Why does green replace yellow in the primary colors?

[SerraYX]

Ok, I've always wondered this, plus I need to know for a upcoming presentation.

When dealing with adjustable degrees of the three primary colors, like in computer palettes and TV controls, why is yellow replaced with green when blending colors?

 

[Basilisk6]

Red, green, and blue correspond to the 3 types of cones in the human eye, each of which is especially sensitive to a particular one of these 3 colors. Just look on google for a number of sites, like this one. There's plenty of info out there.