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.
The closest that the Earth and Mars would ever be is a distance of 33.9million miles â that's 9,800 times the distance between London and New York. That's really rare though: the more useful distance is the average, which is 140million miles.