Related topics: bacteria · fungus · pathogens

Fungal pathogen disables plant defense mechanism

Cabbage plants defend themselves against herbivores and pathogens by deploying a defensive mechanism called the mustard oil bomb: when the plant tissue is damaged, toxic isothiocyanates are formed and can effectively fend ...

New ancient plant captures snapshot of evolution

In a brilliant dance, a cornucopia of flowers, pinecones and acorns connected by wind, rain, insects and animals ensure the reproductive future of seed plants. But before plants achieved these elaborate specializations for ...

Fungus application thwarts major soybean pest, study finds

The soybean cyst nematode sucks the nutrients out of soybean roots, causing more than $1 billion in soybean yield losses in the U.S. each year. A new study finds that one type of fungi can cut the nematodes' reproductive ...

Can a tiny invasive snail help save Latin American coffee?

While conducting fieldwork in Puerto Rico's central mountainous region in 2016, University of Michigan ecologists noticed tiny trails of bright orange snail excrement on the undersurface of coffee leaves afflicted with coffee ...

Sanitary care by social ants shapes disease outcome

Sanitary care in ants to fight disease is known to improve the wellbeing of the colony, yet it has been unclear how social disease defense interferes with pathogen competition inside the individual host body. In their recent ...

Bark beetles control pathogenic fungi

Ants and honeybees share nests of hundreds or thousands of individuals in a very small space. Hence the risk is high that infectious diseases may spread rapidly. In order to reduce this risk, the animals have developed special ...

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Spore

In biology, a spore is a reproductive structure that is adapted for dispersal and surviving for extended periods of time in unfavorable conditions. Spores form part of the life cycles of many bacteria, plants, algae, fungi and some protozoans. A chief difference between spores and seeds as dispersal units is that spores have very little stored food resources compared with seeds.

Spores are usually haploid and unicellular and are produced by meiosis in the sporangium by the sporophyte. Once conditions are favorable, the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes.

Two gametes fuse to create a new sporophyte. This cycle is known as alternation of generations, but a better term is "biological life cycle", as there may be more than one phase and so it cannot be a direct alternation. Haploid spores produced by mitosis (known as mitospores) are used by many fungi for asexual reproduction.

Many ferns, especially those adapted to dry conditions, produce diploid spores. This form of asexual reproduction is called apogamy. It is a form of apomixis.

Spores are the units of asexual reproduction, because a single spore develops into a new organism. By contrast, gametes are the units of sexual reproduction, as two gametes need to fuse to create a new organism.

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