Fungal reproduction is complex and about a third of all fungi reproduce using more than one method of propagation. Majority of fungi produce spores that are haploid cells that can undergo mitosis to form multicellular haploid individuals. They can reproduce asexually by fragmentation, budding or producing spores, or sexually with homothallic or heterothallic mycelia.
Asexual reproduction occurs through vegetative spores called as conidia. Fragmentation and budding off of the mycelia also leads to their developing into separate individuals. These methods maintain clonal population and allow more rapid dispersal than sexual reproduction. All fungal phyla except Glomeromycota display sexual reproduction with meiosis. Compatible individuals may combine by fusing their hyphae together into an interconnected network.
This process is called as anastomoses and is required for the initiation of the sexual cycle. Some species may allow mating only between individuals of opposite mating types, whereas others can mate and sexually reproduce with any other individual or itself. For terrestrial fungi, the mycelium grows underground and can extend for miles.
In many fungi, the hyphae play an important role in the reproductive stage of the organism. For example, some fungi produce a fruiting body formed from hyphae that stick up out of the ground. During asexual reproduction, some hyphae become spore-producing bodies called sporangia or conidia. Sporangia can be unicellular or multicellular, and look like a sac or a capsule. Once the spores land on a suitable habitat, they germinate a new hypha that grows into a mycelium. Once the spores disperse, they will germinate and form a new mycelium.
The phylum Ascomycota includes fungi such as the one responsible for athlete's foot; the phylum Basidiomycota includes fungi such as mushrooms. Some types of fungi that reproduce asexually can also reproduce sexually, according to the National Center for Biotechnology Information. Within the gametangia, the nuclei from the cells of the two individuals fuse. Karyogamy produces a spore that has double the normal number of chromosomes, and sexual reproduction of fungi results in the production of two mating types rather than two sexes.
During meiosis, which follows karyogamy, this diploid spore halves itself to create two spores each with the normal number of chromosomes. Fungi can reproduce asexually by fragmentation, budding, or producing spores, or sexually with homothallic or heterothallic mycelia. Perfect fungi reproduce both sexually and asexually, while imperfect fungi reproduce only asexually by mitosis.
In both sexual and asexual reproduction, fungi produce spores that disperse from the parent organism by either floating on the wind or hitching a ride on an animal. Fungal spores are smaller and lighter than plant seeds. The giant puffball mushroom bursts open and releases trillions of spores. The huge number of spores released increases the likelihood of landing in an environment that will support growth. Fungi reproduce asexually by fragmentation, budding, or producing spores.
Fragments of hyphae can grow new colonies. Mycelial fragmentation occurs when a fungal mycelium separates into pieces with each component growing into a separate mycelium. Somatic cells in yeast form buds. During budding a type of cytokinesis , a bulge forms on the side of the cell, the nucleus divides mitotically, and the bud ultimately detaches itself from the mother cell.
The most common mode of asexual reproduction is through the formation of asexual spores, which are produced by one parent only through mitosis and are genetically identical to that parent. Spores allow fungi to expand their distribution and colonize new environments. They may be released from the parent thallus, either outside or within a special reproductive sac called a sporangium. There are many types of asexual spores.
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