Which one of the following statements is correct?
Which one of the following statements is correct?
All enzymes that utilise ATP in phosphate transfer require Ca as the cofactor
The bone in human body is an inert and unchanging substance
The daily requirement of Mg and Ca in the human body is estimated to be 0.2-0.3 g
Mg plays roles in neuromuscular function and interneuronal transmission
The Correct Option is D
Solution and Explanation
The correct answer is Option 4: Mg plays roles in neuromuscular function and intraneuronal transmission.
Magnesium (Mg) is an essential mineral and cofactor that plays a critical role in various biochemical reactions in the human body. It is especially important in the functioning of the nervous and muscular systems. Mg helps regulate neurotransmitter release, muscle contraction, and nerve signal transmission, making it vital for both neuromuscular function and intraneuronal communication.
Explanation of all options:
Option 1: "All enzymes that utilise ATP in phosphate transfer require Ca as the cofactor" – This statement is incorrect. Although calcium (Ca) does act as a cofactor for certain enzymes, most ATP-dependent reactions actually require magnesium (Mg) as the true cofactor. Mg stabilizes ATP molecules by binding to the phosphate groups, making it essential for enzyme catalysis involving ATP.
Option 2: "The bone in human body is an inert and unchanging substance" – This is a misconception. Bone is a living tissue that continuously undergoes remodeling. It actively participates in mineral storage, blood cell formation (hematopoiesis), and responds to mechanical and metabolic stress. Therefore, it is not inert or unchanging.
Option 3: "The daily requirement of Mg and Ca in the human body is estimated to be 0.2–0.3 g" – This statement is incorrect. The daily recommended intake for calcium in adults is around 1000–1200 mg (1–1.2 g), and for magnesium, it ranges between 300–400 mg. The combined requirement of 0.2–0.3 g is a significant underestimation.
Option 4: "Mg plays roles in neuromuscular function and interneuronal transmission" – This is the correct statement. Magnesium is vital for regulating ion channels, especially calcium and potassium, which are crucial for proper muscle contractions and nerve signal propagation. A deficiency in Mg can lead to muscle cramps, spasms, and neurological issues.
In conclusion, magnesium's crucial role in both neuromuscular and neuronal functions makes Option 3 the best and most scientifically accurate choice among the given options. Understanding the physiological significance of minerals like Mg and Ca is essential for mastering human biology, especially for competitive exams like NEET.
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Concepts Used:
Proteins
An essential part of every cell in our body, protein is one of the three macronutrients which is required by our body in larger amounts. Proteins are made up of linear chains of smaller units called amino acids. Every biochemical process that takes place inside our bodies is possible because of these proteins. Proteins are 3-dimensional structures that are assembled with different amino acid sequences.
Functions of Protein
Proteins are used in many ways. Some of their functions are:
- Enzymes: Most of the important chemical reactions which take place inside a cell are mostly carried out by enzymes. They also play a role in regenerating and creating DNA molecules and carrying out complex processes.
- Hormonal Regulation: Proteins create various types of hormones that help in balancing the components of the body. For example, hormones like insulin help in regulating blood sugar and secretin. The formation of digestive juices essential for the whole digestion process is also possible because of hormones.
- Protection: Being the main constituent of antibodies, proteins protect our body against antigens and pathogens thus preventing infections.
- Energy: Proteins are one the most essential sources of energy required for our body movements. The right amount of proteins should be consumed so that they can be turned into energy.
- Structural functions: Proteins are the building blocks of the body. They are required for the growth, development, healing, and repair of tissues. Proteins are essential in order to strengthen various structures like hair, skin, and muscles. It is also present in the outer membrane of all cells in the human body.
Classification of Protein
Proteins are classified on the basis of:
- Shape
- Constitution
- Nature of Molecules
Protein Structure
A protein molecule is made from a long chain of amino acids, each linked to its neighbor through a covalent peptide bond. The structure of proteins are divided into four types:
- Primary Structure
- Secondary Structure
- Tertiary Sector
- Quaternary Structure