Artificial insemination is a method used in animal husbandry to genetically upgrade stock by producing good quality off springs. In humans, the process is used to induce pregnancy in case of reproductive blocks.
Sperm from a donor of high genetic quality is collected, tested and counted under the microscope. The samples are stored in fine glass tubes and frozen in liquid nitrogen. This makes it possible for samples to be sent all over the world without the donor having to leave the area. During the actual process of artificial insemination, sperm samples are introduced into the opening of the wombs by means of a syringe to which a long tube is attached. Entire herds may be impregnated at a time using samples from a donor of high quality. In humans, the process is used if there is a blockage in the mouth of the womb. In this case the sperm is directly introduced into the womb itself.
IQ, or intelligence quotient, is commonly used as a measure of an individual’s level of intelligence. Right from early childhood an individual’s level of intelligence grows with age. A normal child of a certain age is taken to have a certain level of intelligence which can be measured by a set of carefully designed tests, such as identifying objects, answering simple objective tests and solving simple arithmetical or logic problems. If the performance of the child matches with that expected from an average child of the same age; that is, if his age in years is the same as his mental age, the , child has an IQ of 100. If the performance is below average, it is less than 100, and if above average it is more than 100. The IQ is calculated by dividing the mental age by the actual age in years and multiplying the ratio by 100.
From the moment they leave the launch pad, unmanned spacecrafts are controlled by coded radio signals. The two-way communication is maintained with the help of large dish antennas located at earth stations. Two kinds of signals are used. Instruments on board the spacecraft continuously monitor the health of the various systems such as cameras, antenna, and batteries. These also check its orientation and flight path and send back telemetry signals to ground stations. These signals tell the scientists if the spacecraft is behaving the way it is designed to. If any change in the path or orientation is necessary to keep the spacecraft on course, command signals are sent which operate tiny gas jets on board to turn the spacecraft in any desired direction. Pictures and other data collected by on-board instruments are also transmitted back to earth via radio signals.
Unlike a motor vehicle on road, a train moves on a pair of rails and its movement is controlled by the way the rails or tracks are linked. The linking or delinking of tracks is done from the control cabin using special segments of tracks called ‘points’.
