GK (General Science) - 7

EVE (Electro-Voltaic Embryogenesis) is a biotechnological technique used for creating designer babies through genetic selection and manipulation. This involves choosing specific genetic traits before birth. The other options are incorrect: eye disease is medical (EVE is not a disease), mirror and lens are optical objects unrelated to embryogenesis.

The Pauli Exclusion Principle states that no two electrons in an atom can have identical sets of four quantum numbers (n, l, ml, ms). This explains electron arrangement in orbitals and the structure of the periodic table. Hund's rule deals with electron pairing in degenerate orbitals. Bohr's model is about electron orbits. Heisenberg's principle is about position-momentum uncertainty.

Marie Curie coined the term 'radioactivity' in 1898 to describe the spontaneous emission of radiation from atomic nuclei. Henri Becquerel discovered radioactivity (through uranium), but Curie named it. Rutherford contributed to nuclear physics understanding. De Broglie proposed wave-particle duality.

Nuclear stability is primarily determined by the neutron-to-proton (N/P or n/p) ratio in the nucleus. Stable nuclei have optimal N/P ratios that balance nuclear forces. Too few or too many neutrons leads to instability and radioactivity. Half-life measures decay rate, not stability. P/N ratio is same as N/P but less common notation. R/n is not a standard concept.

Hydrogen bombs (thermonuclear weapons) are based on nuclear fusion - combining light atomic nuclei (like isotopes of hydrogen) to form heavier ones, releasing massive energy. Nuclear fission is used in atomic bombs. The bomb requires fission to trigger fusion initially, but the main destructive yield comes from fusion, not fission alone.

Rain water is the purest form of natural water because it forms through the process of evaporation and condensation, which naturally removes most impurities. River water contains dissolved minerals and pollutants from the ground it flows over, filtered water still contains some dissolved substances, and mineral water has added minerals for taste.

James Chadwick discovered the neutron in 1932 through experiments involving alpha particle bombardment of beryllium. J.J. Thompson discovered the electron, Goldstein discovered the proton (canal rays), and Yukawa proposed the meson theory. Chadwick's discovery completed the picture of the three main subatomic particles.

A redox reaction always involves both oxidation (loss of electrons) and reduction (gain of electrons) occurring simultaneously. Electrons lost by one species must be gained by another - they cannot exist freely. The term 'redox' itself comes from combining 'reduction' and 'oxidation'.

The Ostwald process is the industrial method for producing nitric acid from ammonia. It involves three steps: oxidation of ammonia to NO, oxidation of NO to NO2, and absorption of NO2 in water. The Haber process produces ammonia, Contact process produces sulfuric acid, and Lead chamber process is an older method for sulfuric acid production.

Tides are the periodic rise and fall of sea water levels caused primarily by the gravitational pull of the moon and, to a lesser extent, the sun. Waves are caused by wind, and 'fiction' appears to be a typo or distractor. Tides occur in regular intervals depending on the lunar cycle.

Primary cells are non-rechargeable batteries that cannot be restored to their original chemical state once discharged. The Voltaic, Daniel, and Leclanche cells are all primary cells. Lead-acid cells are secondary cells that can be recharged multiple times by applying an external current to reverse the chemical reaction.

Tapeworms are parasitic flatworms that infect the human intestine, where they attach to the intestinal wall and absorb nutrients. Earthworms are beneficial soil organisms, and Anopheles is a mosquito genus (not a worm) that can transmit malaria. The question asks specifically about worms that infect human intestines.

Both bismuth and antimony are diamagnetic materials, meaning they are weakly repelled by a magnetic field and do not retain magnetic properties when the external field is removed. Diamagnetic substances have all their electrons paired and no permanent magnetic moment. This property contrasts with paramagnetic and ferromagnetic materials.

Mach 2 refers to twice the speed of sound, which only supersonic aircraft can achieve. Subsonic aircraft fly below the speed of sound (Mach 1), and 'light aircraft' refers to weight classification, not speed. The term 'Mach number' is specifically used to express the ratio of flow velocity to the speed of sound.

Umbra refers to the darkest part of a shadow during an eclipse, where the light source is completely blocked. It represents total darkness. Penumbra is the term for partial darkness where only part of the light source is blocked. The other options (fluorescent, incandescent) refer to light-producing mechanisms, not shadow concepts.

Chloroacetophenone (CN gas) is commonly known as tear gas, a lachrymatory agent that causes severe eye irritation, tearing, and temporary blindness. LSD is a hallucinogenic drug, 'Dishlorodiethyl Sulphide' appears to be a misspelling of sulfur mustard (mustard gas), and TNT is an explosive. Tear gas is used for riot control and police operations.

Zinc oxide is historically known as 'philosopher's wool' or 'nix alba' because when it forms as a white, wool-like precipitate during the burning of zinc, it resembles wool. The other options appear to be made-up or misspelled terms. This historical name comes from alchemical traditions.

The Pacific Ocean is the largest and deepest ocean on Earth. It covers approximately one-third of Earth's total surface area, which is about 165 million square kilometers. This makes it significantly larger than any other ocean and contributes to its status as both the largest by area and deepest by maximum depth.

Mercury expands uniformly with temperature changes, which is essential for accurate temperature measurement. This uniform expansion is a key reason mercury is used in thermometers. The other options are actual advantages: mercury is opaque and visible (B), conducts heat well (C), and doesn't stick to glass (D). The question asks which is NOT a correct reason, and since mercury DOES expand uniformly, option A is the correct answer.

In the additive color model (used for light and displays), the primary colors are red, green, and blue (RGB). Yellow is a secondary color formed by mixing red and green light. In subtractive color mixing (paints and pigments), yellow is considered a primary color along with magenta and cyan (or traditionally red, yellow, and blue). The question is referring to the additive color model.

Isobars are atoms of different elements with the same mass number but different atomic numbers. This means they have the same total number of nucleons (protons + neutrons) but different numbers of protons. For example, 40Ar (Argon, Z=18) and 40Ca (Calcium, Z=20) are isobars. Isotopes have the same atomic number but different mass numbers, while isotones have the same number of neutrons.

Quinine is a traditional medication used both to treat malaria (cures) and as a prophylactic to prevent malaria infection. It is derived from the bark of the cinchona tree and has been used for centuries. Ergovine affects blood vessels, morphine is a painkiller, and atropine has anticholinergic effects - none of these are antimalarials.