Specifically, a portion of a chromosome is broken and reattached on another chromosome. Recombination is also referred to as crossing-over . This condition most often afflicts males. One DNA molecule becomes two identical ones. This is accomplished by the DNA molecule unwinding and unzipping along its base pairs so that both sides can be copied by free nucleotides .
Replication is triggered by an enzyme .
Ribosomes are the sites where proteins are assembled. Each ribosome is composed of 3 RNA strands and 54 proteins woven into 2 separate, but entangled lumps. Unlike DNA , RNA is single stranded. Sex cells are produced by the meiosis process. See somatic cell .