Answer
A lack of mitosis between meiosis and fertilization would mean that such a lineage of plants would be more like animals, going from diploid stage to haploid gametophytes and right back to a diploid zygote. This would eliminate the gametophyte and the possibility of having nutritive tissue in the seed, making the life cycle much more like that of an animal. If a seed was present, any nutritive material would have to be produced more like the yolk of an animal egg. This would be a radical change in the plant life cycle, and many flower parts might reduce in size due to these changes, since fewer cells would be involved in their structure.
Work Step by Step
Here you could go back in the book and review the comparison among plant, animal, and fungal lifecycle. This will show you that the life cycle described is more like that of animals. Look at the reproductive adaptations of plants and see which would need to be modified under these new circumstances.