General Science Questions (MCQs) for Competitive Examinations

Notes:
A tannin is an astringent, bitter plant polyphenolic compound that binds to and precipitates proteins and various other organic compounds including amino acids and alkaloids. It refers to the use of wood tannins from oak in tanning animal hides into leather.

Notes:
Animals that ingest bulk food unavoidably take in some matter that they are incapable of using. Substances that cannot be digested, such as cellulose, pass into the colon, or large intestine. Egestion is the passing out of undigested food as faeces, through the anus.

Notes:
Gambusia affinis, also known as Mosquito fish, is a species of freshwater fish that is introduced directly into ecosystems as a biocontrol to lower mosquito populations. The diet of this fish sometimes consists of large numbers of mosquito larvae. Gambusia affinis has turned out to be indispensable to modern Mosquito/Malaria control programs in countries such as Iran.

Notes:
An insect is an organism having three pairs of jointed legs. Insects are small, land-dwelling arthropods. It has three distinct body sections : the head, thorax and abdomen. It has one pair of antennae (comprising the scapele, pedicel and flagellum), compound eyes and often one or two pairs of wings.

Notes:
The scientific name of peacock is Pavo Cristatus. It is also known as the Indian blue peafowl, common peafowl, blue peafowl, and blue Indian peafowl. It is a large and brightly coloured bird, is a species of peafowl native to the Indian subcontinent, but introduced in many other parts of the world.

Notes:
Oxygen liberated during photosynthesis comes from the splitting or hydrolysis of water in the green plants. Cornelius van Niel experimentally proved for the first time that the oxygen liberated during photosynthesis comes from water and not from carbon dioxide. Oxygen is expelled out of plants and Hydrogen is used to reduce Carbon dioxide to produce carbohydrates.

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Potatoes are examples of tubers : the swollen ends of stolons that may store starch. It is a stem because it has many nodes called eyes with spaces between eyes known as internodes. Potato tubers develop at the end of swollen underground stem structures, rhizomes.

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Dengue virus is the cause of dengue fever. Dengue virus is transmitted by female mosquitoes mainly of the species Aedes aegypti and, to a lesser extent, Ae. albopictus. This mosquito also transmits chikungunya, yellow fever and Zika infection. Dengue is widespread throughout the tropics, with local variations in risk influenced by rainfall, temperature and unplanned rapid urbanization.

Notes:
Insect and bird wings are analogous structures but not homologous structures. They are externally similar in appearance and function (i.e. for flying), but have dissimilar origin and developmental plan.

Notes:
The arteries (red) carry oxygen and nutrients away from your heart, to your body’s tissues. The veins (blue) take oxygen-poor blood back to theheart. Arteries begin with the aorta, the large artery leaving the heart. They carry oxygen-rich blood away from the heart to all of the body’s tissues.