Health

What is the health impact of wildfire smoke?

California, home of the freeway and the car-based lifestyle, has long struggled with air pollution—and been a pioneer in cleaning up the air, for example in vehicle emission standards. But in recent years, a new threat ...

Health

Climate change lengthening allergy season

Air levels of pollen and mold spores in the San Francisco Bay Area are elevated for about two more months per year than in past decades, and higher temperatures are to blame, a Stanford Medicine study has found.

Diseases, Conditions, Syndromes

Automating ringworm diagnosis

Ringworm, known more correctly as dermatophytosis, is a skin infection caused by any of forty or so different types of microbial fungus. It causes inflammation and itchiness, making the skin scaly and forming a circular rash, ...

Immunology

Q&A: What patients should know about fall and winter allergies

As we transition into colder months, fall and winter allergy sufferers may notice a change in their quality of life. If you're wondering whether or not you or your child have fall or winter allergies, here are some signs ...

Diseases, Conditions, Syndromes

Researchers create air filter that can kill the coronavirus

Researchers from the University of Houston, in collaboration with others, have designed a "catch and kill" air filter that can trap the virus responsible for COVID-19, killing it instantly.

Diseases, Conditions, Syndromes

Why does the CDC want us to 'Think Fungus'?

When people think of infectious microbes, they typically think of bacteria and virus. There is, however, another enormous group of organisms that can affect our health: fungi.

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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.

This text uses material from Wikipedia, licensed under CC BY-SA