Problem 134 - Objective Biology for NEET

Question

Malfunctioning of kidney may lead to the accumulation of _______ in blood. (a) Glucose (b) Amino acid (c) Urea (d) All of these

Step-by-Step Solution

Answer

The answer is (d) All of these. In case of kidney malfunction, all of these substances - glucose, amino acid and urea could accumulate in the blood.

Step 1: Understanding kidney function

Lets first understand what are the main roles of the kidneys. The kidneys filter out many substances from the blood including glucose, amino acids, and urea. They maintain the balance of these substances and prevent their accumulation in the blood.

Step 2: Understanding consequences of kidney malfunction

Next, we have to imagine what might happen if the kidneys fail to perform their function properly. If they malfunction, they may not be able to filter out these substances as they normally would. This could lead to their accumulation in the blood.

Step 3: Answering the question

Given the above understanding, it can be determined that in case of kidney malfunction, all of these substances - glucose, amino acid and urea could accumulate in the blood. So, the correct answer is (d) All of these.

Key Concepts

Kidney Malfunction

Kidneys are vital organs responsible for filtering waste products and balancing various substances in the blood. When they malfunction, this ability is compromised. A malfunction can be due to various reasons such as diabetes, hypertension, or infection. When kidneys do not work properly, they cannot effectively remove waste products from the blood.
As a result, substances that should be filtered out remain in the bloodstream. This not only affects detoxification but can also disrupt the body's overall chemical balance. Symptoms of kidney malfunction can include swelling, fatigue, and changes in urination. Early detection and management are crucial to prevent further complications.

Blood Composition

Blood is a complex fluid composed of red blood cells, white blood cells, platelets, and plasma. Plasma, the liquid part, carries nutrients and waste products like urea. The kidneys' role is to regulate the components in blood, ensuring waste is excreted and essential nutrients are conserved.
Normal blood composition is key to maintaining energy levels, bodily functions, and oxygen transport. Any disruption, caused by kidney malfunction, can lead to an imbalance of substances in blood composition. This can cause clinical symptoms and increased risk of chronic diseases.

Urea Accumulation

Urea is a waste product formed from the breakdown of proteins in the body. It is normally cleared from the blood by the kidneys via urine. If the kidneys fail to function properly, urea builds up in the blood, a condition known as uremia. High levels of urea can be toxic and lead to nausea, fatigue, and confusion.

• Urea is primarily formed in the liver.
• The kidneys filter out urea through a process that helps maintain nitrogen balance.
• Accumulation of urea is a primary indicator of kidney dysfunction.

Monitoring urea levels is essential for diagnosing and managing kidney-related issues.

Nephrons

Nephrons are the microscopic functional units of the kidney, each kidney containing about a million of them. They filter blood, removing waste and excess substances. Their main components include the glomerulus and tubule:

• Glomerulus: A tiny blood vessel cluster where filtration begins.
• Tubule: Processes the filtered fluid, reabsorbing water and nutrients while excreting waste.

Each nephron works tirelessly to regulate the body's chemical balance. Any damage or decrease in their number can lead to impaired kidney function, contributing to the accumulation of waste products in the blood.

Filtration Process

The filtration process is crucial for kidney function and involves filtering blood to remove waste products. It starts at the glomerulus, where blood pressure pushes small molecules like glucose, amino acids, and urea into the surrounding nephron tubules.
Large molecules like proteins remain in the bloodstream. Once in the tubules, these substances are reabsorbed or secreted as needed:

• Reabsorption: Essential molecules such as glucose are reabsorbed into the bloodstream.
• Excretion: Waste products are concentrated into urine.

This ongoing process ensures the body maintains a balanced internal environment, and any disruption can result in the accumulation of unwanted substances.