General Science Questions (MCQs) for Competitive Examinations

Notes:
The loose union of structure of the same whorl is called cohesion, but the intimate histological union is called connation. When anthers are fused with each other, the condition is described as syngenesious e.g., Compositae, Lobeliaceae. This fusion is called cohesion. When there is fusion of stamens with petals, they are described as epipetalous e.g., Gamopetale.

Notes:
DOTS (Directly Observed Treatment, Short Course), also known as TB-DOTS, is the name given to the tuberculosis control strategy recommended by the World Health Organization. It is the best curative method for treatment of tuberculosis being highly efficient and cost-effective strategy.

Notes:
The bamboo actually belongs to the grass family and is actually the tallest grass of all. There are kinds of bamboo which are said to grow as tall as 100 feet in height. The thickest bamboo can be 0.2m – 0.3m (8-12″) thick. Bamboo is a perennial grass with woody stems that are divided into sections by joints called nodes. One of the fastest-growing plants on the planet. However, they are known to die after flowering.

Notes:
A vector-borne disease is one in which the pathogenic microorganism is transmitted from an infected individual to healthy individual by an arthropod or other agent, sometimes with other animals serving as intermediary hosts. The transmission depends upon the attributes and requirements of at least three different living organisms: the pathogenic agent, either a virus, protozoa, bacteria, or helminth (worm); the vector, which are commonly arthropods such as ticks or mosquitoes; and the human host.

Notes:
Pneumatophores are spongy erect roots extending above the surface of the water that facilitate the exchange of oxygen and carbon dioxide for the roots. They are specialized root structures that grow out from the water surface where inadequate oxygen required for normal respiration of the roots is present. They are seen in many mangrove species.

Notes:
The cerebrum in fore brain is the seat of intelligence and provides us with the ability to read, write and speak; make calculations and compose music; remember the past and plan for the future; and create works. However, hypothalamus acts as centre for the emotional reactions regulating feeling of thirst, hunger, sexual desire, etc.

Notes:
In botany, heliophytes refer to plants that thrive in bright sunlight; while those growing best in shade are known as sciophytes. Heliophytes are capable of a more efficient use of high light intensities than sciophytes. Examples of heliophytes are sugar cane, sunflower and maize.

Notes:
A mixture of water and alcohol is separated by the process of distillation because they hve a difference of more than 25°C in their boiling points. At 78°C, alcohol starts to vaporize. The vapours are condensed in the condenser and alcohol is collected in the receiver leaving water in distillant in flask.

Notes:
Nitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The transformation of ammonia to nitrite than into nitrate is usually the rate limiting step of nitrification.Nitrification is an important step in the nitrogen cycle in soil.

• 2NO2(-) + O2 —Nitrification> 2NO3(-)

Notes:
Among the given options, mercury has the lowest melting point of -38.83 °C. in fact, Mercury has the lowest melting point among all metals and is the only metal that exists as liquid at room temperature. The melting point of Carbon, Silver and Gold is 3550 °C, 961.78 °C and 1064.18 °C respectively.