56th-59th Prelims 2015

Explanation:

Cloves are obtained from the dried flower buds of the clove plant (Syzygium aromaticum). The buds are harvested before opening and dried to produce the aromatic cloves used in cooking and medicine. Cloves contain eugenol, known for antioxidant, anti-inflammatory, and antimicrobial properties.

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Oncogenes are genes that regulate cell growth and division. When they are abnormally activated, they can cause uncontrolled cell proliferation, leading to cancer. They are not related to infectious diseases like tuberculosis, hepatitis, or typhoid.

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Among the options, potassium is the most reactive metal. The reactivity of metals depends on their tendency to lose electrons. Alkali metals like potassium and sodium are highly reactive, with potassium at the top of the reactivity series, making it more reactive than sodium, calcium, and iron.

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Arthur Kornberg synthesized DNA in vitro, meaning outside living cells in a test tube. He discovered DNA polymerase and successfully replicated DNA molecules, which earned him the Nobel Prize in Physiology or Medicine in 1959. This was a landmark achievement in molecular biology.

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The bomb dropped on Nagasaki, known as 'Fat Man', used plutonium as its fissionable material. It was an implosion-type nuclear weapon, distinct from the uranium-based bomb dropped on Hiroshima.

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Nicolaus Copernicus, a Polish astronomer, proposed the heliocentric model of the solar system in the 16th century, placing the Sun at the center and the Earth in orbit around it. This challenged the geocentric model that placed Earth at the center.

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Cosmic rays are primarily charged particles, mostly protons (hydrogen nuclei) and alpha particles (helium nuclei), along with some electrons. Their charged nature causes them to be deflected by magnetic fields as they travel through space.

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Carbon is the fundamental element of organic chemistry. Organic compounds are defined as compounds containing carbon atoms bonded to hydrogen and often other elements like oxygen, nitrogen, and sulfur. Calcium, nitrogen, and oxygen are not essential for all organic compounds.

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Ionized radiation, such as X-rays and gamma rays, can damage DNA at high intensities causing cancer, but controlled doses are used in radiation therapy to destroy cancer cells. Tobacco, alcohol, and ultraviolet rays can cause cancer but are not used therapeutically.

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A normal adult has approximately 5-6 liters of blood. Blood functions in oxygen transport, nutrient delivery, waste removal, immune defense, blood clotting, and hormone transport. It circulates through arteries, veins, and capillaries.

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Typhoid and cholera are waterborne diseases transmitted via contaminated water or food. Typhoid is caused by Salmonella typhi, and cholera by Vibrio cholerae.

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Energy in liver and muscles is stored as glycogen, a polysaccharide made from glucose. Glycogen serves as a glucose reserve that can be broken down to provide energy during fasting or physical activity.

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Antonie van Leeuwenhoek, using powerful microscopes in the 17th century, observed bacteria and called them 'animalcules'. He is considered the father of microbiology.

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Large-scale diversity arises primarily from adaptation, where organisms acquire traits to survive and reproduce in their environment. Mutation, polyploidy, and cooperation also contribute but are not the main drivers of diversity.

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Vermiculture is the science of cultivating worms to decompose organic waste and produce nutrient-rich vermicompost. It is used in sustainable agriculture and waste management.

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Mycoplasma is the smallest organism capable of independent growth and reproduction. Unlike viruses or bacteriophages, it does not require a host cell and lacks a cell wall.

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The first human heart transplant was performed by Dr. Christiaan Barnard on December 3, 1967, at Groote Schuur Hospital in Cape Town, South Africa. The recipient was Louis Washkansky.

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The kidneys receive approximately 1200 cc of blood per minute to filter waste, maintain fluid balance, and produce urine. Each kidney contains nephrons that perform filtration, reabsorption, and urine formation.

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A plant bud is an embryonic shoot that can develop into stems, leaves, or flowers. Embryonic leaves are part of the bud, endosperm is nutrient tissue in seeds, and a seed is a mature ovule containing an embryo.

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Butane is a hydrocarbon gas used in cigarette lighters due to its high flammability and low boiling point. It vaporizes easily and ignites when exposed to a spark. Methane and propane are used in heating and cooking, while radon is radioactive.