Question

example of constititive gene

Answer 1

For example there are defense related genes in your body, their expression is highly increased when you are infected with bacteria

Answer 2

@ssmishra

Answer 3

the gene that is constantly transcribed irrespective of change in environment

Answer 4

As Jayanthjeeva says genes can vary in their level of transcription (how much protein is produced at a given time from that gene) according to changes in environment, such as mayankdevnani's example, where genes are expressed at higher rates in cells of the immune system in response to infection with foreign pathogens. Constitutive genes are genes that are required at a constant level at all times, such as the "housekeeping" genes that maintain the cells integrity, such as the Na+/K+-ATPase, which is a protein that is vital for keeping the cell intact, whether an attack from foreign substances is present or not.