What is actually a chromosome and gene ?How does a sperm in male travel to ova inside the female body ?(how does it fuse)

A structure is found inside the nucleus of a cell.A chromosome is made up of proteins and DNA organized into genes. Each cell normally contains 23 pairs of chromosomes.

The basic unit of heredity occupies a specific location on a chromosome. Each consists of nucleotides arranged in a linear manner. Most genes code for a specific protein or segment of protein leading to a particular characteristic or function.