When it is said that a gene is "turned off" this usually means that this particular gene is no longer making the directions that need to be followed in order to make proteins. Therefore the proteins that are needed for a specific job, such as tolerating lactose, are not being produced. So the answer in this question would be that the RNA for that gene is not translated into protein.
the length of a cobra doesn't help with the study of life. The moon doesn't either because there is no life on the moon. And how fast the earth rotates is more of a earth science question. I hope this somewhat helps
