Question

what is gene explain me briefly plz

Answer 1

A gene is a sequence of DNA or RNA which codes for a molecule that has a function. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. 
hope it helps u ✌

Answer 2

a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
"playing tennis is in my genes"