Explanation: An F1 (Formula One) car is primarily made of carbon fibre, a lightweight yet extremely strong and durable material. Carbon fibre provides high strength-to-weight ratio, excellent rigidity, and improved safety — essential for achieving high speeds and ensuring driver protection in racing conditions.

Hepatitis is a disease that primarily affects the liver. It is characterized by inflammation of the liver tissues and can be caused by viral infections (such as Hepatitis A, B, C, D, and E viruses), excessive alcohol consumption, toxins, or autoimmune conditions. Symptoms include jaundice (yellowing of the skin and eyes), fatigue, nausea, and abdominal pain. Severe or chronic hepatitis can lead to liver failure or cirrhosis if left untreated.

Other options (for context)

• Pancreas: Affected by diseases like pancreatitis or diabetes, not hepatitis.
• Spleen: Involved in blood filtration and immunity, not affected by hepatitis.
• Small intestine: Responsible for digestion and absorption of food, not linked to hepatitis.

Explanation: The onion is a modified underground stem called a bulb. It consists of a short, disc-like stem (the basal plate) surrounded by concentric fleshy leaf bases that store food. The roots emerge from the underside of the basal plate, and new shoots grow from the center. Thus, the onion bulb serves as a storage organ for nutrients and helps in vegetative propagation.

Explanation: The Bhopal Gas Tragedy occurred on the night of December 2–3, 1984, at the Union Carbide pesticide plant in Bhopal, Madhya Pradesh (India). The disaster was caused by the accidental leakage of Methyl Isocyanate (MIC), a highly toxic and reactive gas used in pesticide manufacturing. The poisonous gas spread rapidly over the nearby populated areas, killing thousands of people and causing severe respiratory and neurological disorders. It is considered one of the world’s worst industrial disasters.

Explanation: The DNA sequencing technique was developed by Frederick Sanger in 1977. His method, known as the Sanger chain termination method, determines the nucleotide sequence of DNA using labeled dideoxynucleotides (ddNTPs) that terminate DNA chain elongation. This technique revolutionized molecular biology and became the foundation for genome sequencing projects such as the Human Genome Project.

Nickel exposure commonly causes a skin disease called Dermatitis, specifically Allergic Contact Dermatitis. This condition occurs when the skin comes into direct contact with nickel-containing objects such as jewelry, coins, or belt buckles. It leads to redness, itching, and rashes, especially in sensitive individuals. Nickel allergy is one of the most common metal allergies worldwide.

Other options (for context)

• Itai Itai: Caused by cadmium poisoning, not nickel.
• Learning Disability: Not directly linked to nickel exposure.
• Asthma: May be aggravated by pollutants, but not typically caused by nickel.

Explanation: Fathom is a unit used to measure depth, particularly the depth of water in oceans and seas. One fathom is equal to 6 feet or approximately 1.83 meters. It is commonly used in navigation and marine studies.

Explanation: Mitochondria are double-membraned organelles found in almost all eukaryotic cells. They are known as the 'power house of the cell' because they generate adenosine triphosphate (ATP) through the process of cellular respiration. The inner membrane forms folds called cristae, which increase the surface area for enzyme activity related to energy production. Mitochondria also contain their own DNA and ribosomes, enabling them to produce some of their own proteins.

Key Reaction:

Glucose + Oxygen → Carbon dioxide + Water + ATP

The Biome is the largest ecological unit. It includes several ecosystems that share similar climate, vegetation, and animal life. Examples include tundra, desert, rainforest, and grassland. A biome represents a major community of living organisms adapted to a specific environment over large geographical areas.

• Organism: An individual living being.
• Population: A group of the same species living in an area.
• Ecosystem: Includes both living and non-living components, but multiple ecosystems together form a biome.

Explanation: Leguminous crops such as peas, beans, gram, and clover have a symbiotic relationship with Rhizobium bacteria in their root nodules. These bacteria convert atmospheric nitrogen into ammonia, enriching soil fertility naturally. Hence, legumes are used in crop rotation to restore nitrogen content in soil.