Chiasma. The cross-shaped exchange configuration between non sister chromatids of homologous chromosomes that is visible during prophase I of meiosis. chiasma The site where the exchange of chromosome segments between homologous chromosomes takes place (crossing-over) (pl.: chiasmata). PICTURE
Vegan diets are based on grains and other seeds, legumes (particularly beans), fruits, vegetables, edible mushrooms, and nuts. Meat analogues (mock meats) based on soybeans (tofu), or wheat-based seitan/gluten, are a common source of plant protein, usually in the form of vegetarian sausage, mince, and veggie burgers.
Vegans follow a strict vegetarian diet, which means that all animal products are out. Besides meat, this includes items such as milk, yogurt, butter and eggs. There are several vegan-friendly substitutes for yogurt. Some of these alternatives still contain the same active bacterial cultures as dairy-based yogurts, making them beneficial for digestion.