Sexual spore called Zygospore is formed by the fusion of two similar cells. Asexual reproduction occurs by sporangiospore Hypahe are generally aseptate. No sexual stage is present. Asexual reproduction occurs by means of conidia. They are pathogenic to most of the human beings and animals.

Author:Dirg Monris
Language:English (Spanish)
Published (Last):18 February 2017
PDF File Size:10.25 Mb
ePub File Size:13.8 Mb
Price:Free* [*Free Regsitration Required]

Hyphae grow at their tips apices ; new hyphae are typically formed by emergence of new tips along existing hyphae by a process called branching, or occasionally growing hyphal tips fork, giving rise to two parallel-growing hyphae. These growth processes lead to the development of a mycelium , an interconnected network of hyphae.

Septate hyphae are divided into compartments separated by cross walls internal cell walls, called septa, that are formed at right angles to the cell wall giving the hypha its shape , with each compartment containing one or more nuclei; coenocytic hyphae are not compartmentalized.

Mycelia grown on solid agar media in laboratory petri dishes are usually referred to as colonies. These colonies can exhibit growth shapes and colors due to spores or pigmentation that can be used as diagnostic features in the identification of species or groups. Growth and physiology Mold growth covering a decaying peach. The frames were taken approximately 12 hours apart over a period of six days.

The growth of fungi as hyphae on or in solid substrates or as single cells in aquatic environments is adapted for the efficient extraction of nutrients, because these growth forms have high surface area to volume ratios. Fungi have evolved a high degree of metabolic versatility that allows them to use a diverse range of organic substrates for growth, including simple compounds such as nitrate , ammonia , acetate , or ethanol.

This form of "radiotrophic" growth has been described for only a few species, the effects on growth rates are small, and the underlying biophysical and biochemical processes are not well known. These structures aid reproduction by efficiently dispersing spores or spore-containing propagules. Asexual reproduction Asexual reproduction occurs via vegetative spores conidia or through mycelial fragmentation. Mycelial fragmentation occurs when a fungal mycelium separates into pieces, and each component grows into a separate mycelium.

Mycelial fragmentation and vegetative spores maintain clonal populations adapted to a specific niche , and allow more rapid dispersal than sexual reproduction. Sexual reproduction See also: Mating in fungi and Sexual selection in fungi Sexual reproduction with meiosis has been directly observed in all fungal phyla except Glomeromycota [81] genetic analysis suggests meiosis in Glomeromycota as well.

It differs in many aspects from sexual reproduction in animals or plants. Differences also exist between fungal groups and can be used to discriminate species by morphological differences in sexual structures and reproductive strategies. Fungi employ two mating systems : heterothallic species allow mating only between individuals of opposite mating type , whereas homothallic species can mate, and sexually reproduce, with any other individual or itself.

In sexually reproducing fungi, compatible individuals may combine by fusing their hyphae together into an interconnected network; this process, anastomosis , is required for the initiation of the sexual cycle. Many ascomycetes and basidiomycetes go through a dikaryotic stage, in which the nuclei inherited from the two parents do not combine immediately after cell fusion, but remain separate in the hyphal cells see heterokaryosis.

During cell division , formation of the hook ensures proper distribution of the newly divided nuclei into the apical and basal hyphal compartments. An ascus plural asci is then formed, in which karyogamy nuclear fusion occurs.

Asci are embedded in an ascocarp , or fruiting body. Karyogamy in the asci is followed immediately by meiosis and the production of ascospores. After dispersal, the ascospores may germinate and form a new haploid mycelium. Compatible haploid hyphae fuse to produce a dikaryotic mycelium. However, the dikaryotic phase is more extensive in the basidiomycetes, often also present in the vegetatively growing mycelium.

A specialized anatomical structure, called a clamp connection , is formed at each hyphal septum. As with the structurally similar hook in the ascomycetes, the clamp connection in the basidiomycetes is required for controlled transfer of nuclei during cell division, to maintain the dikaryotic stage with two genetically different nuclei in each hyphal compartment. In fungi formerly classified as Zygomycota , haploid hyphae of two individuals fuse, forming a gametangium , a specialized cell structure that becomes a fertile gamete -producing cell.

