Minerals and Nutrients

Statement 1 is correct. Barium sulphate in suspension is frequently used clinically as a radiocontrast agent for X-ray imaging and other diagnostic procedures. Statement 2 is also correct. Zinc compounds are mostly found in human tears.

 Chlorine helps in the photolysis of water. Photolysis is part of the light-dependent reactions of photosynthesis.

Tyrosinase is a rate limiting enzyme which controls melanin production. Tyrosinase is involved in the hydroxylation of monophenol and also the conversion of o-diphenol to corresponding o-quinone. The enzyme tyrosinase consists of copper and is found in animal and plant tissues. The active site of all tyrosinases contains one binuclear copper centre. Tyrosinase catalyzes melanin production and in humans it is encoded by TYR gene.

Calcium is essential for the clotting of blood.

Sodium ions are present in maximum concentration in blood plasma. The normal concentration range is 135 - 145 mmol/l.

Dietary supplement of Ca and vitamin D because parathormone maintains Ca and P within narrow range. Vitamin D increases the resorption of P

Calcium is a major component of our bones and teeth. Iron is present as haemoglobin in blood and iodine is required for the regular body metabolism. Mercury is poisonous for our health and can lead to death even if taken in small amount. 

Biogeochemical cycle can be broken down into 2 types of local cycles, such as phosphorus cycle, which involves elements with no mechanisms for long distance transfer, and global cycles, which invoke an interchange between the atmosphere and the ecosystem.

Helium (He) is a noble gas with electron configuration 1s², placing it in the p-block of the periodic table (Group 18). While it fills the 1s orbital, helium is classified with other noble gases due to its similar chemical properties. Cs, Mg, and Ca are all s-block elements - Cs is in Group 1 (alkali metals) while Mg and Ca are in Group 2 (alkaline earth metals).

Chlorophyll, the green pigment responsible for photosynthesis in plants, contains a magnesium ion (Mg²+) at the center of its porphyrin ring structure. This central Mg is crucial for chlorophyll's ability to absorb light energy.

 Chlorine is a micronutrient required by a plant. The rest are macronutrients.

Sufficient amount of iodine is required by our body for maintaining a balanced mental status.

Oxygen (46-47%) and silicon (27-28%) are the two most abundant elements in Earth's crust by mass. Oxygen is found in silicates, oxides, and water. Silicon is the second most abundant and is the foundation of silicate minerals that make up most rocks. Options A, B, and C are incorrect because while iron, magnesium, and aluminum are abundant, they rank below oxygen and silicon. Aluminum is actually the third most abundant (~8%), followed by iron (~5%) and calcium (~3.6%).

Plants require sixteen essential elements for growth, but nitrogen (N), phosphorus (P), and potassium (K) are needed in the largest quantities - these are the primary macronutrients. Among all nutrients, nitrogen is typically required in the greatest amount as it's a crucial component of amino acids, proteins, chlorophyll, and nucleic acids. Calcium, ammonia (which provides nitrogen), and phosphorus are also important but not needed in quantities as large as nitrogen.

Oxygen is the most abundant element in Earth's crust, constituting approximately 46-47% by weight. This is primarily in the form of silicate minerals, oxides, and water. Silicon is the second most abundant at about 27-28%, followed by aluminum at about 8%. Carbon, nitrogen, and hydrogen are present in much smaller quantities in the crust despite being abundant in the atmosphere and living organisms.