Cross over is a process during meiosis where two chromosomes pair up and exchange segments of their genetic material.
Recombination refers to any process in which DNA sequences interact and undergo a physical rearrangement.
Genetic variation refers to diversity in gene frequencies, which can lead to variations among individuals within species due to crossing over.
Meiosis is a type of cell division that reduces the number of chromosomes by half, creating four haploid cells, each genetically distinct from the parent cell that gave rise to them.