Problem 52 - Objective Biology for NEET

Question

Hypothyroidism is caused by (a) Cancer of thyroid gland (b) Development of nodule of thyroid gland (c) Iodine deficiency (d) Both (a) and (b)

Step-by-Step Solution

Answer

The correct answer is (c) Iodine deficiency.

Step 1: Understand Hypothyroidism

Hypothyroidism is a disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormone. It can be caused by a number of factors.

Step 2: Cancer of Thyroid Gland and Development of Nodule

Cancer of the thyroid gland or development of a nodule of thyroid gland can lead to hypothyroidism. These conditions may alter the functionality of the gland, but they do not directly lead to decreased production of thyroid hormone as unless the gland is completely destroyed or removed.

Step 3: Iodine Deficiency

Iodine is an essential factor that the thyroid gland needs to produce thyroid hormones. Therefore, if there is a deficiency of iodine, it directly impacts the production of thyroid hormones, leading to hypothyroidism.

Step 4: Select the Right Answer

With the above information, it can be determined that the cause of hypothyroidism is due to iodine deficiency. Thus, the right choice is (c) Iodine deficiency.

Key Concepts

Understanding the Endocrine System

The endocrine system is a network of glands that produce and release hormones directly into the blood. These hormones regulate activities throughout your body including metabolism, growth, and mood. The thyroid gland is a key player in this system and is located at the front of the neck. It produces hormones that control the rate at which your body uses energy. The interaction within this system is intricate, interconnected, and balances the body’s needs.

• Hormones act as messengers that affect the function of cells and organs.
• The hypothalamus, pituitary gland, thyroid, and adrenal glands are major components of this system.
• A healthy endocrine system maintains homeostasis and adjusts to changes in the environment.

When issues arise in this system, such as an underactive thyroid, it can lead to conditions like hypothyroidism. Understanding these relationships is crucial for comprehending how systemic disorders occur.

The Role of Iodine Deficiency

Iodine is a critical mineral required for the production of thyroid hormones. Without adequate iodine, the thyroid gland cannot produce enough hormones to meet the body's needs, causing hypothyroidism. This is because iodine is a key component in the synthesis of these hormones.
Iodine deficiency is a widespread issue that can lead to significant health problems. It is especially common in areas where the soil is lacking in iodine.

• Dietary sources of iodine include fish, dairy products, and iodized salt.
• Deficiency can lead to thyroid enlargement, known as goiter.
• Ensuring sufficient iodine intake is vital for thyroid health.

In many parts of the world, iodine deficiency continues to be a significant health problem, emphasizing the importance of monitoring and supplementing iodine in diets.

Importance of Thyroid Hormones

Thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3), are vital for regulating the body's metabolism. They influence how fast or slow your body work by controlling the speed of energy usage, protein creation, and sensitivity to other hormones.
These hormones have several crucial functions:

• Assist in energy consumption and metabolic rate.
• Facilitate proper development and growth during childhood.
• Affect the function of various bodily systems such as cardiovascular and neurological systems.

Lack of adequate thyroid hormone production leads to hypothyroidism, resulting in symptoms like fatigue, weight gain, and depression. It is essential to maintain the right hormone levels for optimal health and well-being. Treatments are available, including medication that supplements hormone levels artificially, ensuring the body receives what it lacks.