General Science Questions (MCQs) for Competitive Examinations

Notes:
‘Survival of the fittest’ is a phrase that originated from Darwinian evolutionary theory as a way of describing the mechanism of natural selection. Herbert Spencer first used the phrase, after reading Charles Darwin’s On the Origin of Species, in his Principles of Biology (1864), in which he drew parallels between his own economic theories and Dar-win’s biological ones.

Notes:
Bonsai is the art of aesthetic miniaturization of trees and plants in containers. A bonsai plant is not a dwarf plant but equal to the full sized flowering plant. The main objective of bonsai plants is to create a tree or plant, and even landscapes, in miniature at household level.

Notes:
Although beaks vary significantly in size and shape from species to species, their underlying structures have a similar pattern. All beaks without teeth are composed of two jaws, generally known as the upper mandible (or maxilla) and lower mandible (or mandible).

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The platypus, also known as the duck-billed platypus, is a semi-aquatic egg-laying mammal endemic to eastern Australia. It is one of the five extant species of monotremes, the only mammals that lay eggs instead of giving birth.

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Femur (thigh bone) is the longest bone in the human body. It is the upper bone of the leg or hind leg. The head forms a ball-and-socket joint with the hip, being held in place by a ligament within the socket and by strong surrounding ligaments. By most measures the femur is the strongest bone in the body.

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:
All acids contain hydrogen atom (s). In aqueons state, they produce hydrogen ions. Dilute acids react with some metals that are more electro positive than hydrogen such as Sodium, Potassium, Calcium, iron, etc to form salts. Sodium replaces two hydrogen atoms from Sulfuric acid (H2SO4) to form a normal salt, Sodium Sulphate (Na2SO4). If only one atom of hydrogen is replaced by sodium, it forms an acid salt, Sodium Hydrogen Sulphate (NaHSO4).

Notes:
The atmosphere of the Earth is an envelope of gases extending to a height of 200km. It includes troposphere, slratosphere, inonosphere and thermosphere.

Notes:
Nylon is a generic designation for a family of synthetic polymers, more specifically aliphatic or semi-aromatic polyamides. They can be melt-processed into fibers, films or shapes. Nylon polymers have found significant commercial applications in fibers, in shapes and in films.