In a certain breed of plants, dark green is determined by the dominant gene 'G' and light green is determined by the recessive g
ene 'g'. The heterozygotes show 75% penetrance. If the parental cross GG x gg was made, how many of each of the expected phenotypes will be observed in a population of 400 F2 plants
When we cross GG and gg, 100% of the offspring will be heterozygous. If the heterozygotes show 75% penetrance meaning that there is a 75% probability that the plant that has the G gene will actually show it in it's phenotype.
So that means that 75% of the offspring should have dark green color, which means that 300 plants will have the expected phenotype and 100 will not.
The correct answer is fitness. The Theory of Evolution defines fitness as a result of the adaptations an organism has which increase its chance of survival.