what is fungi? explain it .
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Answer:
Fungi Definition
Fungi (singular: fungus) are a kingdom of usually multicellular eukaryotic organisms that are heterotrophs (cannot make their own food) and have important roles in nutrient cycling in an ecosystem. Fungi reproduce both sexually and asexually, and they also have symbiotic associations with plants and bacteria. However, they are also responsible for some diseases in plants and animals. The study of fungi is known as mycology.
Fungi Characteristics
Some fungi are single-celled, while others are multicellular. Single-celled fungi are called yeast. Some fungi alternate between single-celled yeast and multicellular forms depending on what stage of the life cycle they are in. Fungi cells have a nucleus and organelles, like plant and animal cells do. The cell walls of fungi contain chitin, which is a hard substance also found in the exoskeletons of insects and arthropods such as crustaceans. They do not contain cellulose, which commonly makes up plant cell walls.
Multicellular fungi have many hyphae (singular: hypha), which are branching filaments. Hyphae have a tubular shape and are split into cell-like compartments by walls that are known as septa. These cells can have more than one nucleus, and nuclei and other organelles can move in between them. (There is some debate over whether multicellular fungi are truly multicellular, because organelles and cytoplasm can move from one cell to the other in a process called cytoplasmic streaming. They are commonly known as multicellular, but they are not multicellular in the same way as plants and animals, which have enclosed cells.) A fungus’s network of hyphae is called a mycelium.
Penicillium
These are hyphae of a Penicillium fungus.
Fungi are heterotrophs; they cannot make their own food and must obtain nutrients from organic material. To do so, they use their hyphae, which elongate and branch off rapidly, allowing the mycelium of the fungus to quickly increase in size. Some fungi hyphae even form root-like threads called rhizomorphs, which help tether the fungus to the substrate that it grows on while allowing it to quickly obtain more nutrients from other sources. Fungi are opportunists, which means that they can obtain nutrients from a wide variety of sources and thrive in a wide range of environmental conditions. Some fungi obtain nutrients from dead organic matter; these fungi are called saprobes and are decomposers, which break down and get rid of dead organisms. Other fungi parasitize plants and are responsible for plant diseases like Dutch elm disease. However, fungi can also have symbiotic (mutually beneficial) relationships with photosynthetic algae or bacteria, and with plant roots. A symbiotic association of a fungus and an animal that photosynthesizes is called a lichen, while a plant root-and-fungus association is called a mycorrhiza.
Fungi Reproduction
Most fungi can reproduce through both sexual and asexual reproduction. Asexual reproduction occurs through the release of spores or through mycelial fragmentation, which is when the mycelium separates into multiple pieces that grow separately. In sexual reproduction, separate individuals fuse their hyphae together. The exact life cycle depends on the species, but generally multicellular fungi have a haploid stage (where they have one set of chromosomes), a diploid stage, and a dikaryotic stage where they have two sets of chromosomes but the sets remain separate.
Explanation:
a building is made up of brick. so, a brick is the unit of construction . similarly,all living things are made up put a tiny cells . cell is the structural and functional unit of all living things . some plants and animals consist of single cell. they are called unicellular organisms . some examples are bacteria like fungi are some examples of unicellular organisms are extremely small and not visible to the naked eyes. they are onl seen by with the help of microscope .