Problem 23 - Chemistry in 30 days

Question

Night blindness is caused by deficiency of (a) Vitamia \(\mathrm{B}_{13}\) (b) Vitamin \(\mathrm{A}\) (c) Vitamin C (d) Vitamin \(\mathrm{E}\)

Step-by-Step Solution

Answer

Night blindness is caused by a deficiency of Vitamin A (option b).

Step 1: Understanding the question

The question asks for the vitamin deficiency that causes night blindness. It provides four options to choose from.

Step 2: Recall knowledge about vitamins

Night blindness, also known as nyctalopia, is a condition that makes it difficult to see in low light or darkness. It is caused by a deficiency in Vitamin A, which is crucial for the maintenance of normal vision.

Step 3: Identifying the correct option

From the given options, Vitamin A is listed as option (b). Thus, option (b) is the correct answer as night blindness is caused by a deficiency of Vitamin A.

Key Concepts

Night Blindness

Night blindness, scientifically known as nyctalopia, is a condition where individuals struggle to see in dim light or darkness.
This doesn't mean complete blindness but rather a significant difficulty in adapting from well-lit environments to dark ones.

For those experiencing night blindness, simple tasks like driving at night or walking in dimly lit areas can become challenging.
This condition often serves as an early indicator of possible eye-health issues.

While it could be a symptom of several underlying issues, a common cause is a deficiency in Vitamin A.
The deficiency impairs the regeneration of rhodopsin, a pigment in the retina, essential for seeing in low-light conditions.
Without enough rhodopsin, the retina struggles to adapt to changes in light, leading to difficulties seeing in dim light scenarios.

Vitamin A

Vitamin A is a fat-soluble vitamin that plays a critical role in maintaining vision, especially in low-light conditions.
It is essential for many bodily functions, but its most well-known role is in vision health.

In the eye, Vitamin A gets converted into a molecule called retinal.
Retinal combines with opsin, a protein, to form rhodopsin, which is critical for light absorption in the retina.
This process is crucial, particularly in dim lighting or nighttime.

Additionally, Vitamin A supports skin health, boosts the immune system, and is vital for cell growth.
It can be obtained from dietary sources, primarily in two forms:

• Preformed Vitamin A (retinol) - Found in animal products like liver, fish oils, and eggs.
• Provitamin A (beta-carotene and other carotenoids) - Found in plant sources like carrots, sweet potatoes, and leafy greens.

For proper health, balance and adequate intake of these forms of Vitamin A are crucial.

Nutritional Deficiencies

Nutritional deficiencies occur when the body does not get enough of the nutrients it needs to function properly.
This can lead to a variety of health problems, one of which is night blindness, as caused by a shortage of Vitamin A.

There are several reasons why nutritional deficiencies may occur:

• Poor dietary choices that lack essential nutrients.
• Health conditions that impair nutrient absorption.
• Restricted diets due to allergies or lifestyle choices.

Vitamin A deficiency is particularly concerning because it's essential for vision.
Fortunately, it can be addressed effectively with a proper diet rich in Vitamin A.
In severe cases, medical intervention with supplements may be necessary to prevent further health issues.

Being proactive and maintaining a balanced diet can help prevent nutritional deficiencies and support overall well-being.