Psychology Glossary. Genotype. The total set of genes contained within an organisms cells. Organisms contain some genes that are expressed (you can consider the expressed to mean that the gene is active or being used) and some that are not. Regardless, all the genes an organism has are considered the genotype.
Mars' closest approach to the Earth is called opposition, and occurs roughly every 780 days.
This, by the way, is called a Hohman Transfer Orbit, and is the mainstay of interplanetary space travel. It depends on the details of the orbit you take between the Earth and Mars. The typical time during Mars's closest approach to the Earth every 1.6 years is about 260 days. Again, the details depend on the rocket velocity and the closeness of the planets, but 260 days is the number I hear most often give or take 10 days.