Bud propagation: The most common asexual propagation mode of yeast is bud propagation. Buds occur at predetermined points on the cell wall, which are called bud marks. Each yeast cell has one or more bud marks. Mature yeast cells sprout buds, and the nucleus of the mother cell splits into two sub-nuclei, one of which enters the bud with the cytoplasm of the mother cell, and when the bud approaches the size of the mother cell, it falls off from the mother cell and becomes a new individual, and so on. If the yeast grows vigorously, new buds can grow on the buds before they fall off from the mother cells, and finally form pseudohyphae.
When the nutritional status is not good, some yeasts that can reproduce sexually will form spores (generally four) and germinate when the conditions are suitable.