The gametangium develops into a zygospore , a thick-walled spore formed by the union of gametes. When the zygospore germinates, it undergoes meiosis , generating new haploid hyphae, which may then form asexual sporangiospores. These sporangiospores allow the fungus to rapidly disperse and germinate into new genetically identical haploid fungal mycelia. This ejection ensures exit of the spores from the reproductive structures as well as traveling through the air over long distances.

The hydnoid fungi tooth fungi produce spores on pendant, tooth-like or spine-like projections. Most of the researched species of fungus are transported by wind.

Homothallic fungi include species with an aspergillus-like asexual stage anamorphs occurring in numerous different genera, [99] several species of the ascomycete genus Cochliobolus , [] and the ascomycete Pneumocystis jiroveccii.

Other sexual processes Besides regular sexual reproduction with meiosis, certain fungi, such as those in the genera Penicillium and Aspergillus , may exchange genetic material via parasexual processes, initiated by anastomosis between hyphae and plasmogamy of fungal cells. It is known to play a role in intraspecific hybridization [] and is likely required for hybridization between species, which has been associated with major events in fungal evolution. In contrast to plants and animals , the early fossil record of the fungi is meager.

Factors that likely contribute to the under-representation of fungal species among fossils include the nature of fungal fruiting bodies , which are soft, fleshy, and easily degradable tissues and the microscopic dimensions of most fungal structures, which therefore are not readily evident. Fungal fossils are difficult to distinguish from those of other microbes, and are most easily identified when they resemble extant fungi.

Fungal fossils do not become common and uncontroversial until the early Devonian —


Kingdom Mycota or Fungi: General characteristics and classification

Hifa tumbuh di ujungnya apeks ; hifa baru biasanya dibentuk oleh munculnya ujung baru di sepanjang hifa yang ada dengan proses yang disebut percabangan, atau kadang-kadang pada ujung hifa tumbuh percabangan menjadi dua, sehingga menimbulkan dua hifa yang tumbuh paralel. Proses pertumbuhan ini mengarah pada perkembangan miselium , jaringan hifa yang saling terhubung. Hifa septat dibagi menjadi ruang-ruang yang dipisahkan oleh dinding silang dinding sel internal, yang disebut septa, yang terbentuk tegak lurus terhadap dinding sel yang memberikan bentuk hifa , dengan masing-masing ruang berisi satu atau lebih inti; hifa senositik tidak terbagi menjadi ruang-ruang. Miselia yang ditumbuhkan pada media agar padat di cawan petri laboratorium biasanya disebut sebagai koloni. Koloni-koloni ini dapat menunjukkan bentuk pertumbuhan dan warna karena spora atau pigmentasi yang dapat digunakan sebagai fitur diagnostik dalam identifikasi spesies atau kelompok. Pertumbuhan dan fisiologi[ sunting sunting sumber ] Pertumbuhan kapang menutupi sebuah persik yang membusuk.


Kingdom Fungi

February 1, Klasifikasi makhluk hidup merupakan kegiatan yang dilakukan untuk mengelompokkan makhluk hidup. Pengelompokan tersebut didasarkan pada kesamaan ciri maupun perbedaan yang ditemukan pada setiap makhluk hidup. Klasifikasi makhluk hidup dilakukan dengan melihat ciri ciri makhluk hidup yang paling umum hingga yang paling spesifik pada makhluk hidup. Selain pengelompokan dari ciri-ciri makhluk hidup, pengelompokan juga dilakukan dengan dasar ukuran, manfaat, dan juga habitat makhluk hidup. Klasifikasi makhluk hidup dipelajari dalam ilmu taksonomi. Olehnya, kelompok makhluk hidup diklasifikasikan menjadi dua kelompok, yakni animalia hewan dan juga vegetabilia tumbuhan. Berikut ini aturan yang digunakan untuk pemberian nama ilmiah pada makhluk hidup: Nama ilmiah menggunakan bahasa Latin.

Related Articles