Questions

Gene is a hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome and determines a particular characteristic in an organism.

In short it is a piece or segment of chromosome.

Genes undergo mutation when their DNA sequence changes. 

Digboi, in Assam is where the oldest oil refinery in India. It was build in 1901.

Ctrl+Shift+F Opens the Font dialog box with the focus at the Font combo box.

An operating system is a program that acts as an intermediary between the user and the computer hardware. The purpose of an OS is to provide a convenient environment in which user can execute programs in a convenient and efficient manner. It is a resource allocator responsible for allocating system resources and a control program which controls the operation of the computer hardware.

The brain has three main parts the cerebrum, cerebellum and brainstem. As cerebrum is the largest part of the brain it is divided into two hemispheres i.e, right and left. It performs many functions like vision, hearing, touch, learning, consciousness, emotions, etc...

Mahavira