Swine Flu is caused by the H₁N₁ virus, a subtype of the Influenza A virus. It primarily affects the respiratory system and is transmitted from person to person through droplets from coughs or sneezes. Symptoms include fever, cough, sore throat, body aches, and fatigue. The H₁N₁ pandemic in 2009 was declared a global health emergency by the World Health Organization (WHO).

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• Dengue: Caused by the Dengue virus, transmitted by Aedes mosquitoes.
• AIDS: Caused by the HIV (Human Immunodeficiency Virus), not H₁N₁.
• Bird flu: Caused by the H5N1 virus, not H₁N₁.

Sound waves from a loudspeaker are produced by vibrations of its diaphragm. When an electric current passes through the speaker coil, it causes the diaphragm to move back and forth, creating compressions and rarefactions in the air. These pressure variations travel as sound waves to our ears.

• Frequency: Determines pitch but does not create sound.
• Pitch: A property of sound, not its cause.
• Amplitude: Determines loudness but not the origin of sound.

Explanation: Malaria and Trichomoniasis are both protozoan diseases, not bacterial. Malaria is caused by Plasmodium species (transmitted by female Anopheles mosquitoes), while Trichomoniasis is caused by Trichomonas vaginalis, a sexually transmitted protozoan infection. Unlike bacterial diseases, these are treated using antiprotozoal drugs rather than antibiotics.

Explanation: A CD-ROM (Compact Disc Read-Only Memory) is an optical disk used to store large amounts of data. It is read using a laser beam in a CD drive and is commonly used for distributing software, music, and multimedia content.

The average distance between the Earth and the Sun is approximately 150 million kilometers (or about 1 Astronomical Unit – 1 AU). This distance serves as a standard unit of measurement for describing distances within our solar system. Despite slight variations due to Earth's elliptical orbit, this average remains nearly constant and is crucial for maintaining suitable conditions for life on Earth.

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• 15 Million km: Far too close — the Earth would be extremely hot and uninhabitable.
• 90 Million km: Shorter than the actual average distance.
• 900 Million km: Much greater — about six times the real distance, closer to Saturn’s orbit.

Explanation: The speed of internet connectivity is expressed in Megabits per second (Mb/sec or Mbps). It indicates how much data is transferred per second over a network connection. One megabit equals 1,000,000 bits. Higher Mbps values mean faster internet speeds. For example, a 100 Mbps connection can transfer 100 million bits of data every second. Note that 1 byte = 8 bits, so internet speeds in Mbps differ from file sizes, which are usually measured in megabytes (MB).

Explanation: Sugarcane (Saccharum officinarum) is a tall, jointed, perennial grass belonging to the family Poaceae. It has thick stems rich in sucrose, which is extracted to produce sugar. The plant reproduces mainly through stem cuttings (vegetative propagation). Its structure and growth habit are similar to other grasses like maize and bamboo.

The pale yellow colour of urine is due to the presence of the pigment Urochrome. Urochrome is a waste product formed from the breakdown of hemoglobin in red blood cells. It is produced when hemoglobin is metabolized into urobilin and then excreted through urine. The intensity of the yellow color can vary depending on hydration levels — darker urine indicates dehydration, while pale urine indicates proper hydration.

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• Urophyll: No such pigment exists in human physiology.
• Chlorophyll: Green pigment found in plants, not in urine.
• Chloroplast: Cell organelle in plants where photosynthesis occurs, not a pigment.