urine output refers to the amount of urine produced and excreted by the kidneys each day. It is an important indicator of kidney function and overall body fluid balance. In adult humans, the average urine output ranges from 1 to 2 liters per day. This volume can fluctuate depending on several factors:

• Fluid intake: Higher fluid intake typically results in higher urine output, while lower intake reduces it.
• Environmental conditions: Hot and humid conditions may lead to sweating and decreased urine production, whereas cool environments may increase urine output.
• Physical activity: Engaging in intense physical activity can cause sweating and temporarily decrease urine output.
• Medical conditions: Certain health issues may affect urine output, such as diabetes or kidney disorders, causing it to increase or decrease significantly.

Understanding these factors helps one to assess whether changes in urine output are normal or indicative of a health issue.

Adult Human

An adult human is typically considered to be a person aged 18 years or older. At this stage of life, numerous physiological processes stabilize, providing a baseline for understanding various bodily functions, like urine output.
Adults generally maintain a state of homeostasis, where internal conditions remain stable and consistent despite external changes. For instance, an average adult consumes about 2 to 3 liters of water every day, which aligns with the expected 1 to 2 liters of urine output. This balance is essential for:

• Regulating body temperature: Through mechanisms like sweating and urination.
• Removing waste: Urine helps dispose of metabolic waste and excess substances.
• Maintaining electrolyte balance: Ensures proper function of cells and organs.

Recognizing these typical patterns in adults can assist in identifying any anomalies that require medical attention.

Biological Knowledge

Biological knowledge encompasses understanding how living organisms function and interact with their environment. When it comes to the excretory system, basic biological knowledge helps explain why humans produce urine and what it signifies.
The kidneys filter blood to remove waste and extra water, producing urine in the process. This biological function maintains:

• Homeostasis: By regulating body fluids, electrolytes, and waste products.
• Blood pressure: Through fluid management, kidneys play a role in controlling blood pressure.
• Toxin elimination: Helps remove harmful substances from the body.

Drawing from biological facts about the human body, one can assess average ranges, like the 1 to 2-liter daily urine output, and recognize deviations as possible symptoms of health problems.