Fungi are eukaryotic and saprophytic microorganisms that grow on dead and decaying matter. These organisms release digestive enzymes that break down leaves, fruit and other organic material into simple molecules. These can grow on wood, clothes, food, fruits, leather shoes, etc by breaking down complex organic matter into simpler forms with the help of extracellular digestive enzymes such as cellulases, proteases, phosphatases, etc.
Genetic variation happens when one organism in the population mates with a genetically different organism. Same species, different genetics such as color or height/weight.
According to ChaCha.com, "Parthenogenesis is a form of agamogenesis in which an unfertilized egg develops into a new individual. Parthenogenesis occurs naturally in many plants and invertebrates. This differs from other forms of asexual reproduction because an egg is used."
Non-disjunction occurs when a the chromosomes do not split properly during meiosis resulting in too few chromosomes I believe.
