The evolution of the seed is a very important step of evolution in land plants. The evolution of the seed enable plants to grow away from the very moist environments. That is why gymnosperms soon became the dominant plants. Gymnosperms and angiosperms both have ovule whcih is after fertilization becomes seed. The ovule in the gymnosperm is naked and not enclosed in the fruit, whereas in the angiosperms seeds are enclosed in the fruits.
Blue and yellow are co-dominant traits and none of these traits are expressed individually in the off springs. Green color is produced after the combination of yellow and blue trait.