However, for those who do have food allergies, this distinction is very important. Food allergies can cause death. Food Allergens and Allergic Reactions. Like most allergic reactions, allergens in food are responsible for the food allergies. They are mostly proteins that resist the heat of cooking, stomach acids, and digestive enzymes.
In bryophytes (mosses and liverworts), the dominant generation is haploid, so that the gametophyte comprises what we think of as the main plant. The opposite is true for tracheophytes (vascular plants), in which the diploid generation is dominant and the sporophyte comprises the main plant. Bryophyte Generations
A gametophyte is the haploid multicellular stage in the alternation of generations life cycle of plants and algae. It develops from a spore by mitotic cell division. Spores are the products of meiosis in sporophytes.Gametophytes produce haploid gametes by mitosis. In some types of plants and algae (e.g. Ulva) gametes are isogamous --that is, the gametes are all of one size, shape and general morphology.In land plants, Anisogamy is universal. As in animals, female and male gametes are called, respectively, eggs and sperm.The fusion of male and female gametes produces a diploid zygote, which develops by repeated mitotic cell divisions into a multicellular sporophyte.n addition, these exosporic gametophytes are normally bisexual (produce both sperm and eggs). In heterosporous vascular plants (plants that produce both microspores and megaspores), the gametophyte develops endosporicallyâwithin the spore wall